The performance of absorption–compression hybrid refrigeration driven by waste heat and power from coach engine

• The absorption–compression hybrid refrigeration cycle was proposed.
• The exhaust gas parameters from vehicle engine were analyzed.
• The structure and heat transfer area of the main heat exchangers were confirmed.
• Heat transfer models of the hybrid refrigeration cycle were established.
• The performances of the hybrid refrigeration cycle were investigated.

Through quantitatively analyzing the waste heat from a vehicle engine under different running conditions and calculating the heat load of devices in the absorption–compression hybrid refrigeration cycle, the heat transfer area and structure of the main unit are determined. The distributed parameter model of heat transfer between the exhaust gases and working fluids in the generator, as well as the lumped parameter model in the other heat exchangers are established. The research results show that the absorption refrigeration sub-cycle can completely meet the space cooling demand (30 kW) for the coach when it runs over 100 km h−1. The compression refrigeration sub-cycle fully supplies the cooling load for the coach when speed is lower than 40 km h−1. Both the sub-cycles work together to supply the space cooling for the coach when speed is between 40 km h−1 and 100 km h−1. In addition, the COP of the absorption–compression hybrid refrigeration cycle decreases with the rise in ambient temperature.