CN103557513B - A kind of H type economizer based on longitudinal Vortex - Google Patents
A kind of H type economizer based on longitudinal Vortex Download PDFInfo
- Publication number
- CN103557513B CN103557513B CN201310545617.7A CN201310545617A CN103557513B CN 103557513 B CN103557513 B CN 103557513B CN 201310545617 A CN201310545617 A CN 201310545617A CN 103557513 B CN103557513 B CN 103557513B
- Authority
- CN
- China
- Prior art keywords
- fin
- heat transfer
- fluid
- water
- heat
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000012546 transfer Methods 0.000 claims abstract description 79
- 239000012530 fluid Substances 0.000 claims abstract description 49
- 230000000694 effects Effects 0.000 claims abstract description 9
- 229910052751 metal Inorganic materials 0.000 claims abstract description 7
- 239000002184 metal Substances 0.000 claims abstract description 7
- 150000002739 metals Chemical class 0.000 claims abstract description 5
- 210000000746 body region Anatomy 0.000 claims abstract description 4
- 238000003466 welding Methods 0.000 claims abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 30
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 20
- 239000003546 flue gas Substances 0.000 claims description 20
- 238000000034 method Methods 0.000 claims description 15
- 238000012360 testing method Methods 0.000 claims description 11
- 230000008676 import Effects 0.000 claims description 10
- 235000019504 cigarettes Nutrition 0.000 claims description 5
- 239000003517 fume Substances 0.000 claims description 4
- 238000009529 body temperature measurement Methods 0.000 claims description 2
- 239000000567 combustion gas Substances 0.000 claims description 2
- 238000002485 combustion reaction Methods 0.000 claims description 2
- 238000009792 diffusion process Methods 0.000 claims description 2
- 230000003068 static effect Effects 0.000 claims description 2
- 238000001514 detection method Methods 0.000 claims 1
- 238000011156 evaluation Methods 0.000 claims 1
- 238000009826 distribution Methods 0.000 description 8
- 238000010586 diagram Methods 0.000 description 6
- 238000013316 zoning Methods 0.000 description 6
- 230000008859 change Effects 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 4
- 238000004088 simulation Methods 0.000 description 4
- 230000003416 augmentation Effects 0.000 description 3
- 230000004888 barrier function Effects 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 230000007246 mechanism Effects 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004422 calculation algorithm Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000009795 derivation Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
- 238000013517 stratification Methods 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
Landscapes
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
The invention discloses a kind of H type economizer based on longitudinal Vortex, comprise several and be arranged in order H type fin, the equal vertical welding of described fin is on extended surface tube, the part metals carrying out flow path direction of each described fin forms some fins upwards dug, and described fin and fin surface are carried out flow path direction and formed the angle of attack; A series of longitudinal Vortex can be produced when fluid flows through the extended surface tube passage being provided with fin, under the effect of longitudinal Vortex, fluid has had the component velocity perpendicular to main flow direction, this component velocity accelerates mixing of main flow area and fluid near the heat transfer wall of fin, promote fluid and the momentum of body region fluid and the exchange of energy near fin heat transfer wall, make boundary layer thinning or destroyed, reduce heat transfer resistance, improve convective heat-transfer coefficient.
Description
Technical field
The present invention relates to a kind of H type economizer based on longitudinal Vortex.
Background technology
Heat exchanger carries out exchange heat as different temperatures fluid media (medium) and realizes heating or cooling the common apparatus of object, is widely used in each department of national economy.The quality of heat exchanger performance, the height of heat transfer coefficient are directly connected to the utilization ratio of the energy.Application heat transfer enhancement technology, improves heat exchanger heat transfer usefulness, reduces heat exchanger metal wastage and initial cost, reduces heat exchanger operation energy consumption, and to realizing energy-saving and emission-reduction, sustainable development has important practical significance.
