Abstract:
An optimal motion of a piston is examined. The piston is
fitted inside one cylinder, which contains ideal gas. The gas
contacts a heat bath and is heated with given rate f (t) in finite
time. The heat transfer between heat bath and gas obeys the
linear phenomenological heat transfer law (LPHTL)
1 q (T ) . Optimal expansion problem of the heated gas is
solved step by step. There exist an OMP for any given final
time, an optimal process duration of expansion (OPDE) for
maximum power output (MPO), and an OPDE for maximum
work output (MWO) for fixed power output. Both the OPDE
for MPO and the OPDE for MWO with fixed power output is
obtained. The best performance of the system is obtained using
finite time thermodynamics. Numerical calculations are
performed. The results show that the leaking energy and the
energy from the heat source change into work output of the
expansion process. Both the MPO and MWO with fixed power
increase with the increase of heat conductance K . The results
obtained can provide some guidelines for real systems
operating with LPHTL.
Description:
Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .
