CN104879115A - Method and device for determining underground measurement-while-drilling parameter - Google Patents

Abstract

The embodiment of the application provides a method and a device for determining underground measurement-while-drilling parameter. The method comprises the following steps: orderly determining drilling pillar nodes from a wellhead to a drill bit according to preset step length; obtaining wellbore inclination survey data of every measuring point, and calculating the well deviation change rate and the orientation change rate of the drilling pillar nodes between every two measuring points according to the wellbore inclination survey data; by referring to the well deviation change rate and the orientation change rate obtained through calculation, determining geological information of every drilling pillar node; determining inertia moment and linear buoyant weight of every drilling pillar node; obtaining the axial tension force of the wellhead drilling pillar and the torque of the wellhead drilling pillar; calculating the underground measurement-while-drilling parameter by using a preset drilling pillar tension torque differential equation and referring to geological information, inertia moment and linear buoyant weight of every drilling pillar node, and axial tension of the wellhead drilling pillar and the torque of the wellhead drilling pillar. By using the technical scheme provided by the embodiment of the application, the actual underground working condition can be exactly determined.

Description

A kind of downhole drill determination method for parameter and device

Technical field

The present invention relates to technical field of geophysical exploration, particularly relate to a kind of downhole drill determination method for parameter and device.

Background technology

In geophysical exploration process, the develop rapidly of information technology makes more in detail and more jumbo well data can be stored in sensor module memory, and enable a series of dynamic parameter be real-time transmitted at a high speed ground level control room or remote monitoring room, for driller and drilling engineer's Drilling optimization parameter, identify down-hole bottleneck factor, excavate drilling speed potentiality and improve overall drilling well performance reliable real time data support is provided.

At present, the domestic technology that shaft bottom dynamic pickup is grasped also do not have massive store and real time high-speed transmission dual-use function, and pipe nipple is high temperature resistant, high pressure limited in one's ability.In addition international larger hydrocarbon service company monopolizes the high-end measuring technique in down-hole and EQUIPMENT MARKET GUIDE, causes the expense of underground survey pipe nipple too high, and Domestic Oil And Gas Fields is faced with the double challenge of technology and cost in the analysis of down-hole information collect and transmit.Comprehensive logging instrument is of great significance for Drilling optimization tool with brill data collecting system as ground.The engineering parameter that earth's surface acquisition system provides and drilling fluid situation of change can be used for diagnosis and predictive engine is abnormal, but due to comprehensive logging system gather ground surface works data and downhole drill information difference very large, if only obtain the actual condition that these ground surface works data are just difficult to true reflection down-hole, and finally cause producing erroneous judgement to the differentiation of down-hole real working condition.

Summary of the invention

The object of the application is to provide a kind of downhole drill determination method for parameter and device, to determine the actual condition of down-hole accurately.

To achieve these goals, this application provides a kind of method of determination of downhole drill parameter, the method comprises:

Drill string node is determined from well head successively to drill bit direction according to default step-length;

Obtain the well deviational survey data of each measuring point, and according to the rate of deviation of drill string node between every two measuring points of described well deviational survey data calculating and the rate of azimuth change of drill string node;

In conjunction with the rate of deviation calculated and rate of azimuth change, determine the geological information of each drill string node;

Determine moment of inertia and the line buoyant weight of each drill string node;

Obtain the axial tension of well head drill string and the moment of torsion of well head drill string;

Utilize and preset the drill string tension and torque differential equation, in conjunction with axial tension and the well head drill string torque of the geological information of each drill string node, moment of inertia, line buoyant weight and well head drill string, determine downhole drill parameter.

In a preferred embodiment, described well deviational survey data comprise: hole angle, azimuth and well depth.

In a preferred embodiment, described geological information comprises: the rate of change of hole angle, azimuth, drill string curvature, drill string curvature variation, drill string curvature variation, drill string torsion and drill string torsion rate of change.

In a preferred embodiment, describedly determine that the moment of inertia of each drill string node and line buoyant weight comprise:

Obtain the drill string external diameter of described drill string Nodes and the drill string internal diameter of described drill string Nodes, and calculate the moment of inertia of drill string node according to described drill string external diameter and described drill string internal diameter;

Obtain the drilling fluid density of described drill string Nodes, the drill string steel density of described drill string Nodes and the aerial line weight of drill string of described drill string Nodes, and according to the line buoyant weight of described drilling fluid density, described drill string steel density and described drill string aerial line re-computation drill string node.

In a preferred embodiment, the axial tension of described acquisition well head drill string comprises:

Obtain the ground weight indicator reading in real drill-through journey, transmission efficiency that Hoisting System effectively restricts number and single pulley;

Effectively to restrict according to described ground weight indicator reading, Hoisting System the transmission efficiency determination weight on hook of number and single pulley, and using described weight on hook as well head drill string axial tension.

In a preferred embodiment, described downhole drill parameter comprises: drill bit axial tension and torque-on-bit.

In a preferred embodiment, described downhole drill parameter also comprises: drill bit axial tension, drill string friction drag.

In a preferred embodiment, the described default drill string tension and torque differential equation is as follows:

$\left\{\begin{array}{c}\frac{{\mathrm{dM}}_i}{\mathrm{dL}}=f_{1i}{r}_i{N}_i+m_i\\ \frac{{\mathrm{dT}}_i}{\mathrm{dL}}+{\mathrm{EIK}}_{\mathrm{bi}}\frac{{\mathrm{dK}}_{\mathrm{bi}}}{\mathrm{dL}}-f_{2i}{N}_i-C_i{V}_i-B_i+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{t}}_i=0\\ -E_i{I}_i\frac{d^2{K}_{\mathrm{bi}}}{{\mathrm{dL}}^2}+K_{\mathrm{bi}}{T}_i+E_i{I}_i{K}_{\mathrm{ni}}^2{K}_{\mathrm{bi}}+K_{\mathrm{bi}}{K}_{\mathrm{ni}}{M}_i+N_{\mathrm{ni}}+f_{1i}{N}_{\mathrm{bi}}+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{n}}_i=0\\ -\frac{d}{\mathrm{dL}}(E_i{I}_i{K}_{\mathrm{ni}}{K}_{\mathrm{bi}}+K_{\mathrm{bi}}{M}_i)-E_i{I}_i{K}_{\mathrm{ni}}\frac{{\mathrm{dK}}_{\mathrm{bi}}}{\mathrm{dL}}+N_{\mathrm{bi}}-f_{1i}{N}_{\mathrm{ni}}+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{b}}_i=0\end{array}\right.$

