EP4283137A1 - Zentrifugalpumpe - Google Patents

Zentrifugalpumpe Download PDF

Info

Publication number
EP4283137A1
EP4283137A1 EP22175498.9A EP22175498A EP4283137A1 EP 4283137 A1 EP4283137 A1 EP 4283137A1 EP 22175498 A EP22175498 A EP 22175498A EP 4283137 A1 EP4283137 A1 EP 4283137A1
Authority
EP
European Patent Office
Prior art keywords
grooves
centrifugal pump
front shroud
impeller
pump
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.)
Pending
Application number
EP22175498.9A
Other languages
English (en)
French (fr)
Inventor
Michael Mansour
Dominique Thevenin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Otto Von Guericke Universitaet Magdeburg
Original Assignee
Otto Von Guericke Universitaet Magdeburg
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Otto Von Guericke Universitaet Magdeburg filed Critical Otto Von Guericke Universitaet Magdeburg
Priority to EP22175498.9A priority Critical patent/EP4283137A1/de
Publication of EP4283137A1 publication Critical patent/EP4283137A1/de
Pending legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D31/00—Pumping liquids and elastic fluids at the same time
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D1/00—Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/08—Sealings
    • F04D29/16—Sealings between pressure and suction sides
    • F04D29/161—Sealings between pressure and suction sides especially adapted for elastic fluid pumps
    • F04D29/162—Sealings between pressure and suction sides especially adapted for elastic fluid pumps of a centrifugal flow wheel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/18—Rotors
    • F04D29/22—Rotors specially for centrifugal pumps
    • F04D29/2261—Rotors specially for centrifugal pumps with special measures
    • F04D29/2288—Rotors specially for centrifugal pumps with special measures for comminuting, mixing or separating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
    • F04D29/426—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for liquid pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
    • F04D29/44—Fluid-guiding means, e.g. diffusers
    • F04D29/445—Fluid-guiding means, e.g. diffusers especially adapted for liquid pumps

