Numerical Investigation of Heat and Mass Transport and Surface Condensation due to Food Respıratıon and Transpıratıon in a Refrıgerated Space with Forced Convection

Year 2013, Volume: 16 Issue: 3, 115 - 122, 07.05.2013

Serdar Kocaturk , Nilufer Egrican

Abstract

Food load and air-flow area within a refrigerated space having one air inlet and one air outlet have been taken as two separate control volumes interacting with each other at their boundaries. In the lower control volume, stored vegetable products have been located and heat and mass transfer due to respiration and transpiration of these products have been modeled for determining boundary conditions of the upper control volume, in which heat and mass transport within the air circulation above the products have been modeled and numerically investigated. Upper surface temperature of the said upper control volume has been compared with the dew point temperature, and condensation heat and mass fluxes through the surface have been taken as upper boundary condition. Time-dependent heat and mass transport equations of each control volume for forced convection case have been simultaneously solved together. An implicit finite difference approach has been applied for the numerical solution of transport equations. Fortran programming language has been used to develop the numerical model. As a result; temperature and humidity ratio distribution, the amount of vapor transpiration from food products, and the amount of condensation on the underside of the upper surface due to heat-and-mass transport and transpiration characteristics of the products have been time-dependently calculated.

Keywords

Surface condensation; food respiration; transpiration; humidity; moisture loss; water vapor; mass concentration; finite difference

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