Wherein, $f_{1i}=\frac{2{\mathrm{\πr}}_i{\mathrm{\ω}}_i}{\sqrt{{V_i}^2+{\left(2{\mathrm{\πr}}_i{\mathrm{\ω}}_i\right)}^2}}f;$ $f_{2i}=\frac{V_i}{\sqrt{{V_i}^2+{\left({2\mathrm{\πr}}_i{\mathrm{\ω}}_i\right)}^2}}f;$ ${\stackrel{\→}{k}}_i\·{\stackrel{\→}{t}}_i=-\cos {\mathrm{\α}}_i;$ ${\stackrel{\→}{k}}_i\·{\stackrel{\→}{n}}_i=\frac{1}{K_{\mathrm{bi}}}\frac{d{\mathrm{\α}}_i}{\mathrm{dL}}\sin {\mathrm{\α}}_i;$ ${\stackrel{\→}{k}}_i\·{\stackrel{\→}{b}}_i=-\frac{1}{K_{\mathrm{bi}}}\frac{d{\mathrm{\φ}}_i}{\mathrm{dL}}{\sin }^2{\mathrm{\α}}_i;$ $N_i=\sqrt{N_{\mathrm{ni}}^2+N_{\mathrm{bi}}^2};$ $m_i=\frac{\mathrm{\π}\×{D_i}^3\×{\mathrm{\ω}}_i}{4}\×(\frac{{\mathrm{\τ}}_i}{\sqrt{({V_i}^2+{\left(D_i{\mathrm{\π\ω}}_i\right)}^2)}}+\frac{2\×{\mathrm{\μ}}_i}{D_{\mathrm{Wi}}-D_i});$ $B_i=\frac{D_i{\mathrm{\π\τ}}_i{V}_i}{\sqrt{{V_i}^2+{\left(D_i{\mathrm{\π\ω}}_i\right)}^2}};$

$C_i=\frac{{2\mathrm{\π\μ}}_i}{\ln \left(D_{\mathrm{wi}}\right)-\ln \left(D_i\right)}$

Wherein, M _irepresent the moment of torsion of i-th drill string Nodes, unit is Nm; T _irepresent the drill string axial tension of i-th drill string Nodes, unit is N; N _irepresent the normal pressure between i-th drill string Nodes drill string and the borehole wall, unit is N; N _birepresent N _iin subnormal durection component, unit is N; N _nirepresent N _iin principal normal durection component, unit is N; m _irepresent the external torque that mud produces, unit is Nm; f _1irepresent i-th drill string Nodes circumference friction factor; B _irepresent the axial force that i-th drill string Nodes mud shear force produces, unit is N; C _irepresent the axial force that i-th drill string Nodes mud viscosity produces, unit is N; f _2irepresent i-th drill string Nodes axial rub coefficient; g _irepresent the line buoyant weight of i-th drill string Nodes, unit is N/m; represent the component of i-th drill string Nodes line buoyant weight tangential direction, unit is N/m; represent the component in i-th drill string Nodes line buoyant weight principal normal direction, unit is N/m; represent the component in i-th drill string Nodes line buoyant weight binormal direction, unit is N/m; represent the rate of deviation of i-th drill string Nodes drill string; represent i-th drill string Nodes drill string rate of azimuth change; I _irepresent i-th drill string Nodes drill string moment of inertia, unit is m ⁴; K _birepresent i-th drill string Nodes drill string curvature, unit is 1/m; K _nirepresent i-th drill string Nodes drill string torsion, unit is 1/m; F represents frictional coefficient; V _ibe that i-th drill string Nodes pulls out of hole or speed uplink, unit is m/s; ω _irepresent i-th drill string Nodes drill string rotating speed, unit is 1/s; τ _irepresent i-th drill string Nodes drilling fluid yield value, unit is pa; μ _irepresent drilling fluid viscosity, unit is pas; E _irepresent the modulus of elasticity of i-th drill string Nodes drill string steel, unit is pa; L represents drill string length, and unit is m; α _irepresent i-th drill string Nodes drill string hole angle; D _wirepresent i-th drill string Nodes borehole diameter, unit is m; D _irepresent i-th drill string Nodes drill string external diameter, unit is m.

In a preferred embodiment, describedly determine that downhole drill parameter comprises:

According to the drill string torque increment of described default drill string tension and torque differential equation determination drill string Nodes, the drill string axial tension increment of drill string Nodes and the friction drag increment of drill string Nodes;

Determine the moment of torsion of each drill string node according to following formula, and using distance well head apart from the moment of torsion of maximum drill string node as torque-on-bit:

M _i＝M _i-1+ΔM _i

In above formula, M _irepresent the moment of torsion of i-th drill string Nodes; M _i-1represent the moment of torsion of the i-th-1 drill string Nodes; Δ M _irepresent the drill string torque increment of i-th drill string Nodes, wherein, the distance between i-th drill string node and well head is greater than the distance between the i-th-1 drill string node and well head;

Determine the axial tension of each drill string node according to following formula, and using distance well head apart from the axial tension of maximum drill string node as drill bit axial tension:

T _i＝T _i-1+ΔT _i

In above formula, T _irepresent the drill string axial tension of i-th drill string Nodes; T _i-1represent the drill string axial tension of the i-th-1 drill string Nodes; Δ T _irepresent the drill string axial tension increment of i-th drill string Nodes;

Friction drag according to following formula determination drill string::

F＝F ₁+F ₂+...+F _i-1+F _i

In above formula, F represents drill string friction drag; F _irepresent the friction drag of i-th drill string Nodes; F _i-1represent the friction drag of the i-th-1 drill string Nodes; Wherein, F _i=f _2in _i+ C _iv _i+ B _i.

The application also provides a kind of determining device of downhole drill parameter on the other hand, and this device comprises:

Drill string node determining unit, for successively determining drill string node from well head to drill bit direction according to presetting step-length;

Computing unit, for obtaining the well deviational survey data of each measuring point, and according to the rate of deviation of drill string node between every two measuring points of described well deviational survey data calculating and the rate of azimuth change of drill string node;

First data determination unit, for combining the rate of deviation and rate of azimuth change that calculate, determines the geological information of each drill string node;

Second data determination unit, for determining moment of inertia and the line buoyant weight of each drill string node;

Well head data capture unit, for the moment of torsion of the axial tension and well head drill string that obtain well head drill string;

Downhole drill parameter determination unit, for utilizing the default drill string tension and torque differential equation, in conjunction with axial tension and the well head drill string torque of the geological information of each drill string node, moment of inertia, line buoyant weight and well head drill string, determines downhole drill parameter.

From the embodiment of a kind of downhole drill determination method for parameter of above the application and device, the technical scheme that the embodiment of the present application provides by successively determining drill string node from well head to drill bit direction according to presetting step-length, and obtains the moment of torsion of the geological information of described drill string node, the moment of inertia of drill string node, the line buoyant weight of drill string node, the axial tension of well head drill string and well head drill string.Then utilize and preset the moment of torsion acquisition downhole drill parameter of the drill string tension and torque differential equation in conjunction with the line buoyant weight of the moment of inertia of the geological information of described drill string node, described drill string node, described drill string node, the axial tension of described well head drill string and described well head drill string.Described downhole drill parameter information and surface data are carried out organic combination, can realize more rationally, Drilling optimization operation more efficiently, real-time diagnosis underground working.

