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CN-121980984-A - Residual compression coefficient calculation method based on mixed lubrication model plunger pump flow distribution pair

CN121980984ACN 121980984 ACN121980984 ACN 121980984ACN-121980984-A

Abstract

The invention discloses a residual compression coefficient calculation method based on a mixed lubrication model plunger pump flow distribution pair, which comprises the following steps of S1, determining a calculation parameter, S2, determining an initial film thickness h in a film forming domain, and changing a liquid film bearing capacity P f by adjusting the film thickness h to ensure that a force system consisting of a static pressure P SC , the liquid film bearing capacity P f and a contact stress P c meets the radial pressure balance difference S3, calculating tangential critical stiffness K x of the microprotrusions, comparing tangential critical stiffness K x with maximum stiffness K 0 , carrying out mixed lubrication solution when the relation between the tangential critical stiffness K x and the maximum stiffness K 0 meets the slip condition of the microprotrusions to obtain leakage quantity Q 2 and friction force f, S4, calculating residual compression coefficient lambda of the rotor by considering the balance relation between the friction force f and the leakage quantity Q 2 , and judging volumetric efficiency If the preset requirement is met, returning to the step S1, adjusting the rotor parameters, and recalculating until the volumetric efficiency is achieved if the preset requirement is not met Meets the preset requirement, and the method is ended.

Inventors

  • YIN TUYUAN
  • WANG YUHAO
  • MIAO KEFEI
  • LIU HUIXIANG

Assignees

  • 北京精密机电控制设备研究所

Dates

Publication Date
20260505
Application Date
20251212

Claims (10)

  1. 1. The residual compression coefficient calculation method based on the mixed lubrication model plunger pump flow distribution pair is characterized by comprising the following steps of: s1, determining the structure of a flow distribution pair and calculation parameters in a contact domain; S2, in the film forming domain, firstly determining an initial film thickness h, and then changing the liquid film bearing capacity P f by adjusting the film thickness h to ensure that a force system consisting of the static pressure P SC , the liquid film bearing capacity P f and the contact stress P c meets the radial pressure balance difference , A preset threshold value; S3, calculating tangential critical stiffness K x of the microprotrusions, and carrying out mixed lubrication solution by comparing the tangential critical stiffness K x with maximum stiffness K 0 when the relation between the tangential critical stiffness K x and the maximum stiffness K 0 meets the slip condition of the microprotrusions, wherein the method comprises the following steps: Calculating leakage Q 2 generated by the liquid film gap layer according to the film thickness h obtained in the step S2; Calculating the liquid film bearing capacity P f and the contact stress P c obtained in the step S2 to obtain a friction force f; S4, calculating a residual compression coefficient lambda by considering the balance relation between the friction force f and the leakage quantity Q 2 , and judging the volumetric efficiency If the preset requirement is met, returning to the step S1, adjusting the rotor size, and recalculating until the volumetric efficiency is achieved if the preset requirement is not met Meets the preset requirement, and the method is ended.
  2. 2. The method for calculating the residual compression factor of the plunger pump flow distribution pair based on the mixed lubrication model according to claim 1, wherein in the step S2, the liquid film bearing capacity P f is calculated by a Reynolds equation of a polar coordinate, the contact stress P c is calculated by a contact stress formula, and the static pressure P SC is obtained by finite element analysis.
  3. 3. The method for calculating the residual compression coefficient of the plunger pump flow distribution pair based on the mixed lubrication model according to claim 1 is characterized in that in the step S3, the mixed lubrication solution is carried out when K x ≤0.851K 0 is carried out.
  4. 4. The method for calculating the residual compression factor of the plunger pump flow distribution pair based on the mixed lubrication model according to claim 1, wherein in the step S3, the calculation formula of the leakage quantity Q 2 is as follows: In the formula, In order to be at the working pressure, The dynamic viscosity is that R4 is the outer diameter of the sealing band, and R1 is the inner diameter of the sealing band; The friction force f is calculated as: In the formula, Obtained by integrating the liquid film bearing capacity P f , Obtained by integrating the contact stress P c .
  5. 5. The method for calculating the residual compression factor of the plunger pump flow distribution pair based on the mixed lubrication model according to claim 1, wherein in the step S4, the preset requirement of the volumetric efficiency is as follows: >90%。
  6. 6. Residual compression coefficient calculation system based on mixed lubrication model plunger pump is joined in marriage a class pair, its characterized in that includes: The first module is used for determining the structure of the flow distribution pair and the calculation parameters in the contact domain; A second module for determining an initial film thickness h in the film forming region, and changing the liquid film bearing capacity P f by adjusting the film thickness h to make the force system composed of the static pressure P SC , the liquid film bearing capacity P f and the contact stress P c satisfy the radial pressure balance difference , A preset threshold value; The third module is configured to calculate a tangential critical stiffness K x of the microprotrusions, and perform a mixed lubrication solution by comparing the tangential critical stiffness K x with a maximum stiffness K 0 when a relation between the tangential critical stiffness K x and the maximum stiffness K 0 satisfies a slip condition of the microprotrusions, where the mixed lubrication solution includes: Calculating leakage Q 2 generated by the liquid film gap layer according to the film thickness h obtained in the step S2; Calculating the liquid film bearing capacity P f and the contact stress P c obtained in the step S2 to obtain a friction force f; A fourth module for calculating a residual compression coefficient lambda in consideration of a balance relationship between the friction force f and the leakage quantity Q 2 , judging volumetric efficiency If the preset requirement is met, returning to the first module, adjusting the rotor size, and recalculating until the volumetric efficiency is achieved Meets the preset requirement, and the method is ended.
  7. 7. The system for calculating the residual compression factor of the plunger pump flow distribution pair based on the mixed lubrication model according to claim 6, wherein in the second module, the liquid film bearing capacity P f is calculated by a Reynolds equation of a polar coordinate, the contact stress P c is calculated by a contact stress formula, and the static pressure P SC is obtained by finite element analysis.
  8. 8. The residual compression factor computing system based on the mixed lubrication model plunger pump flow distribution pair of claim 6, wherein in the third module, the mixed lubrication solution is performed at the time of K x ≤0.851K 0 .
  9. 9. The residual compression factor computing system based on the mixed lubrication model plunger pump flow distribution pair of claim 6, wherein in the third module, the calculation formula of the leakage quantity Q 2 is: In the formula, In order to be at the working pressure, The dynamic viscosity is that R4 is the outer diameter of the sealing band, and R1 is the inner diameter of the sealing band; The friction force f is calculated as: In the formula, Obtained by integrating the liquid film bearing capacity P f , Obtained by integrating the contact stress P c .
  10. 10. The residual compression factor computing system based on the mixed lubrication model plunger pump flow distribution pair of claim 6, wherein in the fourth module, the volumetric efficiency preset requirement is: >90%。

