CN113569454A - Simulation analysis method for diesel engine valve actuating mechanism - Google Patents
Simulation analysis method for diesel engine valve actuating mechanism Download PDFInfo
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Abstract
本发明公开了一种柴油机配气机构的模拟分析方法，包括如下步骤：S1：温度场分析：使用模拟燃烧的方法，直接模拟柴油机燃烧室内燃料的燃烧反应，获得燃气温度场，并通过壁面换热得到燃烧室的壁面温度场，从而获得组件温度场；S2：热力耦合分析：对配气机构整体进行系统的热力耦合分析；S3：合理间隙分析：分析出热工作环境下，柴油机活塞与气缸、活塞与气门、气门与气门横臂之间的热变形，进而得到冷态下三组组件之间针对热变形应预留的合理间隙。为分析柴油机温度场提供一种新途径，同时本发明所获得的组件之间的间隙已应用在工厂实践中，证明本发明的研究结果对柴油机的设计应用上具有一定的参考价值，为配气机构优化设计和制造安装提供了依据。
The invention discloses a simulation analysis method of a diesel engine valve train, comprising the following steps: S1: temperature field analysis: using the method of simulating combustion, directly simulating the combustion reaction of fuel in the combustion chamber of the diesel engine, obtaining the gas temperature field, and changing the temperature through the wall surface. Thermally obtain the wall temperature field of the combustion chamber, thereby obtaining the component temperature field; S2: Thermal coupling analysis: perform a systematic thermal coupling analysis of the valve train as a whole; S3: Reasonable clearance analysis: analyze the thermal working environment, the piston and cylinder of the diesel engine , the thermal deformation between the piston and the valve, the valve and the valve cross arm, and then obtain the reasonable gap that should be reserved for thermal deformation between the three groups of components in the cold state. A new approach is provided for analyzing the temperature field of the diesel engine. At the same time, the gap between the components obtained by the present invention has been applied in the factory practice, which proves that the research results of the present invention have a certain reference value for the design and application of the diesel engine. The mechanism optimization design and manufacture and installation provide the basis.
Description
Technical Field
The invention relates to the technical field of chemical machinery, in particular to a simulation analysis method for a valve actuating mechanism of a diesel engine.
Background
The valve actuating mechanism is used as an important component of a diesel engine, the size of a reasonable gap between components of the valve actuating mechanism directly influences the stable working performance of the diesel engine, and the improper gap can cause the faults of cylinder pulling, valve impact by a piston, valve knocking by a valve cross arm and the like, so that the diesel engine cannot normally work, and therefore, the analysis of the reasonable gap between the components of the valve actuating mechanism of the diesel engine is very necessary.
(1) According to the traditional method, the wall surface temperature field of the combustion chamber is simulated by measuring point temperature or an empirical formula, and the analysis result is greatly different from the actual working condition.
(2) The traditional analysis method is to analyze the thermal coupling of a certain component or certain components of the air distribution system, the invention analyzes the thermal coupling of the whole air distribution mechanism to obtain the distribution rule of the stress strain and the thermal deformation of the air distribution mechanism, the analysis method is obviously superior to the traditional method, and the analysis method has few reports.
(3) According to the invention, the variation of the clearances between the cylinder sleeve and the piston, between the piston and the valve and between the valve and the valve cross arm is obtained according to simulation analysis, so that reasonable clearances which are reserved among three groups of components in a cold state are obtained, and the analysis process is not reported at present.
Disclosure of Invention
The invention aims to provide a simulation analysis method of a diesel engine valve actuating mechanism, which aims to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme:
a simulation analysis method of a diesel engine valve actuating mechanism comprises the following steps:
s1: analysis of the temperature field: directly simulating the combustion reaction of fuel in a combustion chamber of the diesel engine by using a combustion simulation method to obtain a gas temperature field, and obtaining a wall surface temperature field of the combustion chamber through wall surface heat exchange to obtain a component temperature field;
s2: analysis of the thermodynamic coupling: carrying out systematic thermal coupling analysis on the whole valve actuating mechanism;
s3: analysis of rational gaps: thermal deformation between a piston and a cylinder of the diesel engine, between the piston and a valve and between the valve and a valve cross arm in a hot working environment is analyzed, and further reasonable gaps which are reserved for the thermal deformation between the three groups of components in a cold state are obtained.
