Efficiency at Maximum Power of Endoreversible Quantum Otto Engine with Partial Thermalization in 3D Harmonic Potential

Abstract

We study partial thermalization to the efficiency of a quantum Otto engine using Bose-Einstein Condensation in potential harmonic 3D. Partial thermalization occurs at finite-time isochoric process, preventing the medium from achieving equilibrium with reservoirs, leaving it in a state of residual coherence. Under these circumstances, the performance of the engine can be seen from its power and efficiency at maximum power (EMP). The 3D harmonic potential is used to generate an excitation of energy during the expansion and compression. The sum of all this energy is defined by the total work done in a cycle. Using Fourier’s law in conduction, we found that power explicitly depends on the duration of heating and cooling stroke time and efficiency of the engine; that is the higher stroke time and efficiency, the less power output. In order to find an optimum efficiency (EMP), we maximize power with respect to compression ratio , and we found that EMP also depends on the isochoric heating and cooling process. By varying the duration of the isochoric process, EMP slightly decreases with increasing time due to entropy production. However, setting the cooling stroke time more extended than the heating stroke time could significantly improve EMP.