| The concept of digital virtual engine has been accepted by more and more engine R&D Engineer. Compared with the traditional engine development process, digital virtual engine develop technology depends on n umerical methods. Numerical engine development technology can be developed to achieve the engine performance goal for more than 90% in the conceptual design phase, that makes it develops rapidly. However, the domestic gasoline engine performance conceptual design technology is not growing so fast in China, and there are many difficulties to be overcome. Under this situation, this paper puts forward the concept of engine performanc e numerical concept design which is based on the relationships between vehicle performance target parameters and engine design and performance parameters.In this paper, all conclusions are based on the steady test results of four turbocharged gasoline engine. In this paper, firstly, the variation characteristic of the key parameters that affect the combustion process of gasoline engine such as air-fuel ratio, start point of combustion, 50% point of combustion, combustion d uration, etc., to identify the common law of key parameters which affect the combustion process mostly were found out. We can see that the gasoline engine combustion efficiency and its excess air ratio has a good linear relationship, at the same time, the combustion starting point, 50% point of combustion, combustion duration and other parameters will change when the speed and load of the gasoline engine changes, and generally increases when the load is increasing. And then, using the above law, the a rticle summarizes the required key boundary conditions for the next simulation process during the conceptual design of engine development.And then, this paper introduces the concept of engine performance numerical concept design which is based on the relationships between vehicle performance target parameters and engine design and performance parameters. And then establishes a one-dimensional standard modulus for the numerical simulation of the gasoline engine performance development process.Finally, the article uses the test data of a conventional gasoline engine to demonstrate the effectiveness of standard modulus. |
