屈服假塑性流体管流流动及传热规律研究

Research on Flow and Heat Transfer Law for Pipe Flow of Yield Pseudoplastic Fluid

结合屈服假塑性流体的本构方程、管流力平衡关系式以及非牛顿流体的能量方程 ,得出了屈服假塑性流体管流速度分布及温度分布。研究结果表明 :由于屈服应力的作用 ,管中心存在柱塞流动 ,柱塞的半径与屈服应力成正比 ,与压力梯度成反比 ;管流流量随屈服应力的增大而减小 ;柱塞内温度一致 ,从柱塞边界到管壁 ,温度逐渐减小 ,而且越靠近管壁 。

Combining the constitut ive equa tion of yield pseudoplastic fluid with t he force balance relation for pipe flow and the energy equation of non-Newtonian fluid,the velocity and temperature prof iles for pipe flow of yield pseudoplasti c fluid are obtained.The results show th at there is plunger-cylinder flow in the center of the pipe because of yield str ess.The radius in the lunger-cylinder is in direct proportion to yield stress and i nverse proportion to pressure gradient.T he flow rate of pipe flow decreases with increasing yield stress.The temperature in the plunger-cylinder is identical,an d fr om the boundary of plunger-cylinder to t he pipe wall,the temperature gradually d ecreases.Furthermore,the nearer to the p ip e wall,the larger the temperature drop g radient is.