Accompanying drawing explanation

In order to be illustrated more clearly in the embodiment of the present application or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, the accompanying drawing that the following describes is only some embodiments recorded in the application, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.

Fig. 1 is the flow chart of the embodiment of a kind of downhole drill determination method for parameter of the application;

Fig. 2 is the schematic diagram of the determining device of a kind of downhole drill parameter that the embodiment of the present application provides.

Detailed description of the invention

Technical scheme in the application is understood better in order to make those skilled in the art person, below in conjunction with the accompanying drawing in the embodiment of the present application, technical scheme in the embodiment of the present application is clearly and completely described, obviously, described embodiment is only some embodiments of the present application, instead of whole embodiments.Based on the embodiment in the application, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all should belong to the scope of the application's protection.

The specific implementation of the embodiment of the present application is described below in detail with several concrete example.

Below the embodiment of a kind of downhole drill determination method for parameter of the application is first introduced.By reference to the accompanying drawings 1, this embodiment comprises:

S110: determine drill string node from well head successively to drill bit direction according to default step-length.

In certain embodiments, default step-length here can pre-set according to the drilling well situation of reality, can be generally 10m; Here drill string node is the node divided according to default step-length, and also namely when default step-length is 10m, every 10m arranges a drill string node.

S120: the well deviational survey data obtaining each measuring point, and according to the rate of deviation of drill string node between every two measuring points of described well deviational survey data calculating and the rate of azimuth change of drill string node.

In certain embodiments, the well deviational survey data of each measuring point in real drill-through journey can be obtained, and calculate the rate of deviation of the drill string node between two measuring points and the rate of azimuth change of drill string node according to described well deviational survey data.The interval of measuring point is here uncertain, surveys once for usual 10 to 30 meters, therefore, can have one or more drill string node between two measuring points in drilling process.Here well deviational survey data can comprise: the well depth of the hole angle of measuring point, the azimuth of measuring point and measuring point.The rate of deviation of drill string node between two measuring points and the rate of azimuth change of drill string node is calculated according to described well deviational survey data.Concrete, following design formulas can be utilized:

dα _i＝(α _j-α _j-1)/(L _j-L _j-1)

In above formula, d α _irepresent the rate of deviation of i-th drill string Nodes, i is drill string nodes, i=1,2 ..., i-1, i, α _jrepresent the hole angle at a jth measuring point place, j is measuring point number, j=1,2 ..., j-1, i, α _j-1represent the hole angle at jth-1 measuring point place; L _jrepresent the well depth at a jth measuring point place; L _j-1represent the well depth at jth-1 measuring point place;

dφ _i＝(φ _j-φ _j-1)/(L _j-L _j-1)

In above formula, d φ _irepresent the rate of azimuth change of i-th drill string Nodes; φ _jrepresent the azimuth at a jth measuring point place; φ _j-1represent the azimuth at jth-1 measuring point place; L _jrepresent the well depth at a jth measuring point place; L _j-1represent the well depth at jth-1 measuring point place.

In addition, need to further illustrate, first drill string node is also first measuring point.

S130: combine the rate of deviation and rate of azimuth change that calculate, determine the geological information of each drill string node.

In certain embodiments, after step S120 calculates the rate of deviation of drill string node and the rate of azimuth change of drill string node, in conjunction with the rate of deviation calculated and rate of azimuth change, the geological information of each drill string node can be determined.In certain embodiments, described geological information can comprise: the rate of change of hole angle, azimuth, drill string curvature, drill string curvature variation, drill string curvature variation, drill string torsion and drill string torsion rate of change.Concrete, the geological information of following design formulas determination drill string node can be utilized:

L _i＝h×(i-1)

In above formula, L _irepresent the well depth of i-th drill string Nodes, unit is m; Step-length is preset in h representative, and unit is m;

α _i＝α _j-1+dα _i×(L _i-L _j-1)

In above formula, α _irepresent the hole angle of i-th drill string Nodes; α _j-1represent the hole angle of jth-1 measuring point; D α _irepresent the rate of deviation of i-th drill string Nodes; L _irepresent the well depth of i-th drill string Nodes, unit is m; L _j-1represent the well depth of jth-1 measuring point, unit is m;

φ _i＝φ _j-1+dφ _i×(L _i-L _j-1)

In above formula, φ _irepresent the azimuth of i-th drill string Nodes; φ _j-1represent the azimuth of jth-1 measuring point; D φ _irepresent the rate of azimuth change of i-th drill string Nodes; L _irepresent the well depth of i-th drill string Nodes, unit is m; L _j-1represent the well depth of jth-1 measuring point, unit is m;

$K_{\mathrm{bi}}=\sqrt{(d{{\mathrm{\α}}_i}^2+\sin \left({\mathrm{\α}}_i\right)\×{{\mathrm{d\φ}}_i}^2)}$

In above formula, K _birepresent the drill string curvature of i-th drill string Nodes, unit is 1/m; D α _irepresent the rate of deviation of i-th drill string Nodes; α _irepresent the hole angle of i-th drill string Nodes; D φ _irepresent the rate of azimuth change of i-th drill string Nodes;

${\mathrm{dK}}_{\mathrm{bi}}=\frac{K_{\mathrm{bi}}-K_{\mathrm{bi}-1}}{h}$

In above formula, dK _birepresent the drill string curvature variation of i-th drill string Nodes; K _birepresent the drill string curvature of i-th drill string Nodes, unit is 1/m; K _bi-1represent the drill string curvature of the i-th-1 drill string Nodes, unit is 1/m; Step-length is preset in h representative, and unit is m;

${\mathrm{ddK}}_{\mathrm{bi}}=\frac{{\mathrm{dK}}_{\mathrm{bi}}-{\mathrm{dK}}_{\mathrm{bi}-1}}{h}$

In above formula, ddK _birepresent the rate of change of the drill string curvature variation of i-th drill string Nodes; DK _birepresent the drill string curvature variation of i-th drill string Nodes; DK _bi-1represent the drill string curvature variation of the i-th-1 drill string Nodes;

$K_{\mathrm{ni}}=d{\mathrm{\φ}}_i\×(1+\frac{{{\mathrm{d\α}}_i}^2}{{K_{\mathrm{bi}}}^2})\×\cos \left({\mathrm{\α}}_i\right)$

In above formula, K _nirepresent the drill string torsion of i-th drill string Nodes, unit is 1/m; K _birepresent the drill string curvature of i-th drill string Nodes, unit is 1/m; D α _irepresent the rate of deviation of i-th drill string Nodes; α _irepresent the hole angle of i-th drill string Nodes; D φ _irepresent the rate of azimuth change of i-th drill string Nodes;

${\mathrm{dK}}_{\mathrm{ni}}=\frac{K_{\mathrm{ni}}-K_{\mathrm{ni}-1}}{h}$

In above formula, dK _nirepresent the drill string torsion rate of change of i-th drill string Nodes; K _nirepresent the drill string torsion of i-th drill string Nodes, unit is 1/m; K _ni-1represent the drill string torsion of the i-th-1 drill string Nodes, unit is 1/m; Step-length is preset in h representative, and unit is m;

S140: moment of inertia and the line buoyant weight of determining each drill string node.

