Oil return ventilation system cavity pressure matching calculation method, device, equipment and medium

Abstract

The application discloses an oil return ventilation system cavity pressure matching calculation method, device, equipment and medium. Compared with a traditional calculation method, the oil return ventilation system cavity pressure matching calculation method considers two-phase flow conditions in an oil return system, performs relevant iterative calculation by establishing a cavity pressure calculation model, presetting bearing cavity pressure values and accessory transmission cavity pressure values, and obtains an oil return ventilation system cavity pressure matching calculation result after the error of the air valve ventilation mass flow difference and the accessory transmission cavity pressure value difference in the iterative calculation meets the set error requirement. The calculation result is more accurate and reliable than the traditional calculation method. Meanwhile, the application can be realized by a graph curve fitting method under the premise of computer calculation, and a special calculation program can not be written, so that the workload is reduced.

Description

Technical Field

[0001] This application relates to the field of aero-engine technology, and in particular to a method, apparatus, equipment and medium for calculating cavity pressure matching in an oil return ventilation system. Background Technology

[0002] Currently, aero gas turbine engines commonly employ closed-loop lubrication systems, typically consisting of oil supply, oil return, and ventilation subsystems (see...). Figure 1 The engine system comprises several subsystems. The oil supply subsystem primarily provides filtered and cooled pressurized lubricating oil to all lubrication points. The oil return subsystem draws lubricating oil from each return chamber and some leaked air from the bearing chambers back to the oil tank. The ventilation subsystem directs the oil and gas from each return chamber to the accessory drive housing, where it is then drained outside the engine after being cleaned by a ventilator. The ventilation subsystem regulates the pressure in each chamber, which determines the sealing characteristics of the main bearing housing and the performance of the oil return pump. Common ventilation subsystems typically use ventilation pipes to connect each chamber to the accessory drive housing, with the working medium generally being an oil-gas mixture dominated by gas. Unlike common ventilation subsystems, the oil return ventilation subsystem is highly coupled with the oil return subsystem. Bypasses and vent valves are installed on each return pipe to direct a portion of the oil-gas mixture to the accessory drive housing, where oil is the predominant phase.

[0003] For ventilation subsystems, common cavity pressure calculation methods treat the system formed by various ventilation ducts and ventilators as the object, perform flow path modeling, match ventilation volume, cavity pressure, and ventilator characteristics, and finally obtain the pressure value and ventilation volume of each cavity. However, the influence of the oil return subsystem on the ventilation subsystem is ignored in the calculation process. For oil return ventilation subsystems, due to their high coupling with the oil return subsystem, the influence of oil return on ventilation cannot be ignored. Therefore, traditional ventilation system cavity pressure calculations, which use simplified calculation methods that ignore the coupling effect of oil return ventilation and do not consider the two-phase flow condition of lubricating oil and air in the ventilation system, are not applicable to oil return ventilation systems. Summary of the Invention

[0004] This application provides a method for calculating cavity pressure matching in a return oil ventilation system to solve the technical problem that the existing technology, which uses a simplified calculation method that ignores the coupling effect of return oil ventilation and does not consider the two-phase flow condition of lubricating oil and air in the ventilation system, cannot be applied to return oil ventilation systems.

