Showing 1 - 10 of 235
Organic Rankine Cycle (ORC) could be used to recover low-grade waste heat. When a vehicle is running, the engine exhaust gas states have a wide range of variance. Defining the operational conditions of the ORC that achieve the maximum utilization of waste heat is important. In this paper the...
Persistent link: https://www.econbiz.de/10010808792
A theoretical formula is proposed to calculate the OET (optimal evaporation temperature) of subcritical ORC (organic Rankine cycle) based on thermodynamic theory when the net power output is selected as the objective function. The OETs of 22 working fluids including wet, isentropic and dry...
Persistent link: https://www.econbiz.de/10010809847
In recent years, more and more attention has been paid to organic Rankine cycle (ORC), which is simply structured, highly reliable and easily maintainable. In order to improve the efficiency of ORC systems, zeotropic mixtures whose phase change process is variable temperature, are used as...
Persistent link: https://www.econbiz.de/10010906291
A supercritical Rankine cycle using zeotropic mixture working fluids for the conversion of low-grade heat into power is proposed and analyzed in this paper. Unlike a conventional organic Rankine cycle, a supercritical Rankine cycle does not go through the two-phase region during the heating...
Persistent link: https://www.econbiz.de/10011053197
This study evaluates the vehicle exhaust WHR (waste heat recovery) potential using a RC (Rankine cycle ). To this end, both a RC thermodynamic model and a heat exchanger model have been developed. Both models use as input, experimental data obtained from a vehicle tested on a chassis...
Persistent link: https://www.econbiz.de/10011053645
An Organic Rankine Cycle for diesel engine waste heat recovery is modeled and optimized. The design parameters are nominal capacity of diesel engine, diesel operating partial load, evaporator pressure, condenser pressure and refrigerant mass flow rate. In addition four refrigerants including...
Persistent link: https://www.econbiz.de/10010809924
The selection of working fluid and working conditions of the Organic Rankine Cycle (ORC) has a great effect on the system operation, and its energy efficiency and impact on the environment. The main purpose of this study is to develop a procedure to compare capabilities of working fluids when...
Persistent link: https://www.econbiz.de/10010803951
HFO−1234yf is a new refrigerant with a nearly zero global warming potential (GWP) and ozone depletion potential (ODP); it exhibits thermodynamic properties similar to HFC−134a. The potential of HFO−1234yf as a working fluid for organic Rankine cycles (ORC) is elucidated through a...
Persistent link: https://www.econbiz.de/10011043997
The paper presented a working fluid selection and parametric optimization using a multi-objective optimization model by simulated annealing algorithm. The screening criteria considered included heat exchanger area per unit power output (A/Wnet) and heat recovery efficiency (Ф). The independent...
Persistent link: https://www.econbiz.de/10011053306
A fin-and-tube evaporator can be used for an ORC (organic Rankine cycle) to collect waste heat of the exhaust gas of an internal combustion engine. In this paper, the thermal-hydraulic characteristics of an ORC evaporator are analyzed using a CFD method. A 3D numerical model is derived from an...
Persistent link: https://www.econbiz.de/10011209457