In certain embodiments, determine moment of inertia and the line buoyant weight of each drill string node, concrete, the drill string external diameter of described drill string Nodes and the drill string internal diameter of described drill string Nodes can be obtained, and calculate the moment of inertia of drill string node according to described drill string external diameter and described drill string internal diameter; Here drill string external diameter and drill string internal diameter can according to concrete drilling tool acquisition of informations.Specific formula for calculation is as follows:

$I_i=\frac{\mathrm{\π}}{64}({D_i}^4-{d_i}^4)$

In above formula, I _irepresent the moment of inertia of i-th drill string Nodes, unit is m ⁴; D _irepresent i-th drill string Nodes drill string external diameter, unit is m; d _irepresent the i-th drill string Nodes drill string internal diameter, unit is m;

Further, the drilling fluid density of described drill string Nodes, the drill string steel density of described drill string Nodes and the aerial line weight of drill string of described drill string Nodes can be obtained, and according to the line buoyant weight of described drilling fluid density, described drill string steel density and described drill string aerial line re-computation drill string node.Here drilling fluid density, drill string steel density and the aerial line of drill string are heavy can be obtained according to concrete drilling condition.Concrete design formulas is as follows:

$g_i=(1-\frac{{\mathrm{\ρ}}_{\mathrm{mui}}}{{\mathrm{\ρ}}_{\mathrm{casi}}})\×{\mathrm{pg}}_i$

In above formula, g _irepresent the line buoyant weight of i-th drill string Nodes; ρ _muirepresent drilling fluid density, unit is g/cm ³; ρ _casirepresent drill string steel density, unit is g/cm ³; Pg _irepresent the aerial line weight of drill string of i-th drill string Nodes, unit is N/m;

S150: obtain the axial tension of well head drill string and the moment of torsion of well head drill string.

In certain embodiments, the axial tension obtaining well head drill string can comprise: obtain the ground weight indicator reading in real drill-through journey, transmission efficiency that Hoisting System effectively restricts number and single pulley; Effectively restrict according to described ground weight indicator reading, Hoisting System the transmission efficiency determination weight on hook of number and single pulley, described weight on hook is as well head drill string axial tension.Concrete, following design formulas can be utilized:

$\mathrm{WOH}=\mathrm{WOG}\·\frac{(1-{\mathrm{\η}}^n)\mathrm{\η}}{(1-\mathrm{\η})\mathrm{\η}}$

In above formula, WOH represents weight on hook; WOG represents weight indicator reading; N is that Hoisting System is effectively restricted number; η is the transmission efficiency of single pulley.

Further, described well head drill string axial tension is also the drill string axial tension at first measuring point place, is also the drill string axial tension of first drill string Nodes.

Further, described well head drill string torque directly can record in real drill-through journey, and described well head drill string torque is also the drill string torque at first measuring point place, is also the drill string torque of first drill string Nodes.

S160: utilize and preset the drill string tension and torque differential equation, in conjunction with axial tension and the well head drill string torque of the geological information of each drill string node, moment of inertia, line buoyant weight and well head drill string, determines downhole drill parameter.

In certain embodiments, utilize and preset the drill string tension and torque differential equation, in conjunction with axial tension and the well head drill string torque of the geological information of each drill string node, moment of inertia, line buoyant weight and well head drill string, determine downhole drill parameter.Concrete, described default drill string pulling force-moment of torsion differential equation is as follows:

$\left\{\begin{array}{c}\frac{{\mathrm{dM}}_i}{\mathrm{dL}}=f_{1i}{r}_i{N}_i+m_i\\ \frac{{\mathrm{dT}}_i}{\mathrm{dL}}+{\mathrm{EIK}}_{\mathrm{bi}}\frac{{\mathrm{dK}}_{\mathrm{bi}}}{\mathrm{dL}}-f_{2i}{N}_i-C_i{V}_i-B_i+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{t}}_i=0\\ -E_i{I}_i\frac{d^2{K}_{\mathrm{bi}}}{{\mathrm{dL}}^2}+K_{\mathrm{bi}}{T}_i+E_i{I}_i{K}_{\mathrm{ni}}^2{K}_{\mathrm{bi}}+K_{\mathrm{bi}}{K}_{\mathrm{ni}}{M}_i+N_{\mathrm{ni}}+f_{1i}{N}_{\mathrm{bi}}+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{n}}_i=0\\ -\frac{d}{\mathrm{dL}}(E_i{I}_i{K}_{\mathrm{ni}}{K}_{\mathrm{bi}}+K_{\mathrm{bi}}{M}_i)-E_i{I}_i{K}_{\mathrm{ni}}\frac{{\mathrm{dK}}_{\mathrm{bi}}}{\mathrm{dL}}+N_{\mathrm{bi}}-f_{1i}{N}_{\mathrm{ni}}+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{b}}_i=0\end{array}\right.$

Wherein, $f_{1i}=\frac{2{\mathrm{\πr}}_i{\mathrm{\ω}}_i}{\sqrt{{V_i}^2+{\left(2{\mathrm{\πr}}_i{\mathrm{\ω}}_i\right)}^2}}f$

$f_{2i}=\frac{V_i}{\sqrt{{V_i}^2+{\left({2\mathrm{\πr}}_i{\mathrm{\ω}}_i\right)}^2}}f$

${\stackrel{\→}{k}}_i\·{\stackrel{\→}{t}}_i=-\cos {\mathrm{\α}}_i$

${\stackrel{\→}{k}}_i\·{\stackrel{\→}{n}}_i=\frac{1}{K_{\mathrm{bi}}}\frac{d{\mathrm{\α}}_i}{\mathrm{dL}}\sin {\mathrm{\α}}_i$

${\stackrel{\→}{k}}_i\·{\stackrel{\→}{b}}_i=-\frac{1}{K_{\mathrm{bi}}}\frac{d{\mathrm{\φ}}_i}{\mathrm{dL}}{\sin }^2{\mathrm{\α}}_i$

$N_i=\sqrt{N_{\mathrm{ni}}^2+N_{\mathrm{bi}}^2}$

$m_i=\frac{\mathrm{\π}\×{D_i}^3\×{\mathrm{\ω}}_i}{4}\×(\frac{{\mathrm{\τ}}_i}{\sqrt{({V_i}^2+{\left(D_i{\mathrm{\π\ω}}_i\right)}^2)}}+\frac{2\×{\mathrm{\μ}}_i}{D_{\mathrm{Wi}}-D_i})$

$B_i=\frac{D_i{\mathrm{\π\τ}}_i{V}_i}{\sqrt{{V_i}^2+{\left(D_i{\mathrm{\π\ω}}_i\right)}^2}}$

