论文部分内容阅读
符号说明a 热扩散系数 m～2/sAi 以管子内径计算的传热面积 m～2A_o 以管子外径计算的传热面积 m～2A_m 以管子中径计算的传热面积 m～2C 常数C_p 流体的比热 kcal/(kg·℃)K_o 以A。计算的传热系数 kcal/(h·m～2·℃)m 指数n 指数Q 换热器的传热量 kcal/hR_i 管程流体温度边界层的对流传热热阻与传热过程总热阻之比R_o 壳程流体温度边界层的对流传热热阻与传热过程总热阻之比R_w 管壁导热热阻与传热过程总热阻之比t_(il) 管程流体的进口温度℃t_(ol) 壳程流体的进口温度℃V 管程或壳程流体的流量 m～2/hW_i 管程流体的流速 m/s
DESCRIPTION OF SYMBOLS a Thermal diffusivity m ~ 2 / sAi Heat transfer area in terms of tube inner diameter m ~ 2A_o Heat transfer area in tube outer diameter m ~ 2A_m Heat transfer area in tube center diameter m ~ 2C Constant C_p Specific heat kcal / (kg · ℃) K_o to A. Calculated heat transfer coefficient kcal / (h · m ~ 2 · ℃) m index n index Q heat exchanger heat transfer kcal / hR_i pipe fluid temperature Boundary layer convective heat transfer resistance and heat transfer process of total thermal resistance R_o Shell fluid temperature boundary layer convection heat transfer thermal resistance and heat transfer process than the total thermal resistance R_w thermal conductivity of the pipe wall thermal conductivity and the total heat transfer process than the thermal resistance t_ (il) pipe fluid inlet temperature ℃ t_ (ol) inlet temperature of shell fluid ℃ V flow of tube or shell fluid m ~ 2 / hW_i flow rate of tube fluid m / s