Further, the analysis of the temperature field of the gas and the wall surface in the cylinder of the diesel engine in the step 1 comprises combustion simulation analysis and establishment of a finite element analysis model.
Further, the combustion simulation analysis adopts a method of simulating combustion to analyze the temperature field of the inner wall surface of the cylinder, and the specific content is as follows:
(6) utilizing Creo 3.0 software to establish a three-dimensional geometric model of a valve mechanism according to the basic structure parameters of the 265 diesel engine;
(7) establishing a model of a combustion area by using a DesignModelr module in Ansys Workbench19.0 software;
(8) introducing the combustion finite element model into Fluent 19.0 software for combustion simulation to obtain a temperature field of the in-cylinder combustion gas;
(9) obtaining a temperature field of the inner wall surface of the cylinder in Fluent 19.0 software by a wall surface heat exchange method;
(10) establishing a thermal analysis finite element model by using Ansys Workbench19.0 software;
(6) and taking the wall surface temperature field obtained by combustion analysis as a boundary condition, and obtaining the temperature field of the valve train through heat conduction and heat radiation.
Further, a three-dimensional geometric model built in the Creo 3.0 software is imported into the Ansys workbench19.0 software, a 265 diesel engine valve train finite element analysis model is built, and the process of building the finite element analysis model comprises the following steps:
(6) establishing an in-cylinder combustion area;
(7) setting corresponding material parameters for different wall surfaces according to actual conditions;
(8) simulating the influence of a cooling system on the wall surface temperature according to the actual condition of the diesel engine;
(9) selecting fuel which can be used for replacing diesel components in simulation according to related research results at home and abroad, and setting design parameters of reactants, reaction steps and products;
(10) the inlet flow, temperature and pressure are set and relaxation factors are added.
Further, for the establishment of the in-cylinder combustion area, according to the actual working condition, a three-dimensional model is led into Ansys workbench19.0 software, a design normal model module is used for establishing the in-cylinder combustion area, and the combustion area selects the inner wall of the cylinder sleeve, the upper surface of the piston, the cylinder cover and the valve as boundaries according to the actual working condition.
Further, for the setting of the material parameters, the wall surface of the entire combustion area is divided into 11 independent wall surfaces, and then different material properties are added to different contact surfaces according to actual conditions.
Further, the analysis and calculation of the thermal coupling of the valve train component of S2 is to constrain the constraint surface in three working conditions, namely, intake working condition, compression and explosion working condition, and exhaust working condition, for the pressure characteristics inside the combustion chamber under different working conditions, and then two methods are used to load the internal pressure, namely, loading the steady-state pressure inside the intake and exhaust working conditions, loading the variable pressure of the compression and explosion working conditions, and analyzing the equivalent stress and strain of the valve train component.
Further, in S3, the 265 diesel engine cylinder gas temperature field and the component temperature field are analyzed, then the thermal coupling analysis is performed on the valve train, and the reasonable gap between the valve train components is calculated, specifically the following operations are performed:
s301: performing three-dimensional entity modeling by using Creo 3.0 software;
s302: simulating the internal combustion environment of the combustion chamber of the diesel engine by using Fluent 19.0 software to obtain a steady-state temperature field of the wall surface of the combustion chamber and the pressure born by the inner wall surface of the cylinder during intake and exhaust strokes;
s303: using Ansys Workbench19.0 software, taking a wall surface temperature field obtained by combustion analysis as an initial condition, and obtaining a valve train component temperature field by adopting a heat transfer theory;
s304: using Ansys Workbench19.0 software, and utilizing the obtained component temperature field to perform thermal coupling analysis on the valve mechanism, wherein the analysis is divided into three working conditions and two pressure loading modes, so that the distribution rule of equivalent stress, strain and deformation of each component of the valve mechanism is obtained;
s301: and analyzing the clearances among the three groups of components, namely the cylinder sleeve and the piston, the piston and the valve, and the valve cross arm by using Ansys Workbench19.0 software, and further analyzing the reasonable clearances which are reserved among the three groups of components in a cold environment.
Compared with the prior art, the invention has the beneficial effects that:
(1) according to the analysis of the temperature field, the combustion simulation method is used for directly simulating the combustion reaction of the fuel in the combustion chamber of the diesel engine to obtain the gas temperature field, the wall surface temperature field of the combustion chamber is obtained through wall surface heat exchange, so that the component temperature field is obtained, and the wall surface temperature obtained by the method is proved to be closer to the actual working condition after being compared with the experiment of a factory.