$C_i=\frac{{2\mathrm{\π\μ}}_i}{\ln \left(D_{\mathrm{wi}}\right)-\ln \left(D_i\right)}$

Wherein, M _irepresent the moment of torsion of i-th drill string Nodes, unit is Nm; T _irepresent the drill string axial tension of i-th drill string Nodes, unit is N; N _irepresent the normal pressure between i-th drill string Nodes drill string and the borehole wall, unit is N; N _birepresent N _iin subnormal durection component, unit is N; N _nirepresent N _iin principal normal durection component, unit is N; m _irepresent the external torque that mud produces, unit is Nm; f _1irepresent i-th drill string Nodes circumference friction factor; B _irepresent the axial force that i-th drill string Nodes mud shear force produces, unit is N; C _irepresent the axial force that i-th drill string Nodes mud viscosity produces, unit is N; f _2irepresent i-th drill string Nodes axial rub coefficient; g _irepresent the line buoyant weight of i-th drill string Nodes, unit is N/m; represent the component of i-th drill string Nodes line buoyant weight tangential direction, unit is N/m; represent the component in i-th drill string Nodes line buoyant weight principal normal direction, unit is N/m; represent the component in i-th drill string Nodes line buoyant weight binormal direction, unit is N/m; represent the rate of deviation of i-th drill string Nodes drill string; represent i-th drill string Nodes drill string rate of azimuth change; I _irepresent i-th drill string Nodes drill string moment of inertia, unit is m ⁴; K _birepresent i-th drill string Nodes drill string curvature, unit is 1/m; K _nirepresent i-th drill string Nodes drill string torsion, unit is 1/m.

In addition, also comprise in above-mentioned formula: f represents frictional coefficient; V _ibe that i-th drill string Nodes pulls out of hole or speed uplink, unit is m/s; ω _irepresent i-th drill string Nodes drill string rotating speed, unit is 1/s; τ _irepresent i-th drill string Nodes drilling fluid yield value, unit is pa; μ _irepresent drilling fluid viscosity, unit is pas; E _irepresent the modulus of elasticity of i-th drill string Nodes drill string steel, unit is pa; L represents drill string length, and unit is m; α _irepresent i-th drill string Nodes drill string hole angle; D _wirepresent i-th drill string Nodes borehole diameter, unit is m; D _irepresent i-th drill string Nodes drill string external diameter, unit is m.These data can obtain in real drill-through journey.

By the data obtained in the drill-through journey of above-mentioned reality of each drill string node and calculate the geological information of drill string node, the moment of inertia of described drill string node, the line buoyant weight of described drill string node, described well head drill string axial tension and the described well head drill string torque that obtain and substitute into the drill string torque increment that the described default drill string tension and torque differential equation can determine each drill string Nodes successively the drill string axial tension increment of each drill string Nodes and the friction drag increment f of each drill string Nodes _2in _i+ C _iv _i+ B _i.The friction drag increment obtaining each drill string Nodes can comprise: determine the normal pressure N between each drill string Nodes drill string and the borehole wall according to the described default drill string tension and torque differential equation _iat subnormal durection component N _bi, and the normal pressure N between each drill string Nodes drill string and the borehole wall _iat principal normal durection component N _ni, and according to the normal pressure N between each drill string Nodes drill string and the borehole wall _iat subnormal durection component N _bi, and the normal pressure N between each drill string Nodes drill string and the borehole wall _iat principal normal durection component N _nidetermine the normal pressure N between drill string and the borehole wall _i, and then the friction drag increment f of each drill string Nodes can be obtained _2in _i+ C _iv _i+ B _i.

In certain embodiments, the moment of torsion of each drill string node can be determined according to following formula, and using distance well head apart from the moment of torsion of maximum drill string node as torque-on-bit:

M _i＝M _i-1+ΔM _i

In above formula, M _irepresent the moment of torsion of i-th drill string Nodes; M _i-1represent the moment of torsion of the i-th-1 drill string Nodes; Δ M _irepresenting the drill string torque increment of i-th drill string Nodes, is also in the described default drill string tension and torque differential equation wherein, the distance between i-th drill string node and well head is greater than the distance between the i-th-1 drill string node and well head; As i=1, M ₁represent well head drill string torque.

In certain embodiments, the axial tension of each drill string node can be determined according to following formula, and using distance well head apart from the axial tension of maximum drill string node as drill bit axial tension:

T _i＝T _i-1+ΔT _i

In above formula, T _irepresent the drill string axial tension of i-th drill string Nodes; T _i-1represent the drill string axial tension of the i-th-1 drill string Nodes; Δ T _irepresenting the drill string axial tension increment of i-th drill string Nodes, is also in the described default drill string tension and torque differential equation as i=1, T ₁represent well head drill string axial tension.

In certain embodiments, can according to the friction drag of following formula determination drill string:

F＝F ₁+F ₂+...+F _i-1+F _i

In above formula, F represents drill string friction drag; F _irepresent the friction drag of i-th drill string Nodes; F _i-1represent the friction drag of the i-th-1 drill string Nodes; Wherein, F _i=f _2in _i+ C _iv _i+ B _i.

In certain embodiments, when drillstring motion state is slipping drilling, drill bit axial tension, drill string friction drag can be obtained as downhole drill parameter; When drillstring motion state is rotary drilling, torque-on-bit, drill bit axial tension can be obtained as downhole drill parameter.

As can be seen here, the technical scheme of the embodiment of a kind of downhole drill determination method for parameter of the application by successively determining drill string node from well head to drill bit direction according to presetting step-length, and obtains the moment of torsion of the geological information of described drill string node, the moment of inertia of drill string node, the line buoyant weight of drill string node, the axial tension of well head drill string and well head drill string.Then utilize and preset the moment of torsion acquisition downhole drill parameter of the drill string tension and torque differential equation in conjunction with the line buoyant weight of the moment of inertia of the geological information of described drill string node, described drill string node, described drill string node, the axial tension of described well head drill string and described well head drill string.Described downhole drill parameter information and surface data are carried out organic combination, can realize more rationally, Drilling optimization operation more efficiently, real-time diagnosis underground working.

The application also provides on the other hand a kind of determining device of downhole drill parameter, and by reference to the accompanying drawings 2, this device 200 comprises:

Drill string node determining unit 210, for successively determining drill string node from well head to drill bit direction according to presetting step-length;

Computing unit 220, for obtaining the well deviational survey data of each measuring point, and according to the rate of deviation of drill string node between every two measuring points of described well deviational survey data calculating and the rate of azimuth change of drill string node;

First data determination unit 230, for combining the rate of deviation and rate of azimuth change that calculate, determines the geological information of each drill string node;

Second data determination unit 240, for determining moment of inertia and the line buoyant weight of each drill string node;

Well head data capture unit 250, for the moment of torsion of the axial tension and well head drill string that obtain well head drill string;

Downhole drill parameter determination unit 260, for utilizing the default drill string tension and torque differential equation, in conjunction with axial tension and the well head drill string torque of the geological information of each drill string node, moment of inertia, line buoyant weight and well head drill string, determines downhole drill parameter.

