同轴换热器内流动与换热的实验研究

Study on Heat Transfer and Pressure Drop of Coaxial Spiral Tube to Tube Heat Exchanger

采用实验的方法以水为介质研究了同轴换热器内的流动与传热,Re为3×104～10×104.对具有不同螺距两根内管管内的摩擦阻力及同轴换热器整体换热性能进行了实验研究,研究表明:管内摩擦自力系数是相同情况下圆管的3～3.5倍.采用数值计算的方法揭示了同轴换热器管内外流场特征.

Experiment methods using water as medium was adopled to study the flow and heat transfer in coaxial spiral tube to tube heat exchanger with Reynolds range from 30 000 to 100 000, and experiment research was carried out on two tubes with different helical pitch for their frictional resistance and heat transfer performance. The study shows that the tube frictional resistance coeffi- cient of coaxial spiral tube to tube heat exchanger is 3 to 3.5 times as large as circular tube ex- changer. The flow field characteristics outside and inside the coaxial spiral tube to tube heat ex- changer tubes are revealed using numerical methods.