Analysis of the Second law of Thermodynamics in helical tubes with laminar flow subjected to the constant wall temperature

Helically coiled tubes are efficient heat transfer equipments due to their compact size and high heat transfer performance in comparison with straight tube counterparts. The performance of helically coiled tube with fully developed laminar flow and constant wall temperature has been investigated by calculating the entropy generation and the ratio of pumping power to heat transfer rate, analytically. Correlations have been used for Nusselt number and friction factor. The variation of the dimensionless entropy generation and pumping power to heat transfer rate ratio versus modified Stanton number and dimensionless temperature difference have been proposed according to the fact that the dimensionless entropy generation and pumping power to heat transfer rate ratio should be minimized to achieve an appropriate performance.

Keywords:

helically coiled tube , laminar flow , constant temperature , entropy generation