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.
Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .