The method of obtaining the external characteristic curve of the engine

Abstract

The invention belongs to the field of matching design of an engine and a complete vehicle, and particularly relates to a method for obtaining an external characteristic curve of an engine, comprising the following steps: installing the engine to be tested on the vehicle for routine testing to obtain an actual acceleration curve; selecting and matching the parameters of the engine to be tested The similar known external characteristic data of the engine is used as the approximate curve; the approximate curve is discretized to obtain multiple first points; the multiple first points are brought into the one-dimensional simulation model to calculate the ideal acceleration curve; the ideal acceleration curve is compared with the actual acceleration curve , if the difference exceeds the set value M, adjust the position of the first point and repeat the calculation and comparison, if the difference is less than or equal to the set value M, output the optimized approximate curve as the external characteristic curve of the engine under test. The external characteristic parameters of the engine to be tested are obtained by means of numerical calculation through the conventional vehicle acceleration test curve, which avoids various shortcomings of measuring the external characteristic curve of the engine on the test bench.

Description

technical field [0001] The invention belongs to the field of engine and vehicle matching design, in particular to a method for obtaining an engine external characteristic curve. Background technique [0002] In the process of vehicle development, it is usually necessary to compare the vehicle with certain benchmark engines in order to develop a product that meets the target requirements. The external characteristic curve of the engine is one of the main characteristic parameters of the engine. It is not only used in the process of engine research and development, but also in the process of vehicle matching, in order to obtain better vehicle power and economic performance. Parameters are used as input for benchmarking analysis. However, from the perspective of technical protection, neither the engine development unit nor the vehicle manufacturer using the product will disclose such parameters of their respective engines, and this parameter is difficult to measure on the test...

AI Technical Summary

Problems solved by technology

However, from the perspective of technical protection, neither the engine development unit nor the vehicle manufacturer using this product will disclose such parameters of their respective engines, and this parameter is difficult to measure on the test bench, and the cost is high

Images