Cummins Inc.
Systems and methods for waste heat recovery for internal combustion engines

Abstract:

A waste heat recovery system comprises an exhaust system, a thermal oil circuit, and a Rankine cycle circuit. The exhaust system is configured to provide exhaust gases. The thermal oil circuit comprises a first heat exchanger and a second heat exchanger. The first heat exchanger is positioned along the exhaust system. The first heat exchanger receives heat from exhaust gases and separately receives thermal oil such that heat from exhaust gases is transferred to thermal oil within the first heat exchanger. The second heat exchanger receives thermal oil from the first heat exchanger and provides thermal oil to the first heat exchanger. The Rankine cycle circuit circulates working fluid through the second heat exchanger separate from thermal oil such that heat from thermal oil is transferred to working fluid within the second heat exchanger. An expander utilizes heat within working fluid to produce mechanical energy.