Design of split cooling of national engine with two thermostats

Due to the global tendency to use downsized engine with higher output power and the legal requirements imposed on pollutants, causes using of new technology in design of IC engines. A new economical method is using of a separate cooling system with two thermostats. In this research entering of coolant to block and cylinder-head carry out separately with two different volumetric flow rate and two thermostats with different performance temperature. In this survey, after benchmarking of cooling circuit of new engines, design and performance of EF7 engine with dual circuit cooling passage was investigated. For this aim, two subset of GT-SUITE are coupled for simulation of cooling passage of national engine. For this purpose, first the engine cooling-circuit is simulated in GT-COOL and coupled with GT-POWER performance circuit in NEDC cycle. Validation of results have been carried out with experimental data of the coolant temperature. Then, the effect of the separate cooling-circuit of the block and cylinder-head using two thermostats on the warm-up time and hot spot temperature in cylinder-head have studied. Results show 11 percent decrease in warm-up time