[0005] The technical solution adopted in this application is as follows: A method for calculating cavity pressure matching in an oil return ventilation system includes the following steps: S1. The working temperature, return oil temperature and cavity temperature of the sealing device inside the bearing cavity are obtained through bearing cavity thermal analysis. S2. Based on the sealing pressure, the leakage characteristics of the sealing device under different cavity pressures and operating temperatures of the sealing device need to be calculated; the mass flow rate characteristics of the air drawn by the return oil pump under different cavity pressures and return oil temperatures need to be calculated; the throttling characteristics of the vent valve orifice need to be calculated under different cavity pressures and return oil temperatures; the oil supply flow rate characteristics of the bearing cavity need to be calculated under different cavity pressures; the flow resistance characteristics of the ventilation pipe need to be calculated; and the flow resistance characteristics of the ventilator need to be calculated. S3. Establish a cavity pressure calculation model based on the above characteristics; S4. Preset a bearing cavity pressure value P. b1 ' Substituting into the cavity pressure calculation model, the total leakage flow W under the preset bearing cavity pressure value is obtained. s1 , corresponding bearing cavity pressure value, return oil air mass flow rate W p ; S5. Preset an accessory transmission chamber pressure value P. A1 ' According to the pressure value P of the accessory transmission cavity A1 ' Calculate the pressure difference before and after the throttle orifice to obtain the actual ventilation mass flow rate W through the vent valve under the corresponding pressure difference. v1 ; S6, based on the total leakage flow W s1 and return oil air mass flow rate W p The ventilation mass flow rate W of the vent valve was calculated. v2 ; S7, if W v1 and W v2 If the difference meets the error requirement, then the preset bearing cavity pressure value P will be set. b1 ' Pressure value P at the initial matching point b1 The total leakage flow rate W under the preset bearing cavity pressure value s1 This is the total leakage flow rate W at the initial matching pressure point. b1 Conversely, according to W v1 and W v2 The sign and magnitude of the difference are used to reset the bearing cavity pressure value P. b1 ' Perform iterative calculations until W is reached. v1 and W v2 The difference meets the error requirements; S8, W b1 Including the leakage gas flow rate W of other bearing cavities bn Obtain the total ventilation flow rate W t ; S9. Based on the total ventilation flow rate W t Obtain the pressure value P of the accessory transmission cavity. A1 ; S10. If the pressure value P of the accessory transmission cavity A1 The preset accessory transmission chamber pressure value P A1 ' If the difference meets the error requirement, the calculation ends; otherwise, the pressure value P of the accessory transmission cavity is preset again according to the sign and magnitude of the difference. A1 ' Then, the cavity pressure matching iteration calculation is performed again until the error requirement is met.

[0006] Furthermore, in step S4, the return air mass flow rate W is calculated under the corresponding bearing cavity pressure value. p During the process, considering the temperature and air density under the bearing cavity pressure, the volumetric flow rate of the return oil pump is converted into the mass flow rate.

[0007] Further, step S9 specifically includes: S91. Obtain the ventilation volume-cavity pressure characteristic curve of the accessory transmission cavity; S92, the total ventilation flow rate W t Substituting the airflow-pressure characteristic curve of the accessory transmission cavity, the pressure value P of the accessory transmission cavity is obtained. A1 .

[0008] This application also provides a cavity pressure matching calculation device for a return oil ventilation system, comprising: The bearing cavity thermal analysis module is used to obtain the working temperature, return oil temperature and cavity temperature of the sealing device inside the bearing cavity through bearing cavity thermal analysis. The characteristic calculation module is used to calculate the leakage characteristics of the sealing device under different cavity pressures and operating temperatures of the sealing device based on the sealing pressure; calculate the mass flow rate characteristics of the air drawn by the return oil pump under different cavity pressures and return oil temperatures; calculate the throttling characteristics of the vent valve orifice under different cavity pressures and return oil temperatures; calculate the oil supply flow rate characteristics of the bearing cavity under different cavity pressures; calculate the flow resistance characteristics of the ventilation pipe; and calculate the flow resistance characteristics of the ventilator. The cavity pressure calculation model establishment module is used to establish a cavity pressure calculation model based on the above characteristics; The module for calculating total leakage flow and return oil air mass flow is used to preset a bearing cavity pressure value P. b1 ' Substituting into the cavity pressure calculation model, the total leakage flow W under the preset bearing cavity pressure value is obtained. s1 , corresponding bearing cavity pressure value, return oil air mass flow rate W p ; The actual ventilation mass flow rate calculation module is used to preset an accessory transmission chamber pressure value P. A1 ' According to the pressure value P of the accessory transmission cavity A1 'Calculate the pressure difference before and after the throttle orifice to obtain the actual ventilation mass flow rate W through the vent valve under the corresponding pressure difference. v1 ; The ventilation mass flow calculation module for the vent valve is used to calculate the total leakage flow W. s1 and return oil air mass flow rate W p The ventilation mass flow rate W of the vent valve was calculated. v2 ; The ventilation valve ventilation mass flow error iterative calculation module is used for several W v1 and W v2 If the difference meets the error requirement, then the preset bearing cavity pressure value P will be set. b1 ' Pressure value P at the initial matching point b1 The total leakage flow rate W under the preset bearing cavity pressure value s1 This is the total leakage flow rate W at the initial matching pressure point. b1 Conversely, according to W v1 and W v2 The sign and magnitude of the difference are used to reset the bearing cavity pressure value P. b1 ' Perform iterative calculations until W is reached. v1 and W v2 The difference meets the error requirements; The total ventilation flow calculation module is used to calculate W. b1 Including the leakage gas flow rate W of other bearing cavities bn Obtain the total ventilation flow rate W t ; The accessory transmission cavity pressure value calculation module is used to calculate the total ventilation flow rate W. t Obtain the pressure value P of the accessory transmission cavity. A1 ; The accessory transmission cavity pressure value error iterative calculation module is used to calculate the pressure value P of the accessory transmission cavity. A1 The preset accessory transmission chamber pressure value P A1 ' If the difference meets the error requirement, the calculation ends; otherwise, the pressure value P of the accessory transmission cavity is preset again according to the sign and magnitude of the difference. A1 ' Then, the cavity pressure matching iteration calculation is performed again until the error requirement is met.