Description

Residual compression coefficient calculation method based on mixed lubrication model plunger pump flow distribution pair Technical Field The invention relates to the field of hydraulic element design, in particular to a residual compression coefficient calculation method based on a mixed lubrication model plunger pump flow distribution pair. Background The axial swashplate plunger pump (abbreviated as a plunger pump) is a power element in a hydraulic system, and the long-term operation of a valve plate-rotor (a valve pair) of one of key friction pairs causes the abrasion and peeling of the surfaces of the friction pairs. The wear spalls off to form a tiny gap along which liquid flows out of the friction pair under pressure, resulting in an increase in leakage rate and a decrease in residual compaction factor. At present, the calculation research of the flow distribution pair lubrication is mature, but a elastohydrodynamic lubrication model is mainly adopted, a mixed lubrication model is rarely adopted, the residual compression coefficient parameters are ignored, and the influence of the residual compression coefficient on the leakage rate and friction balance cannot be considered. While the previous research also relates to the concept of the residual compression factor of the plunger pump, the basic formula is generally directly called, and the formula does not consider the mixed lubrication characteristic, lacks fusion with tribology theory, and does not consider the relation between the leakage rate and the abrasion. By researching the residual compression coefficient of the plunger pump under the low-pressure working condition, a spring flow lubrication model of the flow distribution pair can be established, because a contact area does not exist. However, the high pressure condition requires the establishment of a hybrid lubrication model because it carries the main contact stresses, and the residual compaction factor is related to the contact stresses. Therefore, a method for calculating the residual compression coefficient of the plunger pump flow distribution pair based on the mixed lubrication model is needed to be provided on the basis of the prior art. Disclosure of Invention The invention solves the technical problems of overcoming the defects of the prior art, providing a residual compression coefficient calculation method based on a mixed lubrication model plunger pump flow distribution pair, better balancing leakage rate and friction physical quantity, optimizing the size of a rotor sealing belt and providing more reasonable residual compression coefficient. The technical scheme of the invention is to provide a residual compression coefficient calculation method based on a mixed lubrication model plunger pump flow distribution pair, which comprises the following steps: s1, determining the structure of a flow distribution pair and calculation parameters in a contact domain; S2, in the film forming domain, firstly determining an initial film thickness h, and then changing the liquid film bearing capacity P f by adjusting the film thickness h to ensure that a force system consisting of the static pressure P SC, the liquid film bearing capacity P f and the contact stress P c meets the radial pressure balance difference ,A preset threshold value; S3, calculating tangential critical stiffness K x of the microprotrusions, and carrying out mixed lubrication solution by comparing the tangential critical stiffness K x with maximum stiffness K 0 when the relation between the tangential critical stiffness K x and the maximum stiffness K 0 meets the slip condition of the microprotrusions, wherein the method comprises the following steps: Calculating leakage Q 2 generated by the liquid film gap layer according to the film thickness h obtained in the step S2; Calculating the liquid film bearing capacity P f and the contact stress P c obtained in the step S2 to obtain a friction force f; S4, calculating a residual compression coefficient lambda by considering the balance relation between the friction force f and the leakage quantity Q 2, and judging the volumetric efficiency If the preset requirement is met, returning to the step S1, adjusting the rotor size, and recalculating until the volumetric efficiency is achieved if the preset requirement is not metMeets the preset requirement, and the method is ended. Further, in step S2, the liquid film bearing capacity P f is calculated by Reynolds equation of polar coordinates, the contact stress P c is calculated by contact stress formula, and the static pressure P SC is obtained by finite element analysis. Further, in step S3, at K x≤0.851K0, a mixed lubrication solution is performed. Further, in step S3, the calculation formula of the leakage Q 2 is: In the formula, In order to be at the working pressure,The dynamic viscosity is that R4 is the outer diameter of the sealing band, and R1 is the inner diameter of the sealing band; The friction force f is calculated