As a kind of enhanced heat transfer component of high-efficiency compact, extended surface tube obtains general commercial Application.Restrain to the economizer in thermal power plant greatly, the little heat-pipe radiator to cooling computer chip, is widely used in the fields such as electric power, chemical industry, refrigeration, electronic device cooling with the heat exchanger that extended surface tube is main heat exchange element.By processing the fin of projection on fin---long direction eddy generator, heat exchanging fluid flows through fin surface, a series of longitudinal Vortex can be produced at long direction eddy generator afterbody, the momentum and energy that these longitudinal Vortexes strengthen fluid and main flow area fluid near heat transfer wall exchanges, and carrys out enhanced heat exchange by the change distribution of Secondary Flow and the concertedness in velocity field and temperature field.Long direction eddy generator, as the passive enhanced heat exchange mode of one, can obtain larger augmentation of heat transfer effect with relatively little drag losses, become one of study hotspot.
Along with the strict of national environmental protection policy is implemented, the out of stock transformation of flue gas in power station boiler has become the required course of Large-scale fire-electricity unit.And in practical implementation, after one of technical barrier faced by Thermal Power Enterprises is economizer, cigarette temperature is too high, beyond the reaction temperature of out of stock catalyst, make it to produce effect.The best approach solving this difficult problem is exactly improve the overall heat transfer property of economizer, increases heat exchange amount, reduces the flue-gas temperature after its heat exchange.Therefore, the heat transfer enhancement technology adopting some new has great significance to the heat transfer characteristic improving economizer heat transfer element for unit safety, stable, economical operation.
Summary of the invention
Object of the present invention is exactly to solve the problem, and provides a kind of H type economizer based on longitudinal Vortex, makes it the heat exchange total amount improving economizer under the prerequisite of same space and same metal consumption, reduces exhaust gas temperature.
To achieve these goals, the present invention adopts following technical scheme:
A kind of H type economizer based on longitudinal Vortex, comprise several and be arranged in order H type fin, the equal vertical welding of described H type fin is on extended surface tube, the part metals carrying out flow path direction of each described H type fin forms some fins upwards dug, and described fin and H type fin surface are carried out flow path direction and formed the angle of attack; A series of longitudinal Vortex can be produced when fluid flows through the extended surface tube passage being provided with fin, under the effect of longitudinal Vortex, fluid has had the component velocity perpendicular to main flow direction, this component velocity accelerates mixing of main flow area and fluid near the heat transfer wall of H type fin, promote fluid and the momentum of body region fluid and the exchange of energy near H type fin heat transfer wall, make boundary layer thinning or destroyed, reduce heat transfer resistance, improve convective heat-transfer coefficient.
The angle of the described angle of attack is 30 °-60 °.
The fin number of each described H type fin is 2-4.
At least 2 described fins are distributed in the upper left corner and the upper right corner of H type fin respectively.
At least 2 described fins are distributed in the upper left corner and the lower right corner of H type fin respectively.
At least 2 described fins are distributed in the lower left corner and the upper right corner of H type fin respectively.
At least 2 described fins are distributed in the lower left corner and the lower right corner of H type fin respectively.
Beneficial effect of the present invention:
1 the present invention can change the distribution of fin rear Secondary Flow and the concertedness in velocity field and temperature field, significantly improves the surface coefficient of heat transfer of fin heat transfer wall;
2 the present invention can improve the heat exchange total amount of economizer under the prerequisite of same space and same metal consumption, and reduce exhaust gas temperature, energy-saving effect is remarkable;
3 the present invention can form longitudinal Vortex on fin surface, reduce dust stratification, improve relevant device reliability of operation;
4 processing technologys of the present invention are simple, and production efficiency is high, and manufacturing cost is quite front with optimization.
