1D simulation analysis and optimization design of engine cooling system

Abstract

The engine cooling system takes away the heat absorbed by high-temperature parts during the operation of the car engine in a timely manner, keeping it working within the normal temperature range. This article applies Flowmaster software to establish a one-dimensional cooling system model for a certain model of National Five diesel engine. Relevant boundary conditions are inputted to complete steady-state simulation calculations of the system under different operating conditions, obtaining the flow rate, pressure distribution, and temperature rise of each component. At the same time, three optimization schemes are designed based on the original cooling system to predict and evaluate the working capacity of the cooling system, Based on the calculation and analysis results, improvement suggestions are proposed to guide the structural design and testing of the cooling system, greatly reducing research and development time and reducing research and development costs. The calculation results show that the flow rate of each component in the rated point, heating test condition, and idle condition of the original plan has decreased compared to the flow rate of a certain four machine on the same platform under the same working condition (the air compressor flow rate is higher than the limit value), and the temperature difference of the radiator and heating flow rate do not meet the specification requirements. Suggest using Plan 3 to increase the water pump speed ratio to 1.25, with a warm air flow rate of 5.33L/min under idle conditions, which is 72% higher than the original plan and meets the vehicle limit requirements. In addition, to ensure the accuracy and reliability of the model and calculations, this project conducted cooling system tests on an engine bench. The comparison between the simulation calculation data and the experimental data showed that the simulation calculation results were consistent with the experimental results.