(2) The invention analyzes the thermodynamic coupling of the whole valve mechanism, considers the mutual influence among the components, and leads the final analysis result to have smaller error and to be closer to the reality.
(3) The invention analyzes the thermal deformation between the piston and the cylinder, between the piston and the valve, and between the valve and the valve cross arm of the diesel engine under the hot working environment, so as to obtain the reasonable clearance which is reserved between the three groups of components under the cold state aiming at the thermal deformation, and the analysis result is already applied to the actual regulation of the clearance of the valve mechanism of the diesel engine in a factory, thereby obtaining good effect.
Through the research on the three aspects, a new way is provided for obtaining the temperature field of the assembly, a reference closer to the actual situation is provided for solving the internal thermal coupling situation of the diesel engine, and a theoretical basis is provided for the relevant design and adjustment of the valve train.
Drawings
FIG. 1 is a front schematic view of a valve train assembly of the present invention;
FIG. 2 is an exploded view of FIG. 1 in accordance with the present invention;
FIG. 3 is a side schematic view of a valve train assembly of the present invention;
FIG. 4 is an exploded view of FIG. 2 of the present invention;
FIG. 5 is a top view of the valve train assembly of the present invention;
FIG. 6 is an exploded view of FIG. 5 in accordance with the present invention;
FIG. 7 is a schematic view of the distribution of piston measuring points according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
A simulation analysis method of a diesel engine valve actuating mechanism comprises the following steps:
s1: analysis of the temperature field: directly simulating the combustion reaction of fuel in a combustion chamber of the diesel engine by using a combustion simulation method to obtain a gas temperature field, and obtaining a wall surface temperature field of the combustion chamber through wall surface heat exchange to obtain a component temperature field;
s2: analysis of the thermodynamic coupling: carrying out systematic thermal coupling analysis on the whole valve actuating mechanism;
s3: analysis of rational gaps: thermal deformation between a piston and a cylinder of the diesel engine, between the piston and a valve and between the valve and a valve cross arm in a hot working environment is analyzed, and further reasonable gaps which are reserved for the thermal deformation between the three groups of components in a cold state are obtained.
Analyzing a gas temperature field and a component temperature field in a 265 diesel engine cylinder, then performing thermal coupling analysis on a valve mechanism, and calculating a reasonable gap between valve mechanism components, wherein the specific operation is as follows:
(1) performing three-dimensional entity modeling by using Creo 3.0 software;
(2) simulating the internal combustion environment of the combustion chamber of the diesel engine by using Fluent 19.0 software to obtain a steady-state temperature field of the wall surface of the combustion chamber and the pressure born by the inner wall surface of the cylinder during intake and exhaust strokes;
(3) and (3) acquiring a temperature field of the valve train component by using an Ansys Workbench19.0 software and using a wall surface temperature field obtained by combustion analysis as an initial condition and adopting a heat transfer theory.
(4) Using Ansys Workbench19.0 software, and utilizing the obtained component temperature field to perform thermal coupling analysis on the valve mechanism, wherein the analysis is divided into three working conditions (namely, an air inlet working condition, a compression and explosion working condition and an exhaust working condition) and two pressure loading modes (namely, loading steady-state pressure on the air inlet working condition and the exhaust working condition and loading variable pressure on the compression working condition and the explosion working condition), so that the distribution rules of equivalent stress, strain and deformation of each component of the valve mechanism are obtained;
(5) and analyzing the clearances among the three groups of components, namely the cylinder sleeve and the piston, the piston and the valve, and the valve cross arm by using Ansys Workbench19.0 software, and further analyzing the reasonable clearances which are reserved among the three groups of components in a cold environment.
The principle of the invention is as follows:
theory of combustion
1. Fluid dynamics control equation
(1) Equation of continuity
The differential form of the continuity equation is:
(2) equation of conservation of momentum
The conservation of momentum equation satisfies newton's second law. The momentum equations of the x, y and z directions can be derived according to the law:
(3) energy conservation equation
The expression form is:
2. turbulence model
And selecting a turbulence model as a K-epsilon standard model. The expression form of the turbulence model equation in a Cartesian coordinate system is as follows:
turbulent kinetic energy K equation:
turbulent dissipation ratio epsilon equation:
3. combustion model
The combustion model selected is a hybrid model. The reaction rates of both the eddy current dissipation model and the finite rate model were calculated. The minimum reaction rate in the two models was taken as the final reaction rate.
