slovenski

Entropijska analiza sotočnih prenosnikov toplote

The entropy generation in a parallel-flow recuperative heat exchanger is analysed in this paper. During the operation of a heat exchanger, generally two sources of entropy generation normally exist: the pressure drop (friction) source and the heat-exchange source. Here, only the heat-exchange source is considered. The analysis is performed using an analytical mathematical model and the same non-dimensional numbers that were introduced into the energy analysis of heat exchangers by Bošnjaković, many years ago. The influence of the individual non-dimensional variables (the operating points of the parallel-flow heat exchanger) on the entropy generation is quantified. The results are presented non-dimensionally in diagrams, which gives them a more universal meaning. Special conditions, i.e. the boundary operating conditions, of the parallel-flow recuperator, which are identical to those for counter-flow and cross-flow exchangers, are also discussed.

prenosnik toplote; povečanje entropije; učinkovitost; reštive analitične

nije evidentirano

engleski

Entropy Analysis of Parallel-Flow Heat Exchangers

The entropy generation in a parallel-flow recuperative heat exchanger is analysed in this paper. During the operation of a heat exchanger, generally two sources of entropy generation normally exist: the pressure drop (friction) source and the heat-exchange source. Here, only the heat-exchange source is considered. The analysis is performed using an analytical mathematical model and the same non-dimensional numbers that were introduced into the energy analysis of heat exchangers by Bošnjaković, many years ago. The influence of the individual non-dimensional variables (the operating points of the parallel-flow heat exchanger) on the entropy generation is quantified. The results are presented non-dimensionally in diagrams, which gives them a more universal meaning. Special conditions, i.e. the boundary operating conditions, of the parallel-flow recuperator, which are identical to those for counter-flow and cross-flow exchangers, are also discussed.

heat exchangers; entropy generation; effectiveness; analytical solution

nije evidentirano