In a preferred embodiment, described well deviational survey data comprise: hole angle, azimuth and well depth.

In a preferred embodiment, described geological information comprises: the rate of change of hole angle, azimuth, drill string curvature, drill string curvature variation, drill string curvature variation, drill string torsion and drill string torsion rate of change.

In a preferred embodiment, described second data determination unit 240 comprises:

First computing module, for the drill string internal diameter of the drill string external diameter and described drill string Nodes that obtain described drill string Nodes, and calculates the moment of inertia of drill string node according to described drill string external diameter and described drill string internal diameter;

Second computing module, for obtaining the aerial line weight of drill string of the drilling fluid density of described drill string Nodes, the drill string steel density of described drill string Nodes and described drill string Nodes, and according to the line buoyant weight of described drilling fluid density, described drill string steel density and described drill string aerial line re-computation drill string node.

In a preferred embodiment, described second data determination unit 240 comprises:

First data acquisition module, for obtaining the transmission efficiency that well head drill string axial tension obtains ground weight indicator reading in real drill-through journey, Hoisting System effectively restricts number and single pulley;

First data determining module, for the transmission efficiency determination weight on hook of effectively restrict according to described ground weight indicator reading, Hoisting System number and single pulley, and using described weight on hook as well head drill string axial tension.

In a preferred embodiment, described downhole drill parameter comprises: drill bit axial tension and torque-on-bit.

In a preferred embodiment, described downhole drill parameter also comprises: drill bit axial tension, drill string friction drag.

In a preferred embodiment, the described default drill string tension and torque differential equation is as follows:

$\left\{\begin{array}{c}\frac{{\mathrm{dM}}_i}{\mathrm{dL}}=f_{1i}{r}_i{N}_i+m_i\\ \frac{{\mathrm{dT}}_i}{\mathrm{dL}}+{\mathrm{EIK}}_{\mathrm{bi}}\frac{{\mathrm{dK}}_{\mathrm{bi}}}{\mathrm{dL}}-f_{2i}{N}_i-C_i{V}_i-B_i+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{t}}_i=0\\ -E_i{I}_i\frac{d^2{K}_{\mathrm{bi}}}{{\mathrm{dL}}^2}+K_{\mathrm{bi}}{T}_i+E_i{I}_i{K}_{\mathrm{ni}}^2{K}_{\mathrm{bi}}+K_{\mathrm{bi}}{K}_{\mathrm{ni}}{M}_i+N_{\mathrm{ni}}+f_{1i}{N}_{\mathrm{bi}}+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{n}}_i=0\\ -\frac{d}{\mathrm{dL}}(E_i{I}_i{K}_{\mathrm{ni}}{K}_{\mathrm{bi}}+K_{\mathrm{bi}}{M}_i)-E_i{I}_i{K}_{\mathrm{ni}}\frac{{\mathrm{dK}}_{\mathrm{bi}}}{\mathrm{dL}}+N_{\mathrm{bi}}-f_{1i}{N}_{\mathrm{ni}}+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{b}}_i=0\end{array}\right.$

Wherein, $f_{1i}=\frac{2{\mathrm{\πr}}_i{\mathrm{\ω}}_i}{\sqrt{{V_i}^2+{\left(2{\mathrm{\πr}}_i{\mathrm{\ω}}_i\right)}^2}}f;$ $f_{2i}=\frac{V_i}{\sqrt{{V_i}^2+{\left({2\mathrm{\πr}}_i{\mathrm{\ω}}_i\right)}^2}}f;$ ${\stackrel{\→}{k}}_i\·{\stackrel{\→}{t}}_i=-\cos {\mathrm{\α}}_i;$ ${\stackrel{\→}{k}}_i\·{\stackrel{\→}{n}}_i=\frac{1}{K_{\mathrm{bi}}}\frac{d{\mathrm{\α}}_i}{\mathrm{dL}}\sin {\mathrm{\α}}_i;$ ${\stackrel{\→}{k}}_i\·{\stackrel{\→}{b}}_i=-\frac{1}{K_{\mathrm{bi}}}\frac{d{\mathrm{\φ}}_i}{\mathrm{dL}}{\sin }^2{\mathrm{\α}}_i;$ $N_i=\sqrt{N_{\mathrm{ni}}^2+N_{\mathrm{bi}}^2};$

$m_i=\frac{\mathrm{\π}\×{D_i}^3\×{\mathrm{\ω}}_i}{4}\×(\frac{{\mathrm{\τ}}_i}{\sqrt{({V_i}^2+{\left(D_i{\mathrm{\π\ω}}_i\right)}^2)}}+\frac{2\×{\mathrm{\μ}}_i}{D_{\mathrm{Wi}}-D_i});$ $B_i=\frac{D_i{\mathrm{\π\τ}}_i{V}_i}{\sqrt{{V_i}^2+{\left(D_i{\mathrm{\π\ω}}_i\right)}^2}};$

$C_i=\frac{{2\mathrm{\π\μ}}_i}{\ln \left(D_{\mathrm{wi}}\right)-\ln \left(D_i\right)}$

Wherein, M _irepresent the moment of torsion of i-th drill string Nodes, unit is Nm; T _irepresent the drill string axial tension of i-th drill string Nodes, unit is N; N _irepresent the normal pressure between i-th drill string Nodes drill string and the borehole wall, unit is N; N _birepresent N _iin subnormal durection component, unit is N; N _nirepresent N _iin principal normal durection component, unit is N; m _irepresent the external torque that mud produces, unit is Nm; f _1irepresent i-th drill string Nodes circumference friction factor; B _irepresent the axial force that i-th drill string Nodes mud shear force produces, unit is N; C _irepresent the axial force that i-th drill string Nodes mud viscosity produces, unit is N; f _2irepresent i-th drill string Nodes axial rub coefficient; g _irepresent the line buoyant weight of i-th drill string Nodes, unit is N/m; represent the component of i-th drill string Nodes line buoyant weight tangential direction, unit is N/m; represent the component in i-th drill string Nodes line buoyant weight principal normal direction, unit is N/m; represent the component in i-th drill string Nodes line buoyant weight binormal direction, unit is N/m; represent the rate of deviation of i-th drill string Nodes drill string; represent i-th drill string Nodes drill string rate of azimuth change; I _irepresent i-th drill string Nodes drill string moment of inertia, unit is m ⁴; K _birepresent i-th drill string Nodes drill string curvature, unit is 1/m; K _nirepresent i-th drill string Nodes drill string torsion, unit is 1/m; F represents frictional coefficient; V _ibe that i-th drill string Nodes pulls out of hole or speed uplink, unit is m/s; ω _irepresent i-th drill string Nodes drill string rotating speed, unit is 1/s; τ _irepresent i-th drill string Nodes drilling fluid yield value, unit is pa; μ _irepresent drilling fluid viscosity, unit is pas; E _irepresent the modulus of elasticity of i-th drill string Nodes drill string steel, unit is pa; L represents drill string length, and unit is m; α _irepresent i-th drill string Nodes drill string hole angle; D _wirepresent i-th drill string Nodes borehole diameter, unit is m; D _irepresent i-th drill string Nodes drill string external diameter, unit is m.