Accompanying drawing explanation
Fig. 1 is extended surface tube economizer physical model slice map;
Fig. 2 is the heat-transfer character comparison diagram of straight fin and different angle of attack fin;
Fig. 3 is the drag characteristic comparison diagram of straight fin and different angle of attack fin;
Fig. 4 is the complex heat transfer performance PEC value comparison diagram of straight fin and different angle of attack fin;
Fig. 5 is for optimizing the outer Y-direction velocity field distribution map of rear (with fin) extended surface tube pipe;
Fig. 6 is the outer Y-direction velocity field distribution map of straight extended surface tube pipe;
Fig. 7 is for optimizing the outer thermo parameters method figure of rear (with fin) extended surface tube;
Fig. 8 is the outer thermo parameters method figure of straight extended surface tube;
Fig. 9 is straight fin and β=30 ° angle of attack fin heat-transfer character comparison of test results figure under different velocity in pipes;
Figure 10 is straight fin and β=30 ° angle of attack fin drag characteristic comparison of test results figure under different velocity in pipes.
Detailed description of the invention
Below in conjunction with accompanying drawing and embodiment, the invention will be further described.
A kind of H type economizer based on longitudinal Vortex, comprise several and be arranged in order H type fin, the equal vertical welding of described H type fin is on extended surface tube, the part metals carrying out flow path direction of each described H type fin forms some fins upwards dug, and described fin and H type fin surface are carried out flow path direction and formed the angle of attack; A series of longitudinal Vortex can be produced when fluid flows through the extended surface tube passage being provided with fin, under the effect of longitudinal Vortex, fluid has had the component velocity perpendicular to main flow direction, this component velocity accelerates mixing of main flow area and fluid near the heat transfer wall of H type fin, through H type fin heat transfer wall after fluid chemical field, promote fluid and the momentum of body region fluid and the exchange of energy near H type fin heat transfer wall, make boundary layer thinning or destroyed, reduce heat transfer resistance, improve convective heat-transfer coefficient.
The angle of the described angle of attack is 30 °-60 °.
The fin number of each described H type fin is 2-4.
Embodiment 1: at least 2 described fin is distributed in the upper left corner and the upper right corner of H type fin respectively.
Embodiment 2: at least 2 described fins are distributed in the upper left corner and the lower right corner of H type fin respectively.
Embodiment 3: at least 2 described fins are distributed in the lower left corner and the upper right corner of H type fin respectively.
Embodiment 4: at least 2 described fins are distributed in the lower left corner and the lower right corner of H type fin respectively.
Classical theory thinks that the mechanism of longitudinal whorl strengthened heat convection is:
When viscous fluid flows through the passage placing straight extended surface tube, fluid is not almost having component velocity perpendicular on the direction of main flow, so can only rely on macroviscosity and the heat transfer of molecule in wall normal orientation, the exchange of such momentum and energy is very weak.And when viscous fluid flows through the extended surface tube passage placed with fin, under the secondary flow effects such as longitudinal Vortex, fluid has had the component velocity perpendicular to main flow direction, this component velocity accelerates mixing of main flow area and fluid near heat transfer wall, facilitate the exchange of momentum between the two and energy, make boundary layer thinning or destroyed, reduce heat transfer resistance, effectively improve convective heat-transfer coefficient.
Field-synergy theory thinks that the mechanism of longitudinal whorl strengthened heat convection is:
Cross the angle re-examine heat convection physical mechanism increasing first academician and cooperatively interact from Flow and heat flux, propose the field coordination principle of enhanced heat transfer on this basis, disclose the physical essence of existing various heat convection and augmentation of heat transfer phenomenon.
Explain field coordination principle for two-dimensional layer laminar boundary layer/passage flow model, final derivation equation is
In formula, Nu is nusselt number, and Re is Reynolds number, and Pr is Prandtl number, and U is speed, and T is temperature, and θ is the angle of velocity and thermograde.
Can find out in formula, the flow velocity of alter, the temperature difference, physical property and Re number, Pr number etc. all can reach the object controlling convection heat transfer intensity., can also see from the vector dot product item this formula, the intensity of angle theta to heat convection of velocity and thermograde plays an important role meanwhile.When their angle theta is less than 90 °, heat transfer coefficient reduces along with θ and increases gradually, can reach its maximum when θ=0 °.Can say that the intensity of heat convection not only depends on flow velocity, the temperature difference and physical properties of fluids, also depend on cooperatively interacting of velocity field and heat flow field.
