Analysis of the effect of using variable speed electric water pump on the engine cooling system of a passenger car

In this article, the effect of the usage of variable speed electric water pump on the cooling system of a type of passenger car engine has been investigated. The engine water circulation in most of today s cars uses a mechanical method, the power required for its circulation is provided by a belt with a ratio of 1:1 from the crankshaft. This action makes the changes of the water pump speed a function of the engine speed and there is no control over it. One way to solve this problem is to use an intelligent thermal management system. In this method, some components of the cooling system, including the electric water pump, are controlled based on the working conditions and engine temperature. In this research, GT Suite and Simulink software were used simultaneously, and for this purpose, the engine cooling circuit with a mechanical water pump was simulated in GT Suite software and the accuracy of laboratory values was verified in terms of heat transfer. Then the mechanical connection of the water pump was disconnected and the water pump circuit was controlled with an electric motor. In the next step, in order to obtain the control pattern, the electric water pump was replaced with the mechanical water pump in the simulation pattern. The results of the software and experimental simulations of the intelligent cooling system showed a 13.4% reduction in engine warm-up time. To avoid large changes in the electrical water pump speed, the electric water pump speed equal to 100 rpm (13.4% difference) can be fast time to reach the normal temperature. Also engine speed of 300 rpm (3.2% difference) can be the closest to the mechanical water pump to cool the engine with this new model, to be followed at speeds below 1000 rpm.