Perilaku Perpindahan Panas dalam Proses Penyangraian dengan Media Pasir = Behavior of Heat Transfer in Roasting Process with Sand Media

The research aimed to study the lump heat capacity analysis. It was observed the solution of coefficient analysis of surface heat transfer (h) with influenced factors in roasting process by sand media used rotary roster. The experiment used ball like model made from clay as roasted material and brass ball as a comparison under a relative constant temperature at 120 °C. Function relationship of (nj = C.( n^X n^ was established using dimension analysis. The constant C, p and a were obtained through multiple linear regression analysis. The parameter h was required through dependent variables. Based on a analysis with two independent variables dm and N could be obtained empirical function of surface heat transfer coefficient h (W/m2°C) as follows: with km= sand thermal conductivity (W/m°C)pm= media density (kg/m3)Cpm = media specific heat (J/kg°C)dm = media diameter (m)N = rotating of roasting (rpm)db=diameter of roasted materials (m) and a, b and C = constants. The applicability of established temperature function for h in predicting temperature of roasting material during roasted had been successfully provide. Keywords: roasting -oeffkient of heat transfer and Dimension analysis