Authors

Simulation of evaporation and condensation processes into the channels of regenerative heat exchangers

DOI: 10.21047/1606-4313-2016-15-1-82-85
UDC 628.84

Simulation of evaporation and condensation processes into the channels of regenerative heat exchangers

Tsygankov A.V., Aleshin A.E.

Abstract
Physical processes of evaporation and condensation in microchannels of heat exchangers influence heat exchange between supply and exhaust air. The main idea of this article is to show approach to solve problems of evaporation and condensation simulation with the use of CFD. It is liquid-gas boundary inside the channel which is the main focus of the research. Evaporation is calculated with the use of diffusion model: vapor on surface is considered to be saturated and diffusion is motion force. Air is supposed to consist of two parts: dry air and vapor. The model of ideal gas is used to describe mixture conditions. The features of simplifications used, based on channel sizes, temperature range and thermal properties of solid part of heat exchanger, are described. Initial and boundary conditions of computer model and volumetric mesh peculiarities are given.Tthe idea of the advantages and disadvantages of simplified model becomes clear. The article explains an approach to evaporation and condensation simulation for engineering cases.

Keywords: computational fluid dynamics, evaporation, condensation, heat recovery, simulation, regeneration systems, phase transition

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