Definitions

  • the present invention relates to centrifugal pumps with semi-open impeller for transporting gas-liquid two-phase flows.
  • the present invention relates to a design for centrifugal pumps with increased transport delivery capacity for gas-liquid two-phase flows.
  • centrifugal pumps comprise a casing, typically having a volute form surrounding the impeller said impeller comprising a back plate onto which is mounted a number of blades, with a free space between adjacent blades, said free space being referred to "channel".
  • a front shroud is arranged above the blades at a defined distance, the tip clearance gap or, simply, gap.
  • the tip clearance gap between impeller and front shroud such impeller arrangement is known as semi-open impeller with standard gap and semi-open impeller with increased gap, respectively.
  • Centrifugal pumps are well known devices for energy conversion where rotational energy of an impeller is transferred to the fluid that is to be transported.
  • DE 35 44 566 A1 describes impellers for a semiradial or “mixed flow” type pump comprising openings in the back plate within the channels formed by adjacent blades for allowing the recirculation of the gaseous and liquid phases in order to ensure their mixing and avoiding accumulation of the gas.
  • this object is solved by a centrifugal pump with semi-open impeller, wherein macroscopic grooves are provided to the surface of the front shroud directed towards the impeller blades.
  • the macroscopic grooves of the present invention are characterized by having dimensions such as depth and width in the order of millimeter.
  • the mixing effect of the secondary flow in the tip clearance gap across the impeller blades is maximized by creating intensified vortices, thereby delaying and reducing gas accumulation. In particular, good results can be obtained even at high gas content.
  • the alignment of the grooves on the surface of the front shroud can be circumferential, radial, combinations of both of them, such as curved with radial and circumferential components, or any other configuration.
  • the cross-section profile can be selected from rectangular, semi-circular, rectangular with curved corners, etc.
  • the parameters defining the design of the macroscopic grooves of present invention include number of grooves, alignment, dimensions of grooves, cross-section profile, the inter-groove distance, and in case of radial grooves the length. It is understood that these parameters can vary depending on the particular configuration of the pump, working condition etc.
  • At least one of the width, depth and radius, respectively is in the order of millimeter (mm), preferably width, depth and radius, respectively, are all in the order of millimeter (mm).
  • the depth can be selected from 2 mm to 12 mm, preferably 3 mm to 10 mm, the width from 6 mm to 12 mm, preferably from 8 to 10 mm and the radius from 1 to 5 mm, respectively.
  • the number of grooves is not particularly restricted, but can be selected according to need depending on the circumstances, such as design of pump and size of front shroud.
  • a typical number of grooves ranges from 3 to 20, preferably 5 to 16.
  • the length of the radial grooves is not particularly restricted.
  • the radial grooves extend radially across the surface of the shroud.
  • the length of the radial grooves can be less than the width of the front shroud, i.e. the distance between the inner and outer diameter of the front shroud.
  • the radial grooves can start at a distance from the inner circumference and end at a distance from the outer circumference of the front shroud.
  • the grooves in the front shroud increase the turbulence of the flow and mixing of the phases with development of strong secondary flow and many vortices, thereby avoiding or at least delaying gas accumulation and phase segregation.
  • the outer diameter and total area, respectively, of the front shroud can vary according to need, for example depending on the design of the impeller and blades. Typically the outer diameter can range from 100 mm to 500 mm.
  • the number of grooves can be adapted to the respective outer diameter.
  • a larger area of the front shroud can require a larger number of grooves.
  • FIG. 1 the structure of a typical centrifugal pump 1 with semi-open impeller 2 is shown with a representation of individual components in an exploded view.
  • the impeller 2 has a back plate 3 onto which a number of diverging curved blades 4 is arranged. Above the blades 4 a front shroud 5, 7, 9 is provided at a defined distance forming a gap.
  • a front shroud 9 of prior art a front shroud 9 with radial grooves 6, and one 7 with circumferential grooves 8, respectively, according to the present invention with the grooves 6, 8 being provided on the surface of the front shroud 5, 7 facing the blades 4.
  • Impeller 2 and inducer 10 are mounted on the same shaft (not shown).
  • the pump 1 has a volute casing 11 for housing the impeller 2 with pressure outlet 12 and inlet pipe 13 with mass flow inlet 14.
  • the mass flow inlet 14 is divided into circular air inlet 15 located in the center and an annular water inlet 16 surrounding the circular air inlet 15.
  • the impeller shown in Figures 2a and 2b is equipped with 6 non-twisted blades, while the inducer has 3 helical blades to provide low inlet solidity as described in Gülich, J.F., 2008, Centrifugal Pumps, Springer , with a detailed description of design procedures for pumps.
  • Impeller Geometrical Dimensions Parameter Symbol Impeller blade inlet diameter D 1 Impeller blade outlet diameter D 2 Impeller blade inlet width b 1 Impeller blade outlet width b 2 Suction pipe diameter Ds Inducer hub to tip diameter ratio D h /D t Inducer blade axial length L b /D s Tip clearance gap (gap) S Radial tip clearance gap of inducer S i width of tip clearance gap S/b 2 width of inducer tip clearance gap S i /b 2
  • FIG 3a a sample design of a front shroud 7 with circumferential grooves 8 is shown as top view and as section through line A - A of the top view.