In a preferred embodiment, describedly determine that downhole drill parameter comprises:

According to the drill string torque increment of described default drill string tension and torque differential equation determination drill string Nodes, the drill string axial tension increment of drill string Nodes and the friction drag increment of drill string Nodes;

Determine the moment of torsion of each drill string node according to following formula, and using distance well head apart from the moment of torsion of maximum drill string node as torque-on-bit:

M _i＝M _i-1+ΔM _i

In above formula, M _irepresent the moment of torsion of i-th drill string Nodes; M _i-1represent the moment of torsion of the i-th-1 drill string Nodes; Δ M _irepresent the drill string torque increment of i-th drill string Nodes, wherein, the distance between i-th drill string node and well head is greater than the distance between the i-th-1 drill string node and well head;

Determine the axial tension of each drill string node according to following formula, and using distance well head apart from the axial tension of maximum drill string node as drill bit axial tension:

T _i＝T _i-1+ΔT _i

In above formula, T _irepresent the drill string axial tension of i-th drill string Nodes; T _i-1represent the drill string axial tension of the i-th-1 drill string Nodes; Δ T _irepresent the drill string axial tension increment of i-th drill string Nodes;

Friction drag according to following formula determination drill string::

F＝F ₁+F ₂+...+F _i-1+F _i

In above formula, F represents drill string friction drag; F _irepresent the friction drag of i-th drill string Nodes; F _i-1represent the friction drag of the i-th-1 drill string Nodes; Wherein, F _i=f _2in _i+ C _iv _i+ B _i.

From the embodiment of a kind of downhole drill determination method for parameter of above the application and device, the technical scheme that the embodiment of the present application provides by successively determining drill string node from well head to drill bit direction according to presetting step-length, and obtains the moment of torsion of the geological information of described drill string node, the moment of inertia of drill string node, the line buoyant weight of drill string node, the axial tension of well head drill string and well head drill string.Then utilize and preset the moment of torsion acquisition downhole drill parameter of the drill string tension and torque differential equation in conjunction with the line buoyant weight of the moment of inertia of the geological information of described drill string node, described drill string node, described drill string node, the axial tension of described well head drill string and described well head drill string.Described downhole drill parameter information and surface data are carried out organic combination, can realize more rationally, Drilling optimization operation more efficiently, real-time diagnosis underground working.

Each embodiment in this manual all adopts the mode of going forward one by one to describe, and what each embodiment stressed is the difference with other embodiments, between each embodiment identical similar part mutually see.Especially, for system embodiment, because it is substantially similar to embodiment of the method, so description is fairly simple, relevant part illustrates see the part of embodiment of the method.

Although depict the application by embodiment, those of ordinary skill in the art know, the application has many distortion and change and do not depart from the spirit of the application, and the claim appended by wishing comprises these distortion and change and do not depart from the spirit of the application.

Claims (10)

1. a downhole drill determination method for parameter, is characterized in that, the method comprises:

Drill string node is determined from well head successively to drill bit direction according to default step-length;

Obtain the well deviational survey data of each measuring point, and according to the rate of deviation of drill string node between every two measuring points of described well deviational survey data calculating and the rate of azimuth change of drill string node;

In conjunction with the rate of deviation calculated and rate of azimuth change, determine the geological information of each drill string node;

Determine moment of inertia and the line buoyant weight of each drill string node;

Obtain the axial tension of well head drill string and the moment of torsion of well head drill string;

Utilize and preset the drill string tension and torque differential equation, in conjunction with axial tension and the well head drill string torque of the geological information of each drill string node, moment of inertia, line buoyant weight and well head drill string, determine downhole drill parameter.

2. method according to claim 1, is characterized in that, described well deviational survey data comprise: hole angle, azimuth and well depth.

3. method according to claim 1, is characterized in that, described geological information comprises: the rate of change of hole angle, azimuth, drill string curvature, drill string curvature variation, drill string curvature variation, drill string torsion and drill string torsion rate of change.

4. method according to claim 1, is characterized in that, describedly determines that the moment of inertia of each drill string node and line buoyant weight comprise:

Obtain the drill string external diameter of described drill string Nodes and the drill string internal diameter of described drill string Nodes, and calculate the moment of inertia of drill string node according to described drill string external diameter and described drill string internal diameter;

Obtain the drilling fluid density of described drill string Nodes, the drill string steel density of described drill string Nodes and the aerial line weight of drill string of described drill string Nodes, and according to the line buoyant weight of described drilling fluid density, described drill string steel density and described drill string aerial line re-computation drill string node.

5. method according to claim 1, is characterized in that, the axial tension of described acquisition well head drill string comprises:

Obtain the ground weight indicator reading in real drill-through journey, transmission efficiency that Hoisting System effectively restricts number and single pulley;

Effectively to restrict according to described ground weight indicator reading, Hoisting System the transmission efficiency determination weight on hook of number and single pulley, and using described weight on hook as well head drill string axial tension.

6. method according to claim 1, is characterized in that, described downhole drill parameter comprises: drill bit axial tension and torque-on-bit.

7. method according to claim 1, is characterized in that, described downhole drill parameter also comprises: drill bit axial tension and drill string friction drag.

8. the method according to claim 6 or 7, is characterized in that, the described default drill string tension and torque differential equation is as follows:

$\left\{\begin{array}{c}\frac{d{M}_i}{\mathrm{dL}}=f_{1i}{r}_i{N}_i+m_i\\ \frac{d{T}_i}{\mathrm{dL}}+{\mathrm{EIK}}_{\mathrm{bi}}\frac{{\mathrm{dK}}_{\mathrm{bi}}}{\mathrm{dL}}-f_{2i}{N}_i-C_i{V}_i-B_i+g_i\stackrel{\→}{k_i}\·\stackrel{\→}{t_i}=0\\ -E_i{I}_i\frac{d^2{K}_{\mathrm{bi}}}{d{L}^2}+K_{\mathrm{bi}}{T}_i+E_i{I}_i{K}_{\mathrm{ni}}^2{K}_{\mathrm{bi}}+K_{\mathrm{bi}}{K}_{\mathrm{ni}}{M}_i+N_{\mathrm{ni}}+f_{1i}{N}_{\mathrm{bi}}+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{n}}_i=0\\ -\frac{d}{\mathrm{dL}}(E_i{I}_i{K}_{\mathrm{ni}}{K}_{\mathrm{bi}}+K_{\mathrm{bi}}{M}_i)-E_i{I}_i{K}_{\mathrm{ni}}\frac{d{K}_{\mathrm{bi}}}{\mathrm{dL}}+N_{\mathrm{bi}}-f_{1i}{N}_{\mathrm{ni}}+g_i{\stackrel{\→}{k}}_i\·{\stackrel{\→}{b}}_i=0\end{array}\right.$

