Hydraulic servo valve model based on node method

Abstract

The utility model provides a hydraulic servo valve model based on a node method, which comprises a servo valve module communicated with a high-pressure oil outlet, and the servo valve module is used for simulating the dynamic working characteristics of a servo valve and simulating the flow-pressure characteristics of each working port. A servo valve in the servo valve module is provided with a port P, a port A, a port B and a port T, a heat convection module is arranged at the output end of the port T, and a heat capacity module is arranged at an outlet of the heat convection module. According to the utility model, the flow-pressure characteristic of each working port can be dynamically simulated through the servo valve module, and the internal heat generation and transfer process of the servo valve can be simulated, so that the heat transfer efficiency of the servo valve can be improved. Modeling of the temperature change process of hydraulic oil in the servo valve is carried out, dynamic simulation analysis of the invalid power of the servo valve is achieved, the product research and development efficiency is greatly improved, and the research and development production cost is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to hydraulic servo valve model technical field, concretely relates to a hydraulic servo valve model based on node method. BACKGROUND

[0002] Hydraulic servo valve is a kind of hydraulic element that is used more widely, changes the output pressure value by the change of electric current or voltage value, and is a kind of power amplification element that is used more widely in engineering.

[0003] Taking the most widely used nozzle flapper servo valve as an example, two-stage amplification components are used inside.

[0004] In the first stage, torque motor drives the flapper, and the pressure difference of the nozzles on both sides is generated when the liquid jet is generated.The nozzle generates throttling heat when the liquid jet is generated, and part of the heat is discharged from the servo valve by the internal leakage generated with the flow of hydraulic oil, and part of the heat is absorbed by the internal metal structure of the servo valve and finally exchanges heat with the environment around the servo valve.

[0005] In the second stage, the pilot control pressure value generated by the nozzle flapper controls the movement displacement of the second-stage spool, and finally the controlled liquid flow passes through the spool, discharges from the servo valve and enters the actuator, and the liquid flow also generates throttling heat when passing through the spool.

[0006] Both of the above heat generation processes occur inside the servo valve, and the heat dissipation process is transferred to the outside through the servo valve shell on the one hand, and the heat is taken out by the outflow of hydraulic oil on the other hand. At present, the most widely used in engineering is the throttling heat calculation method based on the principle of thermodynamic power loss, which is described as follows:

[0007] Using the steady-state flow energy equation of thermodynamics, the changes of kinetic energy and potential energy are ignored, and for the throttling process (without heat exchange and without useful work), the steady-state flow energy equation is:

[0008]

[0009] That is, in this state, the enthalpy of the flow into and out of the throttling device is equal, and the following is obtained:

[0010]

[0011] Or:

[0012] The last formula is simplified, and the following is derived:

[0013]

[0014] In the heat transfer analysis of the hydraulic system, when the inlet temperature upstream of the throttling device and the pressure difference between the two ends of the throttling device are known, the temperature value downstream of the throttling device can be obtained through calculation.

[0015] After checking the existing patents, the following problems are found:

[0016] After checking Patent No. CN214788283U, a mechanical feedback type electro-hydraulic pressure servo valve, the utility model patent describes a design scheme of a mechanical feedback type hydraulic servo valve, which can effectively reduce the deflection amount of the spring tube and improve the service life of the servo valve. At the same time, through the new design, the internal leakage of the servo valve can be reduced, and the heat generation of the servo valve can be reduced. However, this invention does not involve the calculation and evaluation of the heat generation of the servo valve.

[0017] After checking CN112709724B, a power level structure of an electro-hydraulic pressure servo valve, the new design scheme is used in the secondary method end of the servo valve, which can reduce the internal leakage of the secondary amplification spool and reduce the loss of invalid power. However, this invention does not involve the analysis and calculation of heat generation at the spool.

[0018] After checking CN118815957 A, a wet type direct drive rotary servo valve, this patent describes a new structure of servo valve design scheme, which can improve the working efficiency of the servo valve, but this invention does not involve the analysis and calculation of heat generation at the spool.

