Design, simulation, and test results of a heat-assisted three-cylinder Stirling heat pump (C-3)

This paper describes recent results in a project at KUBOTA to develop a gas engine-driven Stirling heat pump using both engine shaft power and engine exhaust heat source. The design, simulation and test results of the third prototype three-cylinder machine (C-3) are presented. The three-cylinder machine is modeled as a combination of two Stirling sub-systems, one a power producer and one a heat pump. These have been separately optimized then joined into the three-cylinder heat-assisted heat pump case. Shaft power is augmented by thermal power. Performance is effectively controlled by the phase shifting of the third piston to adjust the absorbing of thermal power. The test results of the C-3 prototype machine are given and are shown to compare well with predictions made in the Sage simulation code.