Showing 1 - 10 of 59
In the present work, a waste heat power generation system is analyzed based on the criteria with and without considering the heat/exergy loss to the environment. For the criteria without considering the heat/exergy loss to the environment, the first- and second-law efficiencies display different...
Persistent link: https://www.econbiz.de/10010811283
The viscous dissipation effect on the thermodynamic performance of the curved square microchannels in laminar flow is numerically investigated. The classical Navier–Stokes equations are adopted; aniline and ethylene glycol are selected as the working fluids. The results show that the heat...
Persistent link: https://www.econbiz.de/10010811378
The performance of an Isopropanol–Acetone–Hydrogen (IAH) chemical heat pump system is investigated in terms of enthalpy efficiency (COP) and exergy efficiency, in which the exothermic and endothermic reactions take place in the gas phase. The increase of reflux ratio, temperature of...
Persistent link: https://www.econbiz.de/10010576321
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In the present work, the entransy and entransy dissipation are defined from the thermodynamic point of view. It is shown that the entransy is a state variable and can be employed to describe the second law of thermodynamics. For heat conduction, a principle of minimum entransy dissipation is...
Persistent link: https://www.econbiz.de/10010808543
A variational principle for heat conduction is formulated which results in the steady state heat conduction equation established from the Fourier law. Furthermore based on the thermodynamics in terms of entransy a more general functional is defined for incompressible fluids. We show that...
Persistent link: https://www.econbiz.de/10010809304
Based on the entransy dissipation theory, the multi-parameter optimization design of recuperator is conducted in an Isopropanol–Acetone–Hydrogen (IAH) chemical heat pump system. The performance of the heat pump system can be improved significantly through the multi-parameter optimization,...
Persistent link: https://www.econbiz.de/10010808310
In the present work, a multi-parameter optimization approach of Isopropanol–Acetone–Hydrogen (IAH) chemical heat pump is developed based on the entransy theory. In the optimization process, the total low-temperature heat consumed by the heat pump system generally decreases while the...
Persistent link: https://www.econbiz.de/10010810616
A multi-objective optimization of main heat exchanger in a regenerative Brayton cycle system is carried out based on entransy dissipation. The best trade-off between the entransy dissipation numbers caused by heat transfer and fluid friction is achieved in the Pareto optimal solutions, the...
Persistent link: https://www.econbiz.de/10010811196
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