Viewed from vector, this is the collaborative of speed and hot-fluid vector two fields, then has three fields: the cosine value of speed absolute value, hot-fluid absolute value and both angles, only have and heat transfer property just can be made obviously to improve when three obtains larger value simultaneously viewed from scalar.
When viscous fluid flows through the built-in extended surface tube passage with fin, the more straight fin of angle theta of velocity and thermograde obviously reduces, and improves the concertedness in velocity field and temperature field, effectively improves convective heat-transfer coefficient.
As shown in Figure 1, adopting CFD(ComputationalFluidDynamics) the right H type extended surface tube of method for numerical simulation flows outward and heat-transfer character calculates, result shows that installing fin additional can change the distribution of its rear Secondary Flow and the concertedness (velocity attitude and thermograde direction) in velocity field and temperature field, realizes enhanced heat exchange.The generation of described fin adopts processing method for stamping.Described zoning turbulence model is standard k-ε model.Described tab construction is triangle or rectangular configuration.Described angle of attack size adjusts according to resistance situation in good time.
Part metals forms the triangle or rectangular configuration (fin) upwards dug to adopt process for stamping to make that fin (carrys out flow path direction), and this structure and fin surface are in 90 ° of angles, and the angle of attack can adjust according to resistance situation in good time.
To flow outward and heat-transfer character is studied to the extended surface tube after optimizing based on CFD method for numerical simulation, concrete numerical computations step is as follows:
A, first in Gambit software
A1) set up economizer local geometry model, calculate the fluid mass of selected built-in two groups of fins;
A2) grid is created, selected tetrahedral grid in calculating;
A3) boundary types is set, comprises fluid mass, entrance, outlet, wall etc.;
A4) grid file is exported.
B, secondly in Fluent software
B1) read in grid file, check grid and define the information such as long measure;
B2) setting coupling, Implicit Method device, setting energy equation, established standards k-ε model;
B3) material properties of fluid is set;
B4) initial and boundary condition is set, comprise zoning entrance and adopt VELOCITY_INLET boundary condition (fluid v=5m/s, T=800K), the outlet of described zoning adopts OUTFLOW boundary condition, described zoning wall is without sliding velocity boundary condition, and described zoning near wall adopts the process of Standard law of wall method; Center extended surface tube is set as permanent wall temperature boundary condition, the wall surface temperature 420K of described extended surface tube;
5) set discrete and method for solving, comprise zoning pressure and select STANDARD form, SIMPLEC algorithm is selected in the coupling of calculating pressure speed, and the equation of momentum and energy equation all select Second-order Up-wind form;
6) start to solve and obtain result of calculation.
Fig. 1 is the numerical computations physical model of fin section.
Fig. 2, Fig. 3 are heat-transfer character and the drag characteristic comparison diagram of straight fin and different angle of attack fin.In order to better find out difference between the two, in figure, the heat transfer of straight fin and resistance coefficient are set as 1.Can find out in figure, fin come flow path direction stamp out the heat transfer property of tab construction will significantly better than common straight fin, wherein, the outer Nu number of extended surface tube pipe under ° operating mode of angle of attack β=30, can be made to improve 12.05%.Possible reason for when fluid is horizontal plunder barrier time, often produce vortex at the back side of barrier, the strong movements of these longitudinal vortexs, facilitate near heat transfer wall and main flow area fluid between momentum and the exchange of energy, strong flow perturbation plays the effect weakening or destroy boundary layer, thus heat transfer is strengthened.Compare the different angle of attack can find out, within the scope of discussion, the heat transfer property (Nu number) of three angles of attack is roughly the same, and wherein, 60 ° of angles of attack are slightly good, and 30 ° of angles of attack are slightly weak, and 45 ° of angles of attack are placed in the middle.Meanwhile, as shown in Figure 3, along with the increase of the angle of attack, the resistance through extended surface tube obviously increases.
In order to probe into the different angle of attack, the general PEC(PerformanceEvaluationCriteria in international heat transfer circle is introduced on the impact optimizing rear economizer complex heat transfer performance) criterion.This criterion has taken into full account the size of transferring heat under identical transmission power, when this value is greater than 1, illustrates that the heat transfer property of extended surface tube after secondary hardening is than good before strengthening; And when this value is less than 1, result is just in time contrary.
