승용디젤엔진용 배기일체형 실린더헤드 개발

The passage of exhaust gasses from the exhaust valve to the turbocharger inlet has exhaust ports and manifolds. In a passenger car diesel engine, exhaust manifolds which need high thermal resistance are generally made of stainless steel. But the integrated cylinder head does not need exhaust manifolds because ports and manifolds have already integrated. So the thtal weight of engine could be diminished as a result. In this study, both of the flow coefficients of integrated exhaust ports and coolant flow in cylinder head are optimized by using commercial CFD code. The design factors of integrated exhaust ports are short turn radius, dividing wall length and area of confluence region, these factors are optimized by using DFSS for improving flow coefficient and deviation. The flow coefficient is improved up to 2.4% in comparison with original model. The deviation in flow coefficient among cylinders is within 2.5%. The calculated mean flow rate around exhaust valve bridges among every cylinder is 8.14lpm, this figure is improved up to 44% compared to that of original model.