[0019] In the prior art, the evaluation method of the heat generation of the commonly used servo valve in engineering is to install the servo valve on a test bench, install temperature sensors and flow sensors at the P, A, B and T ports of the servo valve, and measure the flow value through the servo valve and the temperature value of the hydraulic oil entering and leaving the servo valve under various working conditions, so as to judge the internal heat generation of the servo valve.

[0020] This method can accurately obtain the internal heat generation of the servo valve and accurately measure the invalid power. However, since the measurement can only be carried out through the final test, if the temperature exceeds, it will inevitably cause a revolutionary impact on the design scheme, cause design changes, increase the product development cycle, and cause unnecessary cost loss. Utility model content

[0021] Therefore, the utility model provides a hydraulic servo valve model based on node method, which facilitates engineering and technical personnel to carry out modeling of the temperature change process of the hydraulic oil in the servo valve according to the heat generation and transmission process in the servo valve, realizes dynamic simulation analysis of the invalid power of the servo valve, and greatly reduces the cycle and cost of product development.

[0022] To solve the above technical problems, the utility model provides a kind of hydraulic servo valve model based on node method, including the servo valve module being connected with the outlet of high pressure oil liquid, servo valve module is used to simulate servo valve dynamic operating characteristics, the flow-pressure characteristics of each working port are simulated, servo valve is respectively provided with P port, A port, B port and T port four interfaces in servo valve module, the output end of T port is provided with heat convection module, is used to simulate the convection heat dissipation process to object, heat dissipation amount is simulated by setting convection heat dissipation coefficient, heat capacity module is arranged at the outlet of heat convection module;It is used to simulate the heat capacity of object, and the heat capacity of different material, different weight product is simulated by setting heat capacity, heat transfer module and heat radiation module are respectively arranged at the outlet of heat capacity module, heat transfer module is used to simulate the conduction heat exchange process to object, heat dissipation amount is simulated by setting conduction heat coefficient, heat radiation module is used to simulate the radiation heat exchange process to object, heat dissipation amount is simulated by setting radiation heat dissipation coefficient, the utility model can simulate the flow-pressure characteristics of each working port by servo valve module, and the modeling of the temperature variation process of internal hydraulic oil of servo valve can be carried out by simulating the heat generation and transmission process in servo valve, realizes the dynamic simulation analysis for servo valve invalid power, greatly improves the efficiency of product research and development, and reduces the cost of research and development.

[0023] The outlet of the heat convection module is also provided with a check valve model.

[0024] The heat capacity module and the heat radiation module are provided with an array module therebetween, and the array module is used to set a specified array and a difference value algorithm.

[0025] The hydraulic servo valve model further includes a servo valve module icon and an interface group, wherein the interface group includes a high-pressure oil interface, a return oil interface, a first oil supply interface, a second oil supply interface, and a servo valve control signal input interface.

[0026] The high-pressure oil interface, the return oil interface, the first oil supply interface, and the second oil supply interface all have mass flow and heat flow as outputs and pressure and temperature as inputs, and the servo valve control signal input interface is an input control signal for the servo valve.

[0027] Compared with the prior art, the present application has at least one of the following beneficial technical effects:

[0028] 1. The utility model discloses can carry out the heat transfer process modeling of servo valve inside through adopting node method and commercial software, realizes the simulation modeling of servo valve P, T, A, B mouth place's hydraulic oil temperature, heat, pressure, flow value etc., can be simulated and analyzed to the heat generation of the product inside designed in the design process of servo valve, and the simulation data can effectively support servo valve design scheme, promote the maturity of design scheme, and provide reference basis for subsequent development test.

[0029] 2. The utility model discloses can guarantee that the servo valve thermal simulation model established has engineering practical significance through the dimensional setting of all parameters, is more convenient for the application in engineering after model encapsulation through standard icon.