[0009] Furthermore, the total leakage flow rate and return air mass flow rate calculation module is also used to: calculate the return air mass flow rate W under the corresponding bearing cavity pressure value. p During the process, considering the temperature and air density under the bearing cavity pressure, the volumetric flow rate of the return oil pump is converted into the mass flow rate.

[0010] Furthermore, the accessory transmission cavity pressure value calculation module includes: The characteristic curve acquisition module is used to acquire the ventilation volume-cavity pressure characteristic curve of the accessory transmission cavity; The pressure value calculation module is used to calculate the total ventilation flow rate W. t Substituting the airflow-pressure characteristic curve of the accessory transmission cavity, the pressure value P of the accessory transmission cavity is obtained. A1 .

[0011] This application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the oil return ventilation system cavity pressure matching calculation method.

[0012] This application also provides a storage medium including a stored program that, when the program is executed, controls the device where the storage medium is located to perform the steps of the oil return ventilation system cavity pressure matching calculation method.

[0013] Compared with the prior art, this application has the following advantages: This application provides a method, apparatus, equipment, and medium for calculating cavity pressure matching in a return oil ventilation system. Compared with traditional calculation methods, the cavity pressure matching calculation method of this application considers the two-phase flow condition in the return oil ventilation system. It performs iterative calculations by establishing a cavity pressure calculation model, presetting bearing cavity pressure values ​​and accessory transmission cavity pressure values, and obtaining the cavity pressure matching calculation result after the error of the iterative calculation reaches a set error. This calculation result is more accurate and reliable than traditional calculation methods. Furthermore, provided that computer calculation is feasible, it can also be achieved through graph curve fitting methods, eliminating the need to write a dedicated calculation program and thus reducing workload.

[0014] In addition to the purposes, features, and advantages described above, this application has other purposes, features, and advantages. The application will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the closed-loop lubricating oil system of current aviation gas turbine engines; Figure 2 This is a schematic flowchart of the cavity pressure matching calculation method for the oil return ventilation system according to a preferred embodiment of this application; Figure 3 This is a flowchart illustrating a sub-step of step S9 in a preferred embodiment of this application; Figure 4This is a schematic diagram of the cavity pressure matching calculation device module of the oil return ventilation system according to a preferred embodiment of this application; Figure 5 This is a schematic diagram of a submodule of the attachment transmission cavity pressure value calculation module in a preferred embodiment of this application; Figure 6 This is a schematic block diagram of an electronic device according to a preferred embodiment of this application; Figure 7 This is a schematic diagram of the internal structure of a computer device according to a preferred embodiment of this application. Detailed Implementation

