Investigating the process of warming up an engine after starting in cold weather

Abstract

There was studied the process of changing the state of an engine, and the laws of heat transfer in the engine in acceleration-rundown mode in cold weather. Search experiments on studying the effects of engine warming-up modes under different conditions after starting for warming-up time were performed. The study was conducted on the petrol engine ZMZ-406 with distributed fuel injection. There is given a mathematical model of warming-up times after starting in cold weather depending on ambient temperatures, on temperature of the engine before warming-up represented by cooling liquid temperature, on rotary speed of the crankshaft. The variation levels of these factors were determined. All of them are important, and have a significant impact on the response function. The analysis of experimental data is presented in the form of a second-order regression equation. According to the model, response surfaces were built to visually assess an impact of one or other parameter on changing the total warming-up time. It has been experimentally found that the total warming-up time is mostly influenced by rotary speed of the crankshaft. The coolant temperature has a significant impact, too, and the ambient temperature has the least impact. There is given an assessment of this method for warming up the petrol engine in cold weather.