螺旋管内超临界航空煤油流动阻力特性

研究了系统压力、质量流速及螺旋管结构形式对超临界压力下航空煤油RP-3在螺旋管内的流动阻力特性.实验结果表明:螺旋管局部阻力系数变化曲线由螺旋管内流体临界雷诺数、拟临界温度分为明显的3个部分:工质温度低于拟临界温度且管内雷诺数小于螺旋管临界雷诺数时,局部损失系 数与雷诺数和螺旋直径与管径比D/d_in相关;流体温度低于拟临界温度且雷诺数大于临界雷诺数时,局部阻力系数只与D/d_in相关; 流体温度大于拟临界温度时,局部阻力系数除与雷诺数和D/d_in相关外,同时还与密度、黏性的大幅变化相关.另外,基于实验结果,提出了一种用压力、温度和螺旋直径与管径比进行修正的局部阻力系数关联式,拟合结果与实验结果相比,具有较好的一致性. 

Flow resistance characteristics of supercritical aviation kerosene in helix tube

Based on the experimental results,the effects of pressure,mass flow rate and style of helix tubes on the flow resistance characteristics were analyzed,and the flowing characteristics of aviation kerosene at supercritical pressure flowing through a helix tube were investigated .The results show that:the variation curve of local resistance coefficient was divided into 3 parts by critical Reynolds number and pseudo-critical temperature.Below the pseudo-critical temperature and Reynolds number,the local resistance coefficient was related to Regnolds number and D/d_in;below the pseudo-critical temperature and above the critical Reynolds number,it was just related to D/d_in;above the pseudo-critical temperature,it was not only related to Regnolds number and D/d_in,but also to huge variation of density and viscosity.Furthermore,a relational formula was proposed to predict the coefficient of local resistance with pressure,temperature and ratio of screw diameter versus inlet diameter when hydrocarbon fuel flowed through the helix tube at supercritical pressure.