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对等热流边界条件下速度场与温度场同时发展的进口段效应,进行了理论研究和实验研究。在理论研究中,基于求解传热问题三大方程组,推导出可借助有限差分法求解的微分—积分方程组,编出了计算机计算程序。根据数值解,得到了一些湍流传热计算关系式。对于速度场与温度场同时发展工况: L_h/D_e=Pe/(1+6.0PrRe~(0.545) Nu(x)=(1.80+0.017Pe~(0.8)((X/D_e)/(L_h/D_e)-ln(X/D_e)/(L_h/D_e))+2.6+0.002Pe~(0.8) 对于速度场充分发展,只温度场正在发展工况: L_h/D_e=Pe/(1+5.9PrRe~(0.554) Nu(x)=(1.83+0.015Pe~(0.8)((X/D_e)/(L_h/D_e)-ln(X/D_e)/(L_h/D_e))2.57+0.004Pe~(0.8) 对于稳定段: Pu(∞)=4.4+0.019Pe~(0.8) 在实验研究中,环形通道实验段内径d_1=12.34mm,外径d_2=19.00mm,通道外壁绝热,内壁施以恒热流。研究表明,数定值与实验结果以及其他作者实验结果吻合良好。研究参数范围:Re=2×10~4～1.35×10~5;Pe=128～854。
The theoretical and experimental studies on the inlet section effect of simultaneous development of velocity field and temperature field under the condition of equal heat flow boundary are carried out. In the theoretical study, based on the three equations solving the heat transfer problem, the differential-integral equations solved by finite difference method are deduced, and the computer program is compiled. According to the numerical solution, some turbulent heat transfer calculation equations are obtained. For the simultaneous development of the velocity field and the temperature field: L_h / D_e = Pe / (1 + 6.0PrRe ~ (0.545) Nu (x) = (1.80 + 0.017Pe ~ (0.8) (X / D_e) / (L_h / For the full development of the velocity field, only the temperature field is under development: L_h / D_e = Pe / (1 + 5.9PrRe (D_e) -1n (X / D_e) / (L_h / D_e)) + 2.6 + 0.002Pe ~ (0.554) Nu (x) = (1.83 + 0.015Pe ~ (0.8) ((X / D_e) / (L_h / D_e) -ln (X / D_e) / (L_h / D_e)) 2.57 + 0.004Pe ~ 0.8) For the stable section: Pu (∞) = 4.4 + 0.019Pe ~ (0.8) In the experimental study, the inner diameter d_1 = 12.34mm and the outer diameter d_2 = 19.00mm, The results show that the numerical results are in good agreement with the experimental results and the experimental results of other authors. The range of the research parameters is Re = 2 × 10 ~ 4 ~ 1.35 × 10 ~ 5 and Pe = 128 ~ 854.