Entransy dissipation minimization for optimization of heat exchanger design

Abstract

In this paper, by taking the water-water balanced counterflow heat exchanger as an example, the entransy dissipation theory is applied to optimizing the design of heat exchangers. Under certain conditions, the optimal duct aspect ratio is determined analytically. When the heat transfer area or the duct volume is fixed, analytical expressions of the optimal mass velocity and the minimal entransy dissipation rate are obtained. These results show that to reduce the irreversible dissipation in heat exchangers, the heat exchange area should be enlarged as much as possible, while the mass velocity should be reduced as low as possible. entransy, heat exchanger, optimization design Citation:Li X F, Guo J F, Xu M T, et al. Entransy dissipation minimization for optimization of heat exchanger design.

Analysis of condenser shell side pressure drop based on the mechanical energy loss

“…Then, Guo et al [11] proposed the extremum entransy dissipation principle for optimizing heat transfer processes where the extremum entransy dissipation corresponds to the optimal heat transfer performance when a thermodynamic cycle is not involved. This new principle has been applied to optimizing heat conduction [11][12][13][14][15][16][17][18][19], convective heat transfer [20][21][22][23], thermal radiation [24] processes and the heat transfer in heat exchanger [25][26][27][28][29][30][31][32][33], with all the studies confirming that the optimal results can be obtained based on the extremum entransy dissipation principle.…”

Recent progress on renewable energy in engineering thermophysics

“…For example, Guo et al [78] put forward a concept of entransy, which can be the central physical quantity characterizing heat transfer processes not related to heat-to-work conversions, and there are many relative interesting works that have been done [79][80][81]. …”

Entransy Dissipation Theory and Its Application in Heat Transfer

“…In this section our work , Li et al 2011) is reviewed. In this work, a dimensionless method of the entransy dissipation of the heat exchanger is established.…”

“…examined the validity of the entransy dissipation number as the performance evaluation criterion of heat exchanger. Furthermore, for the water-water balanced counter-flow heat exchanger Li et al (2011) took as the minimum overall entransy dissipation number as an objective function, under certain assumptions it was proved that there is a corresponding optimum in duct aspect ratio or mass velocity since the variation in the duct aspect ratio or mass velocity has opposing effects on the two types of entransy dissipations caused by heat conduction under finite temperature difference and the flow friction under finite pressure drop, respectively. We also develop analytically expressions for the optimal duct aspect ratio and mass velocity of a heat exchanger that are useful for design optimization.…”