Finite rate model: the mathematical expression is as follows:
eddy current dissipation model: the mathematical expression is: f + So＝(1+S)p、
Theory of heat transfer
The theory of heat transfer defines that the temperature of a substance varies with time τ and space, and is expressed as: t ═ f (x, y, z, τ).
Establishing a heat conduction differential equation according to energy conservation and Fourier law
Secondly, analyzing the temperature field of the gas and the wall surface in the cylinder
Combustion simulation analysis
Thirdly, analyzing the temperature field of the inner wall surface of the cylinder by adopting a simulated combustion method, wherein the specific content is as follows: (1) utilizing Creo 3.0 software to establish a three-dimensional geometric model of a valve mechanism according to the basic structure parameters of the 265 diesel engine; (2) establishing a model of a combustion area by using a DesignModelr module in Ansys Workbench19.0 software; (3) introducing the combustion finite element model into Fluent 19.0 software for combustion simulation to obtain a temperature field of the in-cylinder combustion gas; (4) obtaining a temperature field of the inner wall surface of the cylinder in Fluent 19.0 software by a wall surface heat exchange method; (5) establishing a thermal analysis finite element model by using Ansys Workbench19.0 software; (6) and taking the wall surface temperature field obtained by combustion analysis as a boundary condition, and obtaining the temperature field of the valve train through heat conduction and heat radiation.
TABLE 1 intake valve Primary size
TABLE 2 exhaust valve Primary measurements
TABLE 3 piston Primary dimensions
TABLE 4 camshaft principal parameters
TABLE 5 other Components essential parameters
(II) establishing finite element analysis model
The three-dimensional geometric model established in the Creo 3.0 software is imported into the Ansys Workbench19.0 software, a 265 diesel engine valve mechanism finite element analysis model is established, and the model establishing process comprises the following steps: (1) establishing an in-cylinder combustion area; (2) setting corresponding material parameters for different wall surfaces according to actual conditions; (3) simulating the influence of a cooling system on the wall surface temperature according to the actual condition of the diesel engine; (4) selecting fuel which can be used for replacing diesel components in simulation according to related research results at home and abroad, and setting design parameters of reactants, reaction steps and products; (5) the inlet flow, temperature and pressure are set and relaxation factors are added.
1. In-cylinder combustion zone establishment
And (3) introducing the three-dimensional model into Ansys Workbench19.0 software according to the actual working condition, and establishing a combustion area inside the cylinder by using a DesignModelr module. And selecting the inner wall of the cylinder sleeve, the upper surface of the piston, the cylinder cover and the valve as boundaries in the combustion area according to actual working conditions.
2. Setting of material parameters
The wall surface of the whole combustion area is divided into 11 independent wall surfaces, and different material properties are added on different contact surfaces according to actual conditions.
TABLE 6 Combustion wall Assembly Material Properties
2. Setting of combustion parameters
The invention uses n-heptane (C)7H16) As a reactant. The fuel-air mixture in the diesel engine is mainly diesel oil and air, so the reactant setting parameter of the air inlet is n-heptane (C)7H16) Oxygen (O)2) Nitrogen (N)2) The product composition of the exhaust port is defined as water (H)2O), dioxygenCarbon (CO)2) Nitrogen (N)2)。
The combustion process uses a two-step combustion process, defining the reaction intermediate as carbon monoxide (CO), and the reaction equation is as follows:
4. air inlet and outlet and relaxation factor setting
According to test data provided by a factory, the total air input of the 16-cylinder diesel engine is 9.2kg/s, so that the air inlet flow of a single cylinder is set to be 0.575kg/s, meanwhile, the turbocharging of the air inlet pipe is 0.19MPa, so that the pressure of 0.19MPa is increased on the basis of standard atmospheric pressure as the input pressure of an air inlet, the entering temperature of an oil-gas mixture at the air inlet of the cylinder cover is 65 ℃, the exhaust mode of an exhaust port is set to be pressure exhaust, and the external atmospheric pressure is standard atmospheric pressure.
