Liu, XiaoweiChen, LingenMeng, FankaiDing, Zemin2017-09-192017-09-192017http://hdl.handle.net/2263/62374Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .By considering quantum friction, heat resistance and heat leakage, this paper establishes a quantum Brayton heat pump model. The working substance is a two-level spin-1/2 system, and the cycle has four branches: two adiabatic branches and two isomagnetic branches. By using quantum thermodynamics and quantum master equation, this paper obtains heating load and COP of the pump. By using Euler-Lagrange method, this paper optimizes heating load and COP performance for two cases: the general case and the case at high temperature limit. Influences of quantum friction, duration of adiabatic process and heat leakage on the performance are further analyzed.7 pagesPDFenUniversity of PretoriaHeating loadCop optimisationIrreversible quantum brayton heat pumpSpin-1/2 systemsPresentation