Abstract
KEYWORDS – Exhaust heat recovery, Heavy duty vehicles, Piston expander, Tests, Simulation
ABSTRACT –
Nearly 30 percent of the fuel energy in an internal combustion engine is lost as waste heat in the form of hot exhaust gases. Nowadays it seems clear that the heavy duty manufacturers will implement bottoming Rankine cycles to recover the exhaust heat on their long haul trucks in the 2020s as an answer to future stringent regulations and the still increasing customer pressure for reductions in operating cost. This would provide 3 to 5% fuel economy on heavy duties. The Exoès Company has developed a swashplate expander working with ethanol or refrigerant vapors for Rankine cycles. A prototype has been built as well as a test bench that can reproduce the hot source and cold sink available in a truck. The performance tests of the prototype took place in 2015. A refined 1D Matlab physical model has been coded and calibrated to point out the different efficiency losses. In this paper, we present the expander technology, the test results, the expander model and its calibration.