基于(火用)分析的流动工况及强化传热方式的选择

本文建立了无因次火用损失率的方程，并由此求解了空气、水、油三种典型工质的管内流动与换热的最佳雷诺数和最小火用损失率。结果表明，水、空气的最佳流动工况为湍流，而油的最佳流动工况为层流。同时，还用火用损失率表达式求解了内插扭带管、螺旋槽管两种不同管型中水的最佳雷诺数和最小火用损失率。结果表明，对于水宜选择螺旋槽的强化传热方式。

CHOICE OF FLOW OPERATING MODES AND ENHANCED HEAT TRANSFER SURFACES BASED ON THE ENTROPY ANALYSIS

In this paper,the dimensionless equation of entropy loss was established. From this equation,the optimum Reynolds numbers and minimum entropy loss of pipe flow with heat exchanging of three typical fluids,air water and oil,was solved The result shows that the optimum flow operating modes of air is turbulence,while that of oil is laminar.The optimum Reynolds number and minimum entropy loss of two pipes flow with different enhanced heat transter surface,pipes with plug in twist belt and pipes with helix slot,was gotten. The result indicates that the helix slot pipe is suitable for water.