[0030] 3. The utility model discloses can greatly reduce the use threshold through the cooperation of servo valve module icon and interface group, and the engineer does not need to understand internal modeling details, only needs to identify module function through icon, can run simulation through interface input actual parameter, is convenient for realizing multi -physics field coupling analysis, and the combination makes the complex servo valve thermal simulation model into the " plug and play " tool easy to use in engineering, and the design efficiency is improved significantly. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 It is the structure schematic drawing of hydraulic servo valve model based on node method of the utility model,

[0032] Figure 2 It is the simulation model schematic drawing of hydraulic servo valve model based on node method of the utility model,

[0033] Figure 3 It is the schematic diagram of heat transfer mechanism of hydraulic servo valve model based on node method of the utility model.

[0034] EXPLANATION OF REFERENCE NUMERALS: 100, servo valve module, 200, heat convection module, 300, check valve model, 400, heat capacity module, 500, heat conduction module, 600, heat radiation module, 700, array module, 800, servo valve module icon, 900, interface group, 901, high pressure oil interface, 902, oil return interface, 903, first oil supply interface, 904, second oil supply interface, 905, servo valve control signal input interface. DETAILED DESCRIPTION

[0035] In order to make the utility model embodiment's purpose, technical scheme and advantage more clear, below will combine the utility model embodiment's attached Figures 1-3The technical solutions of the embodiments of the present application are clearly and completely described.

[0036] As shown in Figure 1 : the embodiment provides a hydraulic servo valve model based on a node method, which comprises a servo valve module 100 connected with the outlet of high-pressure oil, the servo valve module 100 is used for simulating servo valve dynamic working characteristics, and the flow-pressure characteristics of each working port are simulated, four interfaces of P port, A port, B port and T port are arranged on the servo valve in the servo valve module 100, a heat convection module 200 is arranged at the output end of the T port, and the heat convection module 200 is used for simulating the convection heat dissipation process of an object, the heat dissipation amount is simulated by setting a convection heat dissipation coefficient, a heat capacity module 400 is arranged at the outlet of the heat convection module 200; the heat capacity module 400 is used for simulating the heat capacity value of the object, the heat capacity of products with different materials and different weights is simulated by setting the heat capacity value, a heat conduction module 500 and a heat radiation module 600 are arranged at the outlet of the heat capacity module 400, the heat conduction module 500 is used for simulating the conduction heat exchange process of the object, the heat dissipation amount is simulated by setting a conduction heat coefficient, the heat radiation module 600 is used for simulating the radiation heat exchange process of the object, the heat dissipation amount is simulated by setting a radiation heat dissipation coefficient, the servo valve module 100 can be used for dynamically simulating the flow-pressure characteristics of each working port, and the modeling of the hydraulic oil temperature change process in the servo valve can be carried out by simulating the heat generation and transmission process in the servo valve, the dynamic simulation analysis of the invalid power of the servo valve is realized, the efficiency of product research and development is greatly improved, and the cost of research and development and production is reduced.

[0037] According to one embodiment of the present application, as Figure 1 and Figure 2 shown, a one-way valve model 300 is further arranged at the outlet of the heat convection module 200, the one-way valve model 300 is a hydraulic one-way valve model, and is used for controlling the one-way passing of high-pressure oil.

[0038] The heat capacity module 400 and the heat radiation module 600 are provided with an array module 700, and the array module 700 is used for setting a specified array and a difference value algorithm.

[0039] According to another embodiment of the present application, as Figure 1As shown, the servo valve simulation model is established by using the simulation modules in the model library of the mechatronic and hydraulic comprehensive simulation software AMESim, including the simulation modules in the Signal, Control and Observers sub-library, the Thermal sub-library, the Thermal Hydraulic sub-library and the Thermal Pneumatic sub-library. Figure 2 As shown, the servo valve simulation model is established by using the simulation modules in the model library of the mechatronic and hydraulic comprehensive simulation software AMESim, including the simulation modules in the Signal, Control and Observers sub-library, the Thermal sub-library, the Thermal Hydraulic sub-library and the Thermal Pneumatic sub-library.

[0040] The external parameters of the servo valve module 100 are shown in Table 1.

