A New Combined Thermodynamic Cycle for Waste Heat Recovery of Vehicle Engine

From the characteristics of waste heat in exhaust,cooling water and lubricant,a new thermodynamic cycle for waste heat recovery of vehicle engines was proposed. The present system consists of two cycles,organic Rankine cycle (ORC) for recovering the waste heat in high-temperature exhaust and lubricant and Kalina cycle for recovering the waste heat in low-temperature cooling water. Based on P-R equation of state,the thermodynamic performance of the cycle was theoretically calculated with a self-written computing program. Then the overall performance of the cycle with different organic working fluids was analyzed individually. Compared with the conventional cycle configuration used for only recovering the exhaust heat,the present cycle has higher waste heat recovery efficiency. The overall efficiency of the cycle with cyclopentane and R113 is 20.83% and 16.51%,respectively.