  • five circumferential grooves 8 are provided in coaxial manner on the front shroud 5, the circumferential grooves 8 having a rectangular cross-section profile as shown in the section view with W indicating the width and D the depth of each groove 8.
  • FIG. 3b A sample design of a front shroud 5 with radial grooves 6 is shown in Figure 3b as top view and as section through line A-A of the top view.
  • a number of sixteen radial grooves 6 is regularly distributed over the surface of the front shroud 5 and extends radially outward.
  • the width of the grooves 6 increases with increasing diameter of the front shroud 5 where the referenced width being the width at mid-length of the radial grooves 6 resulting in a symmetrical trapezoid form. That is, here reference to width of the radial grooves relates to width at mid-length of the respective groove.
  • the cross-section profile of the radial and circumferential grooves 6, 8 is rectangular.
  • Figures 4a to 4d Some examples for different designs of the grooves for the front shroud according to the present invention are shown in Figures 4a to 4d as a section view through impeller 2 with back plate 3, blade 4, and front shroud with grooves.
  • Figure 4a Shown in Figure 4a are circumferential grooves with rectangular cross-section profile with W being width and D being depth, Figure 4b circumferential grooves with semi-circular cross-section profile with r being the radius, Figure 4c circumferential grooves with rectangular cross-section profile and curved corners, and Figure 4d a front shroud with radial grooves with L being the length of the grooves and D being the depth.
  • the pumps according to the present invention had a semi-open impeller with standard gap with the front shroud being provided with either radial or circumferential grooves.
  • the setting for the impeller were the same as used for the prior art pump with standard gap as set out in Table 2 with reference to Figures 2a and 2b .
  • the parameters changed in case of radial grooves were depth (D), width (W), and number of grooves (n g ) with the radial grooves stretching radially along the shroud.
  • the length of the radial grooves was always constant and shorter than the blade radial length.
  • Table 3 the details of all grooves combination according to this invention used in the examples are listed.
  • Table 3 Parameter of grooves Groove type Groove name Groove crosssection No. of grooves Width (mm) W Depth (mm) D Radius (mm) r Length (mm) L Circumferential grooves C1 Rectangular 5 10 5 0 - C2 3 C3 8 8 C4 3 10 5 C5 Semicircular 3 0 0 5 Radial grooves R1 Rectangular 16 10 10 0 71 R2 8 R3 5 R4 8 10 R5 12 10 5
  • the gas volume fraction ⁇ was set to 3 %.
  • the results obtained for this setting of the gas volume fraction can be representative for higher gas volume fractions as has been shown in previous studies [1,2]. These studies show that a pump keeps its performance for higher gas volume fraction as found by a similar analysis concerning turbulence and mixing.
  • the surface uniformity S u also called uniformity index
  • S u also called uniformity index
  • the value S u always ranges from S u , min and 1, with the minimum value being found at the inlet surface where the two phases are completely separated at injection.
  • the non-dimensional mixing coefficient M c ranges between 0 and 1, where 0 indicates no mixing at all (gas and liquid are perfectly separated like in the injection plane of the inlet surface), while 1 indicates that the two phases are perfectly mixed.
  • the pumps with grooved front shrouds of the present invention results in smaller and more dispersed gas bubbles compared to those of the prior art pumps.
  • the radial grooves show an even higher number of smaller structures compared to the circumferential grooves particularly for nominal and overload conditions.
  • the presence of the grooves results in formation of strong secondary flows with many vortices for both the circumferential and the radial grooves.
  • the impeller blades move past the grooves, the vortices were stretched along the blades and the recirculation zones were fed continuously by the impeller rotation, which amplifies the mixing of the gas and the liquid. Higher turbulence and mixing levels are obtained which significantly support two-phase pumping, particularly at high gas volume fractions.
  • the pumps with circumferential groves according to the present invention have improved flow mixing at part-load compared to the prior art pumps without inducer, yet less than the pump with inducer.
  • all the examples of pumps with radial grooves according to the present invention are clearly better than all other configurations inclusive the prior art pump with inducer, leading to a strong improvement in two-phase mixing.
  • the examples with radial grooves according to the present invention show at least as good results than the best prior art pump, i.e. the pump with inducer, with example R1 being much better than the prior art pump with inducer.
  • the performance of the examples with radial grooves according to the present invention is significantly better than both that of the examples with circumferential grooves according to the present invention and the prior art pump with standard gap exceed the performance of the prior art pump with inducer, with R1 exceeding all the other pumps studied.
  • pump R1 has the highest number of grooves, 16, and largest cross-section area. Consequently, it is believed that there is a positive correlation between the total area of the radial grooves and the resulting efficiency.
  • the total area of the radial grooves A G is calculated by multiplying the number of grooves by the width and the depth.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
EP22175498.9A 2022-05-25 2022-05-25 Zentrifugalpumpe Pending EP4283137A1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP22175498.9A EP4283137A1 (de) 2022-05-25 2022-05-25 Zentrifugalpumpe