PEC calculating formula is PEC=(Nu/Nu
0)/(f/f
0)
1/3(2)
As shown in Figure 4, the PEC value of three angles of attack is all greater than 1, and this illustrates that this series is optimized structure and is conducive to improving the heat transfer property of heat transfer element, is conducive to realizing augmentation of heat transfer.Wherein, the PEC value of 30 ° of angles of attack is the highest, and combination property is best.
As shown in Figure 5,6, for optimizing the Y-direction velocity field contrast distribution figure of rear (with fin) extended surface tube and straight extended surface tube.Can find out in comparison diagram, after optimizing, flow field, extended surface tube fin rear portion produces eddy current in various degree, the momentum and energy that this eddy current makes main flow area fluid have component velocity perpendicular to main flow direction, this component velocity to accelerate fluid and main flow area fluid near heat transfer wall exchanges.Meanwhile, the generation of Secondary Flow changes velocity field distribution in heat transfer region, improves the concertedness between itself and temperature gradient field, effectively improves the heat transfer property of heat transfer element.
As shown in Figure 7,8, for optimizing the temperature field contrast distribution figure of rear (with fin) extended surface tube and straight extended surface tube.Comparison diagram can be found out, under identical primary condition, thin with fin extended surface tube more straight fin boundary layer, and thermograde is large, and these 2 all can prove with fin extended surface tube heat transfer property better.And fluid is obviously lower through the outlet temperature with fin extended surface tube, illustrates that the heat exchange amount of fin and fluid is larger, provide the evidence that after optimizing, extended surface tube heat transfer property improves from another point of view.
For verifying the heat transfer characteristic optimizing rear (with fin) extended surface tube and straight extended surface tube further, choose certain power plant #3 unit relevant device to test, wherein, test adopts heat transfer element for optimizing rear extended surface tube (fin angle of attack β=30 °) and straight extended surface tube two kinds.In test, extended surface tube in-line arrangement is arranged in boiler back end ductwork, and in it, external heat transfer medium is respectively flue gas and power plant chemistry demineralized water after boiler combustion, and flue gas is transversal flow extended surface tube in passage, and water is at fin Bottomhole pressure, and flue gas becomes counter-flow arrangement with water.
Need the parametric variable measured to have 7 in test, be respectively experimental rig import and export water temperature t
1, t
2, flow through the flue gas import and export temperature g of device
1, g
2, flow through the discharge G of device, the dynamic pressure P of device exiting flue gas and restrain upper and lower differential static pressure Δ P.Wherein, in test, the import and export temperature of water adopts thermometer measure, discharge adopts integrating flowmeter to measure, flue-gas temperature adopts K type armoured thermocouple points of engagement temperature measurement amount, the dynamic pressure of device exiting flue gas and flue gas differential pressure adopt Pitot tube, electronic micro-manometer to measure, and measuring point is arranged according to uiform section gridding method.
By import cigarette temperature g
1, outlet cigarette temperature g
2, inlet water temperature t
1, outlet water temperature t
2, can obtain
Δt
max=g
1-t
2Δt
min=g
2-t
1
Logarithmic mean temperature difference (LMTD) Δ t=(Δ t
max-Δ t
min)/In(Δ t
max/ Δ t
min) (3)
For the outer flue gas that circulates of pipe, the tube bank of circulation water in pipe, by water side draught heat formula Q=C
pg(t
2-t
1) and tube bank total heat transfer formula Q=KF Δ t can calculate
Overall heat-transfer coefficient K=C
pg(t
2-t
1)/F Δ t(4)
In formula, C
pfor the specific heat at constant pressure of water; G is the discharge flowing through tube bank in the unit time; t
1, t
2be respectively the import and export water temperature of tube bank; F is heat transfer area, gets finned tube geometry total surface area.