[0016] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0017] Reference Figure 2 A preferred embodiment of this application provides a method for calculating cavity pressure matching in an oil return ventilation system, including the following steps: S1. The working temperature, return oil temperature and cavity temperature of the sealing device inside the bearing cavity are obtained through bearing cavity thermal analysis. S2. Based on the sealing pressure, the leakage characteristics of the sealing device under different cavity pressures and operating temperatures of the sealing device need to be calculated; the mass flow rate characteristics of the air drawn by the return oil pump under different cavity pressures and return oil temperatures need to be calculated; the throttling characteristics of the vent valve orifice need to be calculated under different cavity pressures and return oil temperatures; the oil supply flow rate characteristics of the bearing cavity need to be calculated under different cavity pressures; the flow resistance characteristics of the ventilation pipe need to be calculated; and the flow resistance characteristics of the ventilator need to be calculated. S3. Establish a cavity pressure calculation model based on the above characteristics; S4. Preset a bearing cavity pressure value P. b1 ' Substituting into the cavity pressure calculation model, the total leakage flow W under the preset bearing cavity pressure value is obtained. s1 , corresponding bearing cavity pressure value, return oil air mass flow rate W p ; S5. Preset an accessory transmission chamber pressure value P. A1 ' According to the pressure value P of the accessory transmission cavity A1 ' Calculate the pressure difference before and after the throttle orifice to obtain the actual ventilation mass flow rate W through the vent valve under the corresponding pressure difference. v1 ; S6, based on the total leakage flow W s1 and return oil air mass flow rate W p The ventilation mass flow rate W of the vent valve was calculated. v2 ; S7, if W v1 and W v2If the difference meets the error requirement, then the preset bearing cavity pressure value P will be set. b1 ' Pressure value P at the initial matching point b1 The total leakage flow rate W under the preset bearing cavity pressure value s1 This is the total leakage flow rate W at the initial matching pressure point. b1 Conversely, according to W v1 and W v2 The sign and magnitude of the difference are used to reset the bearing cavity pressure value P. b1 ' Perform iterative calculations until W is reached. v1 and W v2 The difference meets the error requirements; S8, W b1 Including the leakage gas flow rate W of other bearing cavities bn Obtain the total ventilation flow rate W t ; S9. Based on the total ventilation flow rate W t Obtain the pressure value P of the accessory transmission cavity. A1 ; S10. If the pressure value P of the accessory transmission cavity A1 The preset accessory transmission chamber pressure value P A1 ' If the difference meets the error requirement, the calculation ends; otherwise, the pressure value P of the accessory transmission cavity is preset again according to the sign and magnitude of the difference. A1 ' Then, the cavity pressure matching iteration calculation is performed again until the error requirement is met.

[0018] Compared with the prior art, this embodiment has the following beneficial effects: This embodiment provides a method, apparatus, equipment, and medium for calculating cavity pressure matching in a return oil ventilation system. Compared with traditional calculation methods, the cavity pressure matching calculation method in this embodiment considers the two-phase flow condition in the return oil ventilation system. It performs iterative calculations by establishing a cavity pressure calculation model, presetting bearing cavity pressure values, and accessory transmission cavity pressure values. The cavity pressure matching calculation result is obtained after the error between the difference in ventilation mass flow rate of the ventilator and the difference in pressure value of the accessory transmission cavity in the iterative calculations meets the set error requirements. This calculation result is more accurate and reliable than traditional calculation methods. Furthermore, provided that computer calculation is feasible, it can also be achieved through graph curve fitting, eliminating the need to write a dedicated calculation program and thus reducing workload.

[0019] Specifically, in step S4, the return air mass flow rate W is calculated under the corresponding bearing cavity pressure value. pDuring the process, the influence of bearing cavity temperature and cavity pressure on air density was considered. The volumetric flow rate of the return oil pump was converted into mass flow rate to handle the two-phase flow condition of the return oil system. The air compression characteristics under various two-phase flow patterns were considered, and the two-phase flow characteristic problem of the lubricating oil pump was solved relatively accurately and simply. By converting it to the same mass flow rate unit as the bearing cavity sealing leakage gas, the problem of inconsistent units and inability to achieve joint calculation with the sealing device was solved.

[0020] Specifically, such as Figure 3 As shown, step S9 specifically includes: S91. Obtain the ventilation volume-cavity pressure characteristic curve of the accessory transmission cavity; S92, the total ventilation flow rate W t Substituting the airflow-pressure characteristic curve of the accessory transmission cavity, the pressure value P of the accessory transmission cavity is obtained. A1 .

