Inemesit Edem Ekop^1,, Kayode Joshua Simonyan², Udochukwu Nelson Onwuka²

This study was conducted to investigate and compare the thermal properties of two varieties: Tympanotonus fuscatus and Pachymelania aurita of Periwinkle in Nigeria. The thermal properties, namely; specific heat capacity,C_p, thermal conductivity, k, thermal diffusity,α, thermal absorptivity, γ and thermal effusivity, ∈ of Periwinkle samples were determined. The mean thermal conductivity of T. fuscatus was found to be 0.085±0.00015 W/m.K at temperatures of 308 – 373 K, while that of P. aurita was 0.0952±0.00056 W/m.K at the same temperature range.The average specific heat capacity value of T. fuscatus was found to be 2403.663±3.4379 J/kg.K at temperature of 308 – 373 K lower than that of P. aurita having a mean value of 2832.314±1.7385 J/kg.K at the same temperature. The mean thermal diffisivity of T. fuscatus was found to be 2.6553×10^-8 m²/s while that of P. aurita was found to be 5.6790×10^-8 m²/s. The average values for thermal absorptivity and effusivity of T. fuscatus and P. aurita were obtained as 81.085m^-1; 525.084 W.s^1/2/m²K and 55.441 m^-1; 396.952 W.s^1/2/m²K, respectively. The results shown that average thermal absorptivity and effusivity values were higher in T. fuscatus than P. aurita. A Tukey pairwise comparison analysis carried out on the mean values of these thermal properties of T. fuscatus and P. aurita revealed that there is statistically significant difference at α<5% between the thermal properties of the two varieties of periwinkle samples. These data would help us in predicting and controlling the heat flux during the design of periwinkle processing equipment.

periwinkle varieties, T. fuscatus, P. aurita, specific heat capacity, thermal conductivity, thermal diffusivity, thermal properties