1/K=1/h
o+δ/λ+1/h
i(5)
In formula, δ is pipe thickness; λ is tube wall heat conduction coefficient; h
i, h
obe respectively the surface coefficient of heat transfer of water side and fume side.
Nu=0.023Re
0.8Pr
0.4(6)
h
i=Nuλ/d(7)
In formula, Nu is water side nusselt number; λ is the thermal conductivity factor of water; D is pipe diameter;
Re, Pr are respectively Reynolds number and the Prandtl number of water, and can be calculated by Re=ud/v, Pr=v/a and try to achieve, in formula, u is fluid velocity; V is fluid kinematic viscosity; A is thermal diffusion coefficient.
The comprehensive h that can try to achieve fume side with above formula (4) (5) (6) (7)
oand Nu.
Fig. 9,10 is respectively straight fin and β=30 ° angle of attack fin conducts heat and drag characteristic comparison of test results figure under different velocity in pipes (0.5m/s, 1.0m/s, 1.5m/s) operating mode.In like manner, in figure, the heat transfer of fin straight under same parameter operating mode and resistance coefficient are set as 1.Can find out, under three kinds of operating modes, a β=30 ° angle of attack fin heat-transfer character value is all greater than 1, and illustrate that this fin will obviously be better than straight fin on heat transfer property, Nu number average is higher than straight fin 12.59%.Meanwhile, the drag characteristic of β=30 ° angle of attack fin also will apparently higher than straight fin, and these result of the tests and numerical simulation result are substantially identical.
After compbined test and numerical simulation result can draw and optimize, the more existing straight extended surface tube of extended surface tube of (with fin) all has obvious change in all many-sides such as flow field, temperature, and these change the heat exchange property that effectively improve heat transfer element.
By reference to the accompanying drawings the specific embodiment of the present invention is described although above-mentioned; but not limiting the scope of the invention; one of ordinary skill in the art should be understood that; on the basis of technical scheme of the present invention, those skilled in the art do not need to pay various amendment or distortion that creative work can make still within protection scope of the present invention.
Claims (5)
1., based on a heat exchange property detection method for the H type economizer of longitudinal Vortex, it is characterized in that:
Described H type economizer comprises several and is arranged in order H type fin, the equal vertical welding of described H type fin is on extended surface tube, the part metals carrying out flow path direction of each described H type fin forms some fins upwards dug, described fin and H type fin surface are carried out flow path direction and are formed the angle of attack, a series of longitudinal Vortex can be produced when making fluid flow through extended surface tube passage, under the effect of longitudinal Vortex, fluid has had the component velocity perpendicular to main flow direction, this component velocity accelerates mixing of main flow area and fluid near the heat transfer wall of H type fin, promote fluid and the momentum of body region fluid and the exchange of energy near H type fin heat transfer wall, make boundary layer thinning or destroyed, reduce heat transfer resistance, improve convective heat-transfer coefficient, the angle of the described angle of attack is 30 °, the fin number of each described H type fin is 2-4,
Extended surface tube in-line arrangement is arranged in boiler back end ductwork, and in it, external heat transfer medium is respectively flue gas and power plant chemistry demineralized water after boiler combustion, and flue gas is transversal flow extended surface tube in passage, and water is at fin Bottomhole pressure, and flue gas becomes counter-flow arrangement with water;
The parametric variable measured has 7, is respectively experimental rig import and export water temperature t
1, t
2, flow through the flue gas import and export temperature g of device
1, g
