不同目的热优化目标函数:热量传递势容损耗与熵产

热量传递势容(势容)反映了物体的导热能力,在导热过程中势容有损耗,对应于势容损耗最小的导热过程效率最高,传热速率最大。熵反映了过程的不可逆性,在导热过程中熵有增加(熵产),对应于熵产最小的过程是系统做有用功的能力((?))损失最小的过程。以势容损耗和熵产为目标函数,分别对导热平板和圆形导热管进行了导热优化计算。以势容损耗作为目标函数的优化,要求沿传热方向温度的梯度为常数,结果是系统具有最大的导热能力。以熵产作为目标函数的优化,要求沿传热方向温度的自然对数的梯度为常数,结果是系统具有最小的(?)损耗。

TWO DIFFERENT THERMAL OPTIMIZATION OBJECTIVE FUNCTIONS:DISSIPATION OF HEAT TRANSPORT POTENTIAL CAPACITY AND ENTROPY PRODUCTION

Heat Transport Potential Capacity (HTPC) represents a body's ability to transfer heat, which could be dissipated in heat transfer processes; the process with the least HTPC dissipation has the highest conduction efficiency and the maximum heat flux. While entropy represents the irreversibility of a process, which could be produced; the process with the least entropy production has the least exergy (available energy) destruction. In the present article, the dissipation of HTPC and entropy production being used as the objective function respectively, the heat conduction optimizations of planar plate and circular pipe were carried out, and the results were discussed and compared. In the both cases, when the dissipation of HTPC was used as the objective function, the optimization results is that the temperature gradient is uniform, and the system has the maximum heat flux. While the optimization results with the entropy production as objective function is that the gradient of natural logarithmic temperature is uniform, and the system has the least exergy destruction.