论文部分内容阅读
制造和使用现代强化柴油机的经验表明,为提高排气阀与气缸盖的可靠性和使用寿命,必须进一步改进结构以降低热应力。在使用数学模拟温度场与热应力的方法时,这些工作的有效性就颇为明显了。大家知道,在计算任何热负荷零件的应力之前,都必须计算温度场,而温度场的精确度又主要取决于所规定的热交换边界条件的可靠性。在模拟气阀与气缸盖的固定温度场时,确定边界条件的麻烦之处是这些零件有一些表面在工
The experience with manufacturing and using modern enhanced diesel engines has shown that in order to increase the reliability and service life of the exhaust valve and cylinder head cover, the structure must be further improved to reduce the thermal stress. The effectiveness of these efforts is evident when using mathematical methods that simulate temperature fields and thermal stresses. As you know, the temperature field must be calculated prior to calculating the stress of any heat-loaded part, and the accuracy of the temperature field depends primarily on the reliability of the specified heat exchange boundary conditions. The hassle of determining the boundary conditions when simulating the fixed temperature field of a gas valve and cylinder head is that some of these parts have a working surface