2flow through the discharge G of device, the dynamic pressure P of device exiting flue gas and restrain upper and lower differential static pressure Δ P, wherein, in test, the import and export temperature of water adopts thermometer measure, and discharge adopts integrating flowmeter to measure, flue-gas temperature adopts K type armoured thermocouple points of engagement temperature measurement amount, the dynamic pressure of device exiting flue gas and flue gas differential pressure adopt Pitot tube, electronic micro-manometer to measure, and measuring point is arranged according to uiform section gridding method, introduce economizer complex heat transfer performance evaluation norm number PEC;
Its calculating formula is PEC=(Nu/Nu
0)/(f/f
0)
1/3(2)
By import cigarette temperature g
1, outlet cigarette temperature g
2, inlet water temperature t
1, outlet water temperature t
2, can obtain
Δt
max=g
1-t
2Δt
min=g
2-t
1
Logarithmic mean temperature difference (LMTD) Δ t=(Δ t
max-Δ t
min)/In (Δ t
max/ Δ t
min) (3)
For the outer flue gas that circulates of pipe, the tube bank of circulation water in pipe, by water side draught heat formula Q=C
pg (t
2-t
1) and tube bank total heat transfer formula Q=KF Δ t can calculate
Overall heat-transfer coefficient K=C
pg (t
2-t
1)/F Δ t (4)
In formula, C
pfor the specific heat at constant pressure of water; G is the discharge flowing through tube bank in the unit time; t
1, t
2be respectively the import and export water temperature of tube bank; F is heat transfer area, gets finned tube geometry total surface area;
1/K=1/h
o+δ/λ+1/h
i(5)
In formula, δ is pipe thickness; λ is tube wall heat conduction coefficient; h
i, h
obe respectively the surface coefficient of heat transfer of water side and fume side;
Nu=0.023Re
0.8Pr
0.4(6)
h
i=Nuλ/d(7)
In formula, Nu is water side nusselt number; λ is the thermal conductivity factor of water; D is pipe diameter;
Re, Pr are respectively Reynolds number and the Prandtl number of water, and can be calculated by Re=ud/v, Pr=v/a and try to achieve, in formula, u is fluid velocity; V is fluid kinematic viscosity; A is thermal diffusion coefficient;
The comprehensive h that can try to achieve fume side with above formula (2)-(7)
o, Nu and PEC.
2. the method for claim 1, is characterized in that, at least 2 described fins are distributed in the upper left corner and the upper right corner of H type fin respectively.
3. the method for claim 1, is characterized in that, at least 2 described fins are distributed in the upper left corner and the lower right corner of H type fin respectively.
4. the method for claim 1, is characterized in that, at least 2 described fins are distributed in the lower left corner and the upper right corner of H type fin respectively.
5. the method for claim 1, is characterized in that, at least 2 described fins are distributed in the lower left corner and the lower right corner of H type fin respectively.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201310545617.7A CN103557513B (en) | 2013-11-05 | 2013-11-05 | A kind of H type economizer based on longitudinal Vortex |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201310545617.7A CN103557513B (en) | 2013-11-05 | 2013-11-05 | A kind of H type economizer based on longitudinal Vortex |
Publications (2)
Publication Number | Publication Date |
---|---|
CN103557513A CN103557513A (en) | 2014-02-05 |
CN103557513B true CN103557513B (en) | 2016-03-09 |
Family
ID=50011831
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201310545617.7A Expired - Fee Related CN103557513B (en) | 2013-11-05 | 2013-11-05 | A kind of H type economizer based on longitudinal Vortex |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN103557513B (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105547031A (en) * | 2016-02-01 | 2016-05-04 | 西安交通大学 | Spiral and circular finned tube with longitudinal grooves |
CN106871696A (en) * | 2017-01-25 | 2017-06-20 | 东南大学 | The segmented fin of heat exchanger tube |
CN106840371B (en) * | 2017-03-07 | 2019-09-03 | 华电重工股份有限公司 | The acquisition methods of operatic tunes sound transmission loss in waste heat boiler furnace |
CN106874618B (en) * | 2017-03-07 | 2019-12-13 | 华电重工股份有限公司 | resistance obtaining method for finned tube array of waste heat boiler |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN2548107Y (en) * | 2002-06-08 | 2003-04-30 | 东方锅炉厂无锡热管分厂 | H-type finned tube |
CN101245974A (en) * | 2008-02-26 | 2008-08-20 | 西安交通大学 | Finned heat exchanger |
CN202733872U (en) * | 2012-07-19 | 2013-02-13 | 张家港华东锅炉有限公司 | Abrasion-proof tile used in H-type fins economizer |