Wherein, $f_{1i}=\frac{2\mathrm{\π}{r}_i{\mathrm{\ω}}_i}{\sqrt{V_i^2+{\left(2\mathrm{\π}{r}_i{\mathrm{\ω}}_i\right)}^2}}f;f_{2i}=\frac{V_i}{\sqrt{V_i^2+{\left(2\mathrm{\π}{r}_i{\mathrm{\ω}}_i\right)}^2}}f;{\stackrel{\→}{k}}_i\·{\stackrel{\→}{t}}_i=-\cos {\mathrm{\α}}_i;$

${\stackrel{\→}{k}}_i\·{\stackrel{\→}{n}}_i=\frac{1}{K_{\mathrm{bi}}}\frac{d{\mathrm{\α}}_i}{\mathrm{dL}}\sin {\mathrm{\α}}_i;{\stackrel{\→}{k}}_i\·{\stackrel{\→}{b}}_i=-\frac{1}{K_{\mathrm{bi}}}\frac{d{\mathrm{\φ}}_i}{\mathrm{dL}}{\sin }^2{\mathrm{\α}}_i;N_i=\sqrt{N_{\mathrm{ni}}^2+N_{\mathrm{bi}}^2};$

$m_i=\frac{\mathrm{\π}\×D_i^3\×{\mathrm{\ω}}_i}{4}\×(\frac{{\mathrm{\τ}}_i}{\sqrt{(V_i^2+{\left(D_i\mathrm{\π}{\mathrm{\ω}}_i\right)}^2)}}+\frac{2\×{\mathrm{\μ}}_i}{D_{\mathrm{Wi}}-D_i});B_i=\frac{D_i\mathrm{\π}{\mathrm{\τ}}_i{V}_i}{\sqrt{V_i^2+{\left(D_i\mathrm{\π}{\mathrm{\ω}}_i\right)}^2}};$

$C_i=\frac{2\mathrm{\π}{\mathrm{\μ}}_i}{\ln \left(D_{\mathrm{wi}}\right)-\ln \left(D_i\right)}$

Wherein, M _irepresent the moment of torsion of i-th drill string Nodes, unit is Nm; T _irepresent the drill string axial tension of i-th drill string Nodes, unit is N; N _irepresent the normal pressure between i-th drill string Nodes drill string and the borehole wall, unit is N; N _birepresent N _iin subnormal durection component, unit is N; N _nirepresent N _iin principal normal durection component, unit is N; m _irepresent the external torque that mud produces, unit is Nm; f _1irepresent i-th drill string Nodes circumference friction factor; B _irepresent the axial force that i-th drill string Nodes mud shear force produces, unit is N; C _irepresent the axial force that i-th drill string Nodes mud viscosity produces, unit is N; f _2irepresent i-th drill string Nodes axial rub coefficient; g _irepresent the line buoyant weight of i-th drill string Nodes, unit is N/m; represent the component of i-th drill string Nodes line buoyant weight tangential direction, unit is N/m; represent the component in i-th drill string Nodes line buoyant weight principal normal direction, unit is N/m; represent the component in i-th drill string Nodes line buoyant weight binormal direction, unit is N/m; represent the rate of deviation of i-th drill string Nodes drill string; represent i-th drill string Nodes drill string rate of azimuth change; I _irepresent i-th drill string Nodes drill string moment of inertia, unit is m ⁴; K _birepresent i-th drill string Nodes drill string curvature, unit is 1/m; K _nirepresent i-th drill string Nodes drill string torsion, unit is 1/m; F represents frictional coefficient; V _ibe that i-th drill string Nodes pulls out of hole or speed uplink, unit is m/s; ω _irepresent i-th drill string Nodes drill string rotating speed, unit is 1/s; τ _irepresent i-th drill string Nodes drilling fluid yield value, unit is pa; μ _irepresent drilling fluid viscosity, unit is pas; E _irepresent the modulus of elasticity of i-th drill string Nodes drill string steel, unit is pa; L represents drill string length, and unit is m; α _irepresent i-th drill string Nodes drill string hole angle; D _wirepresent i-th drill string Nodes borehole diameter, unit is m; D _irepresent i-th drill string Nodes drill string external diameter, unit is m.

9. method according to claim 8, is characterized in that, describedly determines that downhole drill parameter comprises:

According to the drill string torque increment of described default drill string tension and torque differential equation determination drill string Nodes, the drill string axial tension increment of drill string Nodes and the friction drag increment of drill string Nodes;

Determine the moment of torsion of each drill string node according to following formula, and using distance well head apart from the moment of torsion of maximum drill string node as torque-on-bit:

M _i＝M _i-1+ΔM _i

In above formula, M _irepresent the moment of torsion of i-th drill string Nodes; M _i-1represent the moment of torsion of the i-th-1 drill string Nodes; Δ M _irepresent the drill string torque increment of i-th drill string Nodes, wherein, the distance between i-th drill string node and well head is greater than the distance between the i-th-1 drill string node and well head;

Determine the axial tension of each drill string node according to following formula, and using distance well head apart from the axial tension of maximum drill string node as drill bit axial tension:

T _i＝T _i-1+ΔT _i

In above formula, T _irepresent the drill string axial tension of i-th drill string Nodes; T _i-1represent the drill string axial tension of the i-th-1 drill string Nodes; Δ T _irepresent the drill string axial tension increment of i-th drill string Nodes;

Friction drag according to following formula determination drill string::

F＝F ₁+F ₂+...+F _i-1+F _i

In above formula, F represents drill string friction drag; F _irepresent the friction drag of i-th drill string Nodes; F _i-1represent the friction drag of the i-th-1 drill string Nodes; Wherein, F _i=f _2in _i+ C _iv _i+ B _i.

10. a determining device for downhole drill parameter, is characterized in that, this device comprises:

Drill string node determining unit, for successively determining drill string node from well head to drill bit direction according to presetting step-length;

Computing unit, for obtaining the well deviational survey data of each measuring point, and according to the rate of deviation of drill string node between every two measuring points of described well deviational survey data calculating and the rate of azimuth change of drill string node;

First data determination unit, for combining the rate of deviation and rate of azimuth change that calculate, determines the geological information of each drill string node;

Second data determination unit, for determining moment of inertia and the line buoyant weight of each drill string node;

Well head data capture unit, for the moment of torsion of the axial tension and well head drill string that obtain well head drill string;

Downhole drill parameter determination unit, for utilizing the default drill string tension and torque differential equation, in conjunction with axial tension and the well head drill string torque of the geological information of each drill string node, moment of inertia, line buoyant weight and well head drill string, determines downhole drill parameter.