Modelling of the Thermophysical Properties of Ground Dika Kernel (Irvingia wombolu Vermoesen) as Affected by Temperature and Moisture Content

Abstract

The specific heat capacity and thermal conductivity of the ground dika (Irvingia wombolu Vermoesen) kernel were measured using the thermal probe method. Bulk density was determined using the graduated cylinder and the value obtained was used to calculate thermal diffusivity. The effects of temperature (Room temperature – 90  ) and moisture content (5.17 – 20% wet basis) on the thermo physical properties of the ground and hydrated dika kernel were studied. Linear, quadratic and cubic regressions were modelled at each temperature as a function of the corresponding moisture contents, and the best model was selected based on the coefficient of determination (R2) values. The results of the specific heat capacity ranged between 0.951 and 3.089 kJ/kg , thermal conductivity (4.36 and 31.87 W/m *105), bulk density (0.492 and 0.680 g/cm3) and the thermal diffusivity values between 6.313 and 43.065 m2/s*105. All the values are within literature range. The result of the investigation revealed that thermo physical properties were moisture content and temperature dependent, and quadratic equation fitted all the models than linear equation for all the properties investigated. The data obtained from the study can be used in the process design of the ground kernel or the soup on a commercial scale.