CN103438746A (en) * | 2013-08-14 | 2013-12-11 | 西安交通大学 | Elliptical tube H-shaped fin heat exchanger for waste heat recovery |
-
2013
- 2013-11-05 CN CN201310545617.7A patent/CN103557513B/en not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN2548107Y (en) * | 2002-06-08 | 2003-04-30 | 东方锅炉厂无锡热管分厂 | H-type finned tube |
CN101245974A (en) * | 2008-02-26 | 2008-08-20 | 西安交通大学 | Finned heat exchanger |
CN202733872U (en) * | 2012-07-19 | 2013-02-13 | 张家港华东锅炉有限公司 | Abrasion-proof tile used in H-type fins economizer |
CN103438746A (en) * | 2013-08-14 | 2013-12-11 | 西安交通大学 | Elliptical tube H-shaped fin heat exchanger for waste heat recovery |
Also Published As
Publication number | Publication date |
---|---|
CN103557513A (en) | 2014-02-05 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Song et al. | Effect of geometric size of curved delta winglet vortex generators and tube pitch on heat transfer characteristics of fin-tube heat exchanger | |
Afshari et al. | Effect of turbulator modifications on the thermal performance of cost-effective alternative solar air heater | |
Bhuiyan et al. | Thermal and hydraulic performance of finned-tube heat exchangers under different flow ranges: A review on modeling and experiment | |
Lotfi et al. | 3D numerical investigation of flow and heat transfer characteristics in smooth wavy fin-and-elliptical tube heat exchangers using new type vortex generators | |
Tahseen et al. | An overview on thermal and fluid flow characteristics in a plain plate finned and un-finned tube banks heat exchanger | |
Wang et al. | Recent development and application of several high-efficiency surface heat exchangers for energy conversion and utilization | |
Jiang et al. | Heat transfer performance enhancement of liquid cold plate based on mini V-shaped rib for battery thermal management | |
Vaisi et al. | Experimental investigation of geometry effects on the performance of a compact louvered heat exchanger | |
Wang et al. | An investigation of influence factor including different tube bundles on inclined elliptical fin-tube heat exchanger | |
Khoshvaght-Aliabadi et al. | Al2O3–water nanofluid inside wavy mini-channel with different cross-sections | |
He et al. | Convective heat transfer enhancement: Mechanisms, techniques, and performance evaluation | |
CN103557513B (en) | A kind of H type economizer based on longitudinal Vortex | |
Ahmed et al. | Experimental study of heat transfer augmentation in non-circular duct using combined nanofluids and vortex generator | |
Ding et al. | An adaptive flow path regenerator used in supercritical carbon dioxide Brayton cycle | |
Dang et al. | The performances of circular tube bank fin heat exchangers with fins punched with quadrilateral vortex generators and flow re-distributors | |
Nabilah et al. | Numerical simulation of heat transfer enhancement from tubes surface to airflow using concave delta winglet vortex generators | |
Nia et al. | Numerical simulation of air heating by the recovered waste heat from the radiating exhaust gas flows in a plate heat exchanger | |
Ranjan et al. | Hydro-thermal characteristics of laminar flow through a square duct having transverse ribs and helical screw-tape inserts | |
Ahmadi | Influences of optimizing the turbulator arrangement on the heat transfer and hydraulic characteristics of the tubular heat exchanger | |
Heriyani et al. | Perforated concave rectangular winglet pair vortex generators enhance the heat transfer of air flowing through heated tubes inside a channel | |
Zhang et al. | A comparative evaluation of double-pipe heat exchangers with enhanced mixing | |
Ali et al. | Evaluation of shell and tube heat exchanger performance by using ZnO/water nanofluids | |
Thantharate et al. | Experimental and numerical comparison of heat transfer performance of twisted tube and plain tube heat exchangers | |
Sunden | Simulation of compact heat exchanger performance | |
Ai et al. | Numerical simulation on JAG-type corrugated plate flow heat transfer characteristics considering physical property changes and shell heat transfer |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
CF01 | Termination of patent right due to non-payment of annual fee | ||
CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20160309 Termination date: 20201105 |