The Numerical Simulation Of Flow And Temperature Field In Cylinder Head Of Diesel Engine With Small Cylinder Bore

The cylinder head is a much complex composition of internal combustion engine. Its working environment is very tough and it has to bear hard pressure developed by heat stress, resulting in crack.Nowadays, flow in cooling system and heat transfer is the key problem studied by scholars currently. At the same time, the flow in cooling system will affect the distribution of heat and then dominate the values of heat stress.The methods used to study the cooling system in cylinder head can be divided two parts: one is to use experiment equipment to measure data, the other is to use CFD technology. Using the experiment equipment to measure data is very hard for the CFD engineers to complete their task and the data offered by the experiment equipment is not accurate in some times, because of the complex structure in cylinder head.Comparing with experiment, CFD technology is more convenient, moreover, in most case, the result offered by the CFD analysis is content. Accompanied by computer technology developing, the result acquired from CFD analysis is becoming more and more reliable. Because CFD technology is a cheap,short-cycle and flexible method, so it is playing a key role in the field of studying cylinder head and become one of the most important method .The flow in cooling system and heat transfer in the cylinder head is studied by CFD numerical technology in this paper. The cylinder heads studied in this paper can be divided two types: one is four cylinders head with two valves and the other is four cylinders head with four valves. For four cylinders head with two valves, two cooling jackets with different inlet structures, called cooling jacket with spiral inlets and cooling jacket with tangential inlets, are studied in this paper. The flow characters of the two cooling jackets are comparatively analyzed without considering the heat transfer affection. By the same token, the flow characters of cooling jacket of four cylinders head with two valves and four cylinders head with four valves are comparatively studied in this paper. At last, total model for four cylinders head with four valves are completed by solid/fluid interaction technology and the distribution of heat transfer in this total model is deliberately studied.Through comparatively analysis of flow in cooling jackets with different structures and distribution of heat transfer in total model for four cylinders head with four valves, it fully offers the character of the flow in cooling jacket with different structures and the distribution of heat transfer in four cylinders head with four valves, furthermore, this paper describers their advantage and disadvantage, which can be used as the references for manufacture and design.