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP22175498.9A EP4283137A1 (de) 2022-05-25 2022-05-25 Zentrifugalpumpe

Publications (1)

Publication Number Publication Date
EP4283137A1 true EP4283137A1 (de) 2023-11-29

Family

ID=81850124

Family Applications (1)

Application Number Title Priority Date Filing Date
EP22175498.9A Pending EP4283137A1 (de) 2022-05-25 2022-05-25 Zentrifugalpumpe

Country Status (1)

Country Link
EP (1) EP4283137A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117627955A (zh) * 2023-12-05 2024-03-01 吉林大学 一种防破乳的胶乳泵叶轮

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3544566A1 (de) 1984-12-22 1986-07-03 Rolls-Royce Ltd., London Laufrad fuer eine zentrifugalpumpe
JPH094585A (ja) * 1995-06-20 1997-01-07 Torishima Pump Mfg Co Ltd 汚水ポンプ
US20120051897A1 (en) * 2010-07-21 2012-03-01 Itt Manufacturing Enterprises, Inc. Wear Reduction Device for Rotary Solids Handling Equipment
US20170016457A1 (en) * 2014-06-24 2017-01-19 Concepts Nrec, Llc Flow Control Structures For Turbomachines and Methods of Designing The Same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3544566A1 (de) 1984-12-22 1986-07-03 Rolls-Royce Ltd., London Laufrad fuer eine zentrifugalpumpe
JPH094585A (ja) * 1995-06-20 1997-01-07 Torishima Pump Mfg Co Ltd 汚水ポンプ
US20120051897A1 (en) * 2010-07-21 2012-03-01 Itt Manufacturing Enterprises, Inc. Wear Reduction Device for Rotary Solids Handling Equipment
US20170016457A1 (en) * 2014-06-24 2017-01-19 Concepts Nrec, Llc Flow Control Structures For Turbomachines and Methods of Designing The Same

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
GULICH, J.F.: "Centrifugal pumps", 2008, SPRINGER
MANSOUR, M.PARIKH, T.ENGEL, S.WUNDERLICH, B.THEVENIN, D.: "Investigation on the influence of an inducer on the transport of single and two-phase air-flows by centrifugal pumps, in: 48thTurbomachinery & 35th Pump Symposia", 2019
MANSOUR, M.WUNDERLICH, B.THEVENIN, D.: "Effect of tip clearance gap and inducer on the transport of two-phase air-water flows by centrifugal pumps", EXP. THERM FLUID SCI., vol. 99, 2018, pages 487 - 509, XP085470945, DOI: 10.1016/j.expthermflusci.2018.08.018
PARIKH, T.MANSOUR, M.THEVENIN, D.: "Investigations on the effect of tip clearance gap and inducer on the transport of air-water two-phase flow by centrifugal pumps", CHEM. ENG. SCI., vol. 218, 2020, pages 115554, XP086135546, DOI: 10.1016/j.ces.2020.115554

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117627955A (zh) * 2023-12-05 2024-03-01 吉林大学 一种防破乳的胶乳泵叶轮

Similar Documents

Publication Publication Date Title
US6695579B2 (en) Diffuser having a variable blade height
KR960002023B1 (ko) 높은 효율 및 넓은 작동 범위를 갖는 원심 압축기
DE69506297T2 (de) Axialpumpen
EP1473465B2 (de) Verdichter
US6203275B1 (en) Centrifugal compressor and diffuser for centrifugal compressor
US5885058A (en) Multiphase fluid pumping or compression device with blades of tandem design
US8550771B2 (en) Inducer for centrifugal pump
DE1428191A1 (de) Kreiselgeblaese
EP0040534A1 (de) Kompressordiffusor
JP3393653B2 (ja) ポンプ輸送または多相圧縮装置とその用途
US9631622B2 (en) Inducer for centrifugal pump
EP2480793B1 (de) Rotodynamische maschine
EP4283137A1 (de) Zentrifugalpumpe
CN106089807A (zh) 一种基于分形叶片的扩压器
Bayomi et al. Effect of inlet straighteners on centrifugal fan performance
CN105041720A (zh) 一种高效大过流旋流泵准环形压水室水力设计方法
EP3009682B1 (de) Axialventilator mit aussen- und innendiffusor
CN106640742B (zh) 一种螺旋轴流式油气混输泵叶轮
Issac et al. Effect of diffuser vane height and position on the performance of a centrifugal compressor
Reddy et al. Effect of the setting angle of a low-solidity vaned diffuser on the performance of a centrifugal compressor stage
US20060120866A1 (en) Centrifugal impeller and pump apparatus
Chernobrova et al. Influence of different volute casings theoretical methods design on pump working processes
RU2692941C1 (ru) Рабочее колесо центробежного насоса для газожидкостных сред
US7399155B2 (en) Fluid flow guide element and fluid flow apparatus equipped therewith
US4453886A (en) Centrifugal venturi

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN PUBLISHED

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20240409

RBV Designated contracting states (corrected)

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR