Mechanical properties and melting conditions of beeswax for comb foundation forming

The melting conditions and the mechanical properties of beeswax after melting process were investigated in thisstudy. The study variables of melting process were hot water temperature, propeller speed and time. The empirical model ofbeeswax melting efficiency was then established. The melting conditions were optimized based on the melting efficiencyand color of beeswax and were found at the hot water temperature in range of 98°C -100°C, propeller speed in range of 40-90r/min and time in range of 12-15 min. The beeswax was solidified at the different cooling rates. The compression testswere performed at condition of 60% strain to characterize the mechanical behavior of beeswax. The constitutive equationfor hyperelastic material was employed for beeswax. The two forms of the constitutive equation showed a better fit to theexperimental data and the optimized material parameters were obtained. The rolling beeswax sheets were simulated underthe different conditions of pressure angle, velocity and friction coefficient in order to determine the effect of the variables onthe mechanical properties of beeswax sheet. The stress and deformation distributions across the beeswax sheet including theforces acting on the contact interfaces were examined. The pressure angle was found to be the most effective variable on thestress distribution. The maximum pressure angle of 11° was found to provide the non-defect beeswax sheet. This presentmodel for beeswax sheet rolling provides the understanding of the stress and deformation distributions and has been utilizedto design the rolling for comb foundation forming

Empirical Modeling on Hot Air Drying of Fresh and Pre-treated Pineapples

This research was aimed to study drying kinetics and determine empirical model of fresh pineapple and pre-treated pineapple with sucrose solution at different concentrations during drying. 3 mm thick samples were immersed into 30, 40 and 50 Brix of sucrose solution before hot air drying at temperatures of 60, 70 and 80°C. The empirical models to predict the drying kinetics were investigated. The results showed that the moisture content decreased when increasing the drying temperatures and times. Increase in sucrose concentration led to longer drying time. According to the statistical values of the highest coefficients (R2), the lowest least of chi-square (χ2) and root mean square error (RMSE), Logarithmic model was the best models for describing the drying behavior of soaked samples into 30, 40 and 50 Brix of sucrose solution