[0021] In this embodiment, the ventilation volume-cavity pressure characteristic curve of the accessory transmission cavity is obtained through comprehensive ventilator and ventilation pipeline performance tests and simulations, possessing excellent objectivity and accuracy. Therefore, by using the total ventilation flow rate W... t Substituting the airflow-pressure characteristic curve of the accessory transmission cavity, an accurate and reliable pressure value P of the accessory transmission cavity can be obtained. A1 .

[0022] like Figure 4 As shown, this application also provides a cavity pressure matching calculation device for a return oil ventilation system, comprising: The bearing cavity thermal analysis module is used to obtain the working temperature, return oil temperature and cavity temperature of the sealing device inside the bearing cavity through bearing cavity thermal analysis. The characteristic calculation module is used to calculate the leakage characteristics of the sealing device under different cavity pressures and operating temperatures of the sealing device based on the sealing pressure; calculate the mass flow rate characteristics of the air drawn by the return oil pump under different cavity pressures and return oil temperatures; calculate the throttling characteristics of the vent valve orifice under different cavity pressures and return oil temperatures; calculate the oil supply flow rate characteristics of the bearing cavity under different cavity pressures; calculate the flow resistance characteristics of the ventilation pipe; and calculate the flow resistance characteristics of the ventilator. The cavity pressure calculation model establishment module is used to establish a cavity pressure calculation model based on the above characteristics; The module for calculating total leakage flow and return oil air mass flow is used to preset a bearing cavity pressure value P. b1 ' Substituting into the cavity pressure calculation model, the total leakage flow W under the preset bearing cavity pressure value is obtained. s1 , corresponding bearing cavity pressure value, return oil air mass flow rate W p ; The actual ventilation mass flow rate calculation module is used to preset an accessory transmission chamber pressure value P.A1 ' According to the pressure value P of the accessory transmission cavity A1 ' Calculate the pressure difference before and after the throttle orifice to obtain the actual ventilation mass flow rate W through the vent valve under the corresponding pressure difference. v1 ; The ventilation mass flow calculation module for the vent valve is used to calculate the total leakage flow W. s1 and return oil air mass flow rate W p The ventilation mass flow rate W of the vent valve was calculated. v2 ; The ventilation valve ventilation mass flow error iterative calculation module is used for several W v1 and W v2 If the difference meets the error requirement, then the preset bearing cavity pressure value P will be set. b1 ' Pressure value P at the initial matching point b1 The total leakage flow rate W under the preset bearing cavity pressure value s1 This is the total leakage flow rate W at the initial matching pressure point. b1 Conversely, according to W v1 and W v2 The sign and magnitude of the difference are used to reset the bearing cavity pressure value P. b1 ' Perform iterative calculations until W is reached. v1 and W v2 The difference meets the error requirements; The total ventilation flow calculation module is used to calculate W. b1 Including the leakage gas flow rate W of other bearing cavities bn Obtain the total ventilation flow rate W t ; The accessory transmission cavity pressure value calculation module is used to calculate the total ventilation flow rate W. t Obtain the pressure value P of the accessory transmission cavity. A1 ; The accessory transmission cavity pressure value error iterative calculation module is used to calculate the pressure value P of the accessory transmission cavity. A1 The preset accessory transmission chamber pressure value P A1 ' If the difference meets the error requirement, the calculation ends; otherwise, the pressure value P of the accessory transmission cavity is preset again according to the sign and magnitude of the difference. A1 ' Then, the cavity pressure matching iteration calculation is performed again until the error requirement is met.

[0023] Specifically, the total leakage flow rate and return air mass flow rate calculation module is also used to: calculate the return air mass flow rate W under the corresponding bearing cavity pressure value. pDuring the process, considering the temperature and air density under the bearing cavity pressure, the volumetric flow rate of the return oil pump is converted into the mass flow rate.

[0024] Specifically, such as Figure 5 As shown, the accessory transmission chamber pressure value calculation module includes: The characteristic curve acquisition module is used to acquire the ventilation volume-cavity pressure characteristic curve of the accessory transmission cavity; The pressure value calculation module is used to calculate the total ventilation flow rate W. t Substituting the airflow-pressure characteristic curve of the accessory transmission cavity, the pressure value P of the accessory transmission cavity is obtained. A1 .

