STUDY OF FROST GROWTH AROUND A CYLINDER WITH VARYING ENVIRONMENT PARAMETER

Abstract

This describes a one-dimensional model which permits the evaluation of the local properties during frost growth. To achieve this objective it is necessary to know the local coefficients of .heat transfer which are determined by solving mass and energy equations. A numerical solution is obtained for Reynold number upto 200 and buoyancy parameter upto 35. Whenever moist air comes in contact, with a surface whose temperature is below the dew point temperature of water vapour in air, moisture will condense on the surface. temperature is also below freezing, frost will form. Due to formation of frost overall heat transfer is reduces. A simple method of computing heat transfer and frost growth rates as well as the frost thickness and surface temperature as the function of time and position. The method utilizes knownconvective heat transfer correlations for horizontal -cylinder and the Lewis analogy to determine a convective mass transfer coefficient and enthalpy transfer coefficient. An iterative quasi-steady-state approach adopted to compute the air-frost interface temperature, frost properties, the partial pressure of water vapour at the frost surface and the frost thickness