The single cylinder sets the air intake flow to be 0.575kg/s, and in the solving process, the pressure relaxation factor is set to be 0.6, the density relaxation factor is 1, the momentum relaxation factor is 0.7, and the relaxation factors of the turbulent kinetic energy and the turbulent dissipation are 0.8.
5. Computational analysis of heat transfer coefficient
And selecting the temperatures of the characteristic points by using Fluent 19.0 software to perform temperature assignment on the wall surfaces respectively, performing combustion simulation on in-cylinder gas after the temperature assignment, calculating the heat transfer coefficients of the wall surfaces at different temperatures, and taking the average value of the heat transfer coefficients on each wall surface as a boundary condition for loading.
Referring to fig. 1-7, according to different test point temperatures provided by a factory, the invention utilizes Fluent 19.0 software to select the temperatures of the following characteristic points to respectively assign the temperatures to the wall surfaces, the structural shape of the piston wall surface is complex, so the piston characteristic points select 10 points in a piston top surface curve on the piston section vertical to the central axis of the piston pin hole, wherein the point 1 is on the top surface of the piston on the exhaust valve side and is 125mm away from the central axis of the piston, the point 2 is 102mm away from the central axis, the point 3 is 72mm away from the central axis, the point 4 is 44mm away from the central axis, the point 5 is 15mm away from the central axis, and the points 6 to 10 are respectively symmetrical to the point 5 to the point 1 about the central axis, so that the distribution rule of the piston wall surface temperatures can be completely reflected; the contact area of the wall surface of the cylinder sleeve and gas is larger, so that 8 points on the inner wall of two sections parallel and vertical to the section of the piston are selected as the characteristic points of the cylinder sleeve, wherein the distance between the point 1-4 and the top surface lOmm of the cylinder sleeve is larger, and the distance between the point 5-8 and the top surface 32mm of the cylinder sleeve is larger, so that the distribution rule of the temperature of the wall surface of the cylinder sleeve can be more completely reflected; the wall surface area of the air inlet valve is small, the structural shape is simple, so that the characteristic points of the air inlet valve are 4 points on the same diameter of the gas side wall surface of the air inlet valve, wherein the point 1 is positioned at the center of a circle, the point 2 is 15mm away from the center of a circle, the point 3 is 30mm away from the center of a circle, and the point 4 is 42mm away from the center of a circle; the area and the structure of the wall surface of the exhaust valve and the wall surface of the intake valve are approximately the same, but the temperature distribution of the position of the exhaust valve is more complex and the valve fault is more likely to occur on the exhaust valve, so the characteristic point of the exhaust valve selects 7 points on two mutually perpendicular diameters of the gas side wall surface of the exhaust valve, wherein the point 1 is positioned at the center of a circle, the points 2 and 5 are 15mm away from the center of a circle, the points 3 and 6 are 30mm away from the center of a circle, and the points 4 and 7 are 40mm away from the center of a circle. And after temperature assignment, carrying out combustion simulation on in-cylinder gas, and calculating the heat transfer coefficients of all wall surfaces at different temperatures.
6. Simulation of a cooling system
Considering the influence of the wall thickness of the cylinder sleeve on temperature transmission, the external environment temperature of the wall surface of the cylinder sleeve is set to be 350K, which is about 78 ℃.
(I) creation of finite element analysis model
The finite element analysis process of the temperature field of the valve train is as follows: (1) adopting Ansys Workbench19.0 software to reestablish a three-dimensional finite element model, carrying out mesh division and material parameter setting, and redefining a contact relation; (2) introducing the temperature field of the cylinder inner wall surface obtained in the previous step into Ansys Workbench19.0 software as an initial condition and defining other boundary conditions; (3) and calculating and analyzing to obtain the whole temperature field of the valve train, and carrying out detailed analysis on the temperature distribution of the main components.
1. Meshing, material parameter setting and defining mechanism contact
And (3) importing the 265 diesel engine three-dimensional model into Ansys Workbench19.0 software, and redefining the contact relation of the main components.
2. Setting of the temperature field
The setting of the temperature field comprises three parts: setting of in-cylinder temperature, setting of external component temperature, setting of cooling system temperature.
(1) Setting of in-cylinder temperature. The wall temperature field was directly introduced into the Ansys Workbench19.0 software as the initial condition for analyzing the valve train component temperature field.
(2) Setting of the temperature of the external component. Factory supplied data is used as boundary conditions.
