Search Results

This paper presents performance of a novel ECCS (electricity-cooling cogeneration system) based on cascade utilization of the waste heat of marine engines. The cogeneration system consists of a steam Rankine cycle and an NH3-H2O absorption refrigeration cycle with an expander. The steam Rankine cycle recycles the energy of both jacket coolant and exhaust gas of engine, while the absorption refrigeration cycle is employed to recover energy of the expanded steam at the turbine outlet in Rankine cycle. The performance of the waste heat recovery system is evaluated in terms of electricity, cooling capacity, equivalent electricity and exergy efficiency. The simulation results show that the novel ECCS exhibited a maximum net electricity output of 4561 kW, a maximum cooling capacity of 3197 kW, and a maximum equivalent electricity of 5233 kW.

Cogeneration system has become a valuable alternative approach for cascade waste heat recovery (WHR). In this paper, a novel electricity-cooling cogeneration system (ECCS) based on organic Rankine cycle-absorption refrigeration cycle (ORC-ARC) combined system is proposed to recover the waste heat of marine engine. ORC was adopted in the higher temperature cycle, in which alternatives D4, MDM and MM were selected as the working fluids. An ARC was adopted in the lower temperature cycle to recover the heat of the working fluid at the regenerator outlet in ORC. It aims to satisfy refrigeration requirement aboard ship, in which a binary solution of ammonia-water is used as the working pairs. Electricity output, cooling capacity, total exergy output, primary energy ratio (PER) and exergy efficiency are chosen as the objective functions.

This paper presents a model system TEG-DORC that employs thermoelectric generator (TEG) as a topping cycle integrated with a dual-loop organic Rankine bottoming cycle (DORC) to recover exhaust heat of internal combustion engine (ICE). The thermodynamic performance of TEG-DORC system is analyzed based on the first and second law of thermodynamics when system net output power Wnet, thermal efficiency ηth, exergy efficiency ηe and volumetric expansion ratio are chosen as objective functions. The model has many parameters that affect combined system performance such as TEG scale, evaporation pressure of high temperature ORC loop (HT loop) Pevp,HT, condensation temperature of HT loop Tcond,HT. It is suggested that HT loop has a vital influence on system performance.