[0041] Table 1 External parameters of the servo valve module

[0042]

[0043] The use method of the utility model:

[0044] First of all, it needs to be clear that the simulation model involved in the utility model is mainly used for simulating and calculating the heat loss of the servo valve in the working process, so as to facilitate the technical personnel to carry out the modeling of the temperature change process of the internal hydraulic oil of the servo valve according to the heat generation and transmission process of the servo valve, realize the dynamic simulation analysis of the invalid power of the servo valve, provide reference basis for subsequent development test and design of the servo valve, and here it needs to be explained that: this scheme no longer uses the power loss method as the modeling principle, but uses the node method as the modeling method.

[0045] When the internal heat transfer process of the servo valve needs to be simulated, the modeling method is as follows:

[0046] The node method analysis is as follows: the heat transfer process of the servo valve is as shown in the figure Figure 3 As shown, the high-pressure oil enters the servo valve, generates throttling heat, drives the external equipment to work, and then enters the servo valve again to generate throttling heat. The servo valve shell performs forced convection heat transfer with the internal oil, and at the same time, performs convection heat transfer and radiation heat transfer with the external environment.

[0047] The Nusselt number of the forced convection heat transfer between the servo valve shell and the internal oil can be expressed as:

[0048]

[0049] wherein, Re is the Reynolds number, Pr is the Prandtl number.

[0050] The Nusselt number of the servo valve shell natural convection heat exchange with the external air can be expressed as:

[0051]

[0052] wherein, Pr is the Prandtl number, Re is the Reynolds number.

[0053] The radiation heat exchange amount of the servo valve shell with the environment can be expressed as:

[0054]

[0055] wherein, a is the blackness of the pipe wall material, h is the radiation heat exchange constant, T is the pipe wall temperature, T is the ambient temperature.

[0056] The utility model discloses a servo valve module 100 can carry out dynamic simulation to the flow-pressure characteristic of each working port, and can carry out the modeling of servo valve internal hydraulic oil temperature change process through simulating servo valve internal heat generation and transmission process, realizes dynamic simulation analysis to the invalid power of servo valve, improves the efficiency of product research and development greatly, and reduces the cost of research and development production.

[0057] In addition, it also needs to be explained that, in the description of the utility model, unless another explicit provision and limitation, the terms "installation", "connection", "connect" should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integrally connected, can be mechanical connection, can also be electrical connection, can be directly connected, can also be indirectly connected through the intermediate medium, can be the communication inside two elements. For ordinary skilled in the art, the above-mentioned terms can be understood according to the specific meaning of the utility model.

[0058] The above is the preferred embodiment of the utility model, it should be pointed out that, for ordinary skilled in the art, on the premise of not departing from the principle described in the utility model, can also make a number of improvements and refinements, these improvements and refinements also should be considered as the protection scope of the utility model.

Claims

1. A hydraulic servo valve model based on node method, comprising a servo valve module (100) connected with an outlet of high pressure oil, four interfaces of P port, A port, B port and T port are respectively arranged on the servo valve in the servo valve module (100), characterized in that: The output end of the T-shaped port is provided with a heat convection module (200), and the outlet of the heat convection module (200) is provided with a heat capacity module (400); the outlet of the heat capacity module (400) is respectively provided with a heat conduction module (500) and a heat radiation module (600).

2. The nodal method based hydraulic servo valve model of claim 1, wherein: The outlet of the heat convection module (200) is also provided with a one-way valve model (300).

3. The nodal method based hydraulic servo valve model of claim 2, wherein: An array module (700) is arranged between the heat capacity module (400) and the heat radiation module (600).

4. The node-based hydraulic servo valve model of claim 3, wherein: The hydraulic servo valve model further comprises a servo valve module (100) icon and an interface group (900), wherein the interface group (900) comprises a high-pressure oil interface (901), an oil return interface (902), a first oil supply interface (903), a second oil supply interface (904) and a servo valve control signal input interface (905).

5. The nodal method based hydraulic servo valve model of claim 4, wherein: The high-pressure oil interface (901), the oil return interface (902), the first oil supply interface (903) and the second oil supply interface (904) all output mass flow and sulfur content, and input pressure and temperature, and the servo valve control signal input interface (905) is a control signal for inputting a servo valve.

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