Calculation of flow parameters for coaxial heat pipes and determination of their isothermality characteristics

In the production of materials by melting and growth processes it is important that temperature in isothermal volumes be maintained at a constant level in the range 900-1200 K with fluctuations not exceeding a few tenths of a degree. This can be successfully achieved by using high-temperature coaxial heat pipes. Here, a mathematical model is developed which describes heat and mass transfer processes in the vapor channel of coaxial heat pipes. Isothermality characteristics are calculated for a coaxial sodium heat pipe.