(3) And setting the temperature of the cooling system. The position is analyzed in a thermal radiation manner.
(4) And setting the overall temperature field. According to the steps (1) to (3), the initial temperature boundary condition is loaded in two modes, the temperature field of the inner wall surface of the cylinder is directly introduced into the Ansys Workbench19.0 by Fluent 19.0 software, and the external component temperature and the cooling system temperature are directly loaded on the corresponding wall surface.
Fourthly, analysis and calculation of thermal coupling of valve train assembly
According to the pressure characteristics of the interior of the combustion chamber under different working conditions, the constraint surface is constrained under three working conditions, namely an air inlet working condition, a compression and explosion working condition and an exhaust working condition, the internal pressure is loaded by two methods, namely the steady-state pressure is loaded in the air inlet working condition and the exhaust working condition, the variable pressure is loaded in the compression and explosion working conditions, and the equivalent stress and the strain of the valve mechanism assembly are analyzed.
1. Constraint conditions
(1) And (3) air inlet working condition: the valve cross arm pushes the tail end of the air inlet valve group to open the valve, and the mixed gas enters the combustion chamber through the air inlet channel, so that all degrees of freedom of the top surface of the valve cross arm at the top of the air inlet valve group are restrained. In the state, the exhaust valve group is in a closed state, the top end of the valve is separated from the valve cross arm, the back surface of the valve head of the exhaust valve group is tightly attached to the valve seat ring, and the movement of the valve in the axial direction is limited, so that the exhaust valve restrains the movement of the contact surface of the back part of the valve head and the valve seat ring in the axial direction of the valve;
(2) compression and explosion strokes: the air inlet valve group and the air outlet valve group are both in a closed state, the top end of the air inlet valve group is separated from the air valve cross arm, and the back surface of the valve head of the air valve group is tightly attached to the air valve seat ring, so that the movement of the contact surface of the rear parts of the valve heads of the air inlet valve and the air outlet valve and the air valve seat ring in the axial direction of the air valve is restrained;
(3) exhaust stroke: the valve cross arm pushes the tail end of the exhaust valve group to open the valve, and gas in the cylinder is exhausted out of the combustion chamber through the exhaust valve group and enters an exhaust pipeline, so that all degrees of freedom of the top surface of the valve cross arm at the top of the exhaust valve group are restrained. The air inlet valve set in the state is in a closed state, the top end of the air valve is separated from the air valve cross arm, the back surface of the valve head of the air inlet valve set is tightly attached to the air valve seat ring, and the movement of the valve in the axial direction is limited, so that the movement of the contact surface of the rear part of the valve head of the air inlet valve and the air valve seat ring in the axial direction of the air valve is restrained.
2. Pressure load
The in-cylinder pressure is loaded in two ways. When the engine is in compression and explosion working conditions, 4 valves are closed, and the pressure in the cylinder changes constantly due to the reciprocating motion of the piston, so that the changed pressure needs to be loaded on a valve head surface of the valve, the inner wall of the cylinder (the area above the piston), the top surface of the piston and the surface of the cylinder cover, and the pressure assignment is carried out on the inner wall surface of the combustion chamber according to the pressure measured by the crankshaft of the engine at different angles.
(II) reasonable clearance calculation of gas distribution system
The deformation analysis of the whole valve actuating mechanism is carried out according to three working conditions to obtain the conclusion:
(1) the temperature field of the in-cylinder combustion gas and the temperature field of the wall surface obtained by the combustion simulation method are reasonable and reliable.
(2) The result of analyzing the data of the clearances which are reserved between the piston and the valve and between the valve and the valve cross arm in the cold state is reasonable and reliable.