[0025] like Figure 6 As shown, a preferred embodiment of this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps of the oil return ventilation system cavity pressure matching calculation method in the above embodiments.

[0026] like Figure 7 As shown, a preferred embodiment of this application also provides a computer device, which may be a terminal or a liveness detection server, and its internal structure diagram may be as follows: Figure 7 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The network interface is used to communicate with other external computer devices via a network connection. When the computer program is executed by the processor, it implements the steps of the aforementioned method for calculating the cavity pressure matching of the return oil ventilation system.

[0027] Those skilled in the art will understand that Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0028] A preferred embodiment of this application also provides a storage medium, the storage medium including a stored program, which, when the program is executed, controls the device where the storage medium is located to perform the steps of the oil return ventilation system cavity pressure matching calculation method in the above embodiments.

[0029] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system with a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0030] If the functions described in this embodiment are implemented as software functional units and sold or used as independent products, they can be stored in one or more computing device-readable storage media. Based on this understanding, the parts of this application's embodiments that contribute to the prior art or the technical solutions can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause a computing device (which may be a personal computer, server, mobile computing device, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage media include: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0031] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0032] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0033] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0034] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0035] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0036] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for calculating cavity pressure matching in an oil return ventilation system, characterized in that, Including the following steps: S1. The working temperature, return oil temperature and cavity temperature of the sealing device inside the bearing cavity are obtained through bearing cavity thermal analysis. S2. Based on the sealing pressure, the leakage characteristics of the sealing device under different cavity pressures and operating temperatures of the sealing device need to be calculated; the mass flow rate characteristics of the air drawn by the return oil pump under different cavity pressures and return oil temperatures need to be calculated; the throttling characteristics of the vent valve orifice need to be calculated under different cavity pressures and return oil temperatures; the oil supply flow rate characteristics of the bearing cavity need to be calculated under different cavity pressures; the flow resistance characteristics of the ventilation pipe need to be calculated; and the flow resistance characteristics of the ventilator need to be calculated. S3. Establish a cavity pressure calculation model based on the above characteristics; S4. Preset a bearing cavity pressure value P. b1 ' Substituting into the cavity pressure calculation model, the total leakage flow W under the preset bearing cavity pressure value is obtained. s1 , corresponding bearing cavity pressure value, return oil air mass flow rate W p The method calculates the return air mass flow rate W under the corresponding bearing cavity pressure value. p During the process, considering the bearing cavity temperature and the air density under cavity pressure, the volumetric flow rate of the return oil pump is converted into the mass flow rate. S5. Preset an accessory transmission chamber pressure value P. A1 ' According to the pressure value P of the accessory transmission cavity A1 ' Calculate the pressure difference before and after the throttle orifice to obtain the actual ventilation mass flow rate W through the vent valve under the corresponding pressure difference. v1 ; S6, based on the total leakage flow W s1 and return oil air mass flow rate W p The ventilation mass flow rate W of the vent valve was calculated. v2 ; S7, if W v1 and W v2 If the difference meets the error requirement, then the preset bearing cavity pressure value P will be set. b1 ' Pressure value P at the initial matching point b1 The total leakage flow rate W under the preset bearing cavity pressure value s1 This is the total leakage flow rate W at the initial matching pressure point. b1 Conversely, according to W v1 and W v2 The sign and magnitude of the difference are used to reset the bearing cavity pressure value P. b1 ' Perform iterative calculations until W is reached. v1 and W v2 The difference meets the error requirements; S8, W b1 Including the leakage gas flow rate W of other bearing cavities bn Obtain the total ventilation flow rate W t ; S9. Based on the total ventilation flow rate W t Obtain the pressure value P of the accessory transmission cavity. A1 The methods specifically include: S91. Obtain the ventilation volume-cavity pressure characteristic curve of the accessory transmission cavity; S92, the total ventilation flow rate W t Substituting the airflow-pressure characteristic curve of the accessory transmission cavity, the pressure value P of the accessory transmission cavity is obtained. A1 ; S10. If the pressure value P of the accessory transmission cavity A1 The preset accessory transmission chamber pressure value P A1 ' If the difference meets the error requirement, the calculation ends; otherwise, the pressure value P of the accessory transmission cavity is preset again according to the sign and magnitude of the difference. A1 ' Then, the cavity pressure matching iteration calculation is performed again until the error requirement is met.

