The high temperature and high pressure fluid of the thermal system in the industrial production will release heat in the process of temperature and pressure reduction

resulting in waste of energy. This paper proposes a pressure reducing Tesla valve-tube heat storage device to recover waste heat. Four types of heat storage device models

including the basic

corrugated

transverse-corrugated and converging- diverging Tesla valve-tubes

are established. Based on the enthalpy-porous medium model to describe the phase change heat transfer process

the flow and heat transfer characteristics of each device during forward and reverse flow heat storage processes are investigated by numerical simulation under different inlet mass flow rates. The results show that the pressure reducing effect is enhanced significantly through improving the structural of Tesla-valve. When the inlet mass flow rate is 0.01 kg/s in the reverse flow heat storage process

compared with the original Tesla-valve

the total pressure drop in the transverse-corrugated Tesla-valves and the converging-diverging Tesla-valves increases by 73.01% and 133.13%

the average effective heat transfer coefficient increases by 13.27% and 15.31%

the exergy efficiency is improved marginally by 0.15% and 0.12%

respectively. This study can provide theoretical reference for the design and application of high performance Tesla-valve coupling the phase change heat storage device.