Maximum entropy generation rate in a heat exchanger at constant inlet parameters

• Autorzy: Laskowski R. , Jaworski M.
• Języki publikacji: EN

Abstrakty

EN

The main goal of the paper is to provide a condition for which a maximum entropy generation occurs in a heat exchanger at constant inlet parameters (temperatures and mass flow rates). Knowing this condition is essential during the design of the heat exchanger as it allows designers to avoid one of its most unfavourable operating conditions in terms of thermodynamics. Entropy generation resulting from the resistance of heat-transferring fluids to flow was not taken into account. Entropy generation was analysed as a function of a heat flow rate at constant parameters at the inlet of a condenser and a counter-flow double-pipe heat exchanger. The analysis showed that for the condenser the entropy generation rate increases with the increase in the heat flow rate. The maximum entropy generation rate occurs for the maximum flow rate of the heat that can be transferred according to the definition of heat transfer effectiveness. For the counter-flow heat exchanger, the entropy generation as a function of the heat flow rate reaches maximum at constant inlet parameters (temperatures and mass flow rates). It appeared that the peak entropy generation, or the largest exergy loss, occurs when the outlet temperatures of the fluids are equal. This assertion was verified against data obtained from a simulator of the counter-flow heat exchanger for two different relations between heat capacity rates.

Słowa kluczowe

EN

maximum entropy generation rate; entropy; heat exchanger

PL

maksymalna szybkość generowania entropii; entropia; wymiennik ciepła

• Wydawca: Wydawnictwo Uczelniane Politechniki Koszalińskiej
• Czasopismo: Journal of Mechanical and Energy Engineering
• Rocznik: 2017
• Tom: Vol. 1, No 1
• Strony: 79--86
• Opis fizyczny: Bibliogr. 32 poz., wykr.

Twórcy

autor

Laskowski R.

• Institute of Heat Engineering, 21/25 Nowowiejska Str., 00-665, Warsaw, Poland

autor

Jaworski M.

• Institute of Heat Engineering, 21/25 Nowowiejska Str., 00-665, Warsaw, Poland

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Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).