A steam-assisted Brayton air cycle (SBAC) is proposed for exhaust heat recovery (EHR) of internal combustion (IC) engine, which consists of a regenerated Brayton air cycle and an open Rankine steam cycle. The regenerated Brayton air cycle is coupled to IC engine exhaust pipe and used to directly recover IC engine exhaust heat. A steam generating plant is coupled to IC engine exhaust pipe behind the Brayton air cycle which uses IC engine exhaust heat to generate steam, and then the steam is injected into the power turbine of Brayton air cycle. I...