The technical scheme is that a combustion simulation method is adopted to analyze the temperature field of the gas in the cylinder of the gas distribution mechanism, the distribution rule of the gas flow rate, the gas temperature, the wall surface temperature, the heat flow density and the pressure in the cylinder is obtained, the temperature field of a component of the gas distribution mechanism is analyzed by taking the temperature field of the wall surface obtained by simulation as a boundary condition, then the temperature field of the component obtained by analysis is taken as the boundary condition, the thermal coupling analysis is carried out on the gas distribution mechanism according to three working conditions of air inlet, compression, explosion and air exhaust, the equivalent stress, the strain and the deformation of the component are obtained, and finally the reasonable clearances which are reserved between a piston and a cylinder sleeve, between the piston and a valve and between the valve and a valve cross arm in a cold state are analyzed according to the deformation of the component obtained by the thermal coupling analysis.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical solutions and the inventive concepts of the present invention within the technical scope of the present invention.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004239129A (en) * | 2003-02-05 | 2004-08-26 | Mazda Motor Corp | Predicting analyzing method of engine performance, predicting analyzing system and its control program |
| CN103034784A (en) * | 2012-12-15 | 2013-04-10 | 福州大学 | Diesel engine air distribution system dynamic calculation method based on multi-body system transfer matrix |
| CN103034744A (en) * | 2011-10-08 | 2013-04-10 | 唐文献 | Simulation method of temperature field of cylinder head of low-speed diesel engine |
| RU2011152714A (en) * | 2011-12-22 | 2013-06-27 | Федеральное Государственное Бюджетное Образовательное Учреждение Высшего Профессионального Образования "Пензенский Государственный Университет Архитектуры И Строительства" | METHOD AND INSTALLATION FOR RESEARCH OF PROCESSES OF AGING OF MOTOR OILS |
| DE102014103145A1 (en) * | 2014-03-10 | 2015-09-10 | Dr. Ing. H.C. F. Porsche Aktiengesellschaft | Method and engine control unit for operating an internal combustion engine |
| CN108363857A (en) * | 2018-02-05 | 2018-08-03 | 燕山大学 | Recuperative heater flow field and inside workpiece temperature, thermal-stress analysis method |
| CN108573081A (en) * | 2017-07-05 | 2018-09-25 | 常州星宇车灯股份有限公司 | A kind of thermal deformation analysis method of Thermal-mechanical Coupling simulated automotive lamp reflector |
| US20210013820A1 (en) * | 2019-01-10 | 2021-01-14 | Hunan University Of Science And Technology | Modeling method of stator winding air gap for temperature field analysis of ac traction motor |
| CN112733294A (en) * | 2021-01-11 | 2021-04-30 | 重庆长安汽车股份有限公司 | Design method of engine cylinder gasket |
-
2021
- 2021-08-04 CN CN202110888993.0A patent/CN113569454B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004239129A (en) * | 2003-02-05 | 2004-08-26 | Mazda Motor Corp | Predicting analyzing method of engine performance, predicting analyzing system and its control program |
| CN103034744A (en) * | 2011-10-08 | 2013-04-10 | 唐文献 | Simulation method of temperature field of cylinder head of low-speed diesel engine |
| RU2011152714A (en) * | 2011-12-22 | 2013-06-27 | Федеральное Государственное Бюджетное Образовательное Учреждение Высшего Профессионального Образования "Пензенский Государственный Университет Архитектуры И Строительства" | METHOD AND INSTALLATION FOR RESEARCH OF PROCESSES OF AGING OF MOTOR OILS |
| CN103034784A (en) * | 2012-12-15 | 2013-04-10 | 福州大学 | Diesel engine air distribution system dynamic calculation method based on multi-body system transfer matrix |
| DE102014103145A1 (en) * | 2014-03-10 | 2015-09-10 | Dr. Ing. H.C. F. Porsche Aktiengesellschaft | Method and engine control unit for operating an internal combustion engine |
| CN108573081A (en) * | 2017-07-05 | 2018-09-25 | 常州星宇车灯股份有限公司 | A kind of thermal deformation analysis method of Thermal-mechanical Coupling simulated automotive lamp reflector |
| CN108363857A (en) * | 2018-02-05 | 2018-08-03 | 燕山大学 | Recuperative heater flow field and inside workpiece temperature, thermal-stress analysis method |
| US20210013820A1 (en) * | 2019-01-10 | 2021-01-14 | Hunan University Of Science And Technology | Modeling method of stator winding air gap for temperature field analysis of ac traction motor |
| CN112733294A (en) * | 2021-01-11 | 2021-04-30 | 重庆长安汽车股份有限公司 | Design method of engine cylinder gasket |
Non-Patent Citations (2)
| Title |
|---|
| 赵宏国;白敏丽;王宇;吕继组;周龙;: "耦合法在柴油机传热研究中的应用", 小型内燃机与摩托车, no. 06 * |
| 赵立普;王静超;徐天舒;张俊红;: "考虑进气冷却的柴油机活塞温度场分析", 车用发动机, no. 02 * |
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