2. A cavity pressure matching calculation device for an oil return ventilation system, characterized in that, include: The bearing cavity thermal analysis module is used to obtain the working temperature, return oil temperature and cavity temperature of the sealing device inside the bearing cavity through bearing cavity thermal analysis. The characteristic calculation module is used to calculate the leakage characteristics of the sealing device under different cavity pressures and operating temperatures of the sealing device based on the sealing pressure; calculate the mass flow rate characteristics of the air drawn by the return oil pump under different cavity pressures and return oil temperatures; calculate the throttling characteristics of the vent valve orifice under different cavity pressures and return oil temperatures; calculate the oil supply flow rate characteristics of the bearing cavity under different cavity pressures; calculate the flow resistance characteristics of the ventilation pipe; and calculate the flow resistance characteristics of the ventilator. The cavity pressure calculation model establishment module is used to establish a cavity pressure calculation model based on the above characteristics; The module for calculating total leakage flow and return oil air mass flow is used to preset a bearing cavity pressure value P. b1 ' Substituting into the cavity pressure calculation model, the total leakage flow W under the preset bearing cavity pressure value is obtained. s1 , corresponding bearing cavity pressure value, return oil air mass flow rate W p The device calculates the return oil air mass flow rate W under the corresponding bearing cavity pressure value. p During the process, considering the bearing cavity temperature and the air density under cavity pressure, the volumetric flow rate of the return oil pump is converted into the mass flow rate. The actual ventilation mass flow rate calculation module is used to preset an accessory transmission chamber pressure value P. A1 ' According to the pressure value P of the accessory transmission cavity A1 ' Calculate the pressure difference before and after the throttle orifice to obtain the actual ventilation mass flow rate W through the vent valve under the corresponding pressure difference. v1 ; The ventilation mass flow calculation module for the vent valve is used to calculate the total leakage flow W. s1 and return oil air mass flow rate W p The ventilation mass flow rate W of the vent valve was calculated. v2 ; The ventilation valve ventilation mass flow error iterative calculation module is used for several W v1 and W v2 If the difference meets the error requirement, then the preset bearing cavity pressure value P will be set. b1 ' Pressure value P at the initial matching point b1 The total leakage flow rate W under the preset bearing cavity pressure value s1 This is the total leakage flow rate W at the initial matching pressure point. b1 Conversely, according to W v1 and W v2 The sign and magnitude of the difference are used to reset the bearing cavity pressure value P. b1 ' Perform iterative calculations until W is reached. v1 and W v2 The difference meets the error requirements; The total ventilation flow calculation module is used to calculate W. b1 Including the leakage gas flow rate W of other bearing cavities bn Obtain the total ventilation flow rate W t ; The accessory transmission cavity pressure value calculation module is used to calculate the total ventilation flow rate W. t Obtain the pressure value P of the accessory transmission cavity. A1 The accessory transmission chamber pressure value calculation module of the device includes: The characteristic curve acquisition module is used to acquire the ventilation volume-cavity pressure characteristic curve of the accessory transmission cavity; The pressure value calculation module is used to calculate the total ventilation flow rate W. t Substituting the airflow-pressure characteristic curve of the accessory transmission cavity, the pressure value P of the accessory transmission cavity is obtained. A1 ; The accessory transmission cavity pressure value error iterative calculation module is used to calculate the pressure value P of the accessory transmission cavity. A1 The preset accessory transmission chamber pressure value P A1 ' If the difference meets the error requirement, the calculation ends; otherwise, the pressure value P of the accessory transmission cavity is preset again according to the sign and magnitude of the difference. A1 ' Then, the cavity pressure matching iteration calculation is performed again until the error requirement is met.

3. An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the cavity pressure matching calculation method for the oil return ventilation system as described in claim 1.

4. A storage medium comprising a stored program, characterized in that, When the program is running, it controls the device containing the storage medium to perform the steps of the oil return ventilation system cavity pressure matching calculation method as described in claim 1.

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