Vortex tube heat booster to improve performance of heat driven cooling cycles.

Increasing energy costs justify research on how to improve utilization of low-grade energy that is abundantly available as solar energy or as waste heat from many thermodynamic processes. One option is to directly generate cooling through absorption/adsorption or vapor jet ejector cycles. As in the case of power generation cycles, cooling cycle efficiencies would increase if the heat input were available at higher temperature. This paper assesses the feasibility of a novel idea that uses a vortex tube to increase the available temperature levels of low-grade heat sources. The desired temperature increase is achieved by sending a stream of vapor that was heated by the waste heat source through a vortex tube, which further elevates the temperature used in a heat driven ejector cooling cycle. Simulation results show that COP can be increased by 12% with the use of the vortex tube heat booster when the cycle is operating with low entrainment ratio at conditions where baseline performance and COP are low.

能源成本持续上涨，使得针对低品位能源利用效率提升的研究具备了充分的现实必要性——此类低品位能源来源广泛，涵盖太阳能以及诸多热力学过程所产生的废热。其中一种可行方案是通过吸收/吸附式循环或蒸汽喷射式引射循环直接制取冷量。与发电循环的原理一致，若输入冷却循环的热量温度更高，循环效率便可得到提升。本文针对一项全新构想展开可行性评估：该构想借助涡流管（vortex tube）提升低品位热源的可用温度水平。其具体实现路径为，将经废热源加热后的蒸汽流导入涡流管，以此进一步提升热驱动引射式冷却循环所需的加热温度。仿真结果表明：当循环在低引射比工况下运行，且基线性能与性能系数（COP）处于较低水平时，加装涡流管式热助推器可使COP提升12%。