Application of response surface methodology to investigate the effect of different variables on conversion of palm kernel shell in steam gasification using coal bottom ash

Optimization of energy consumption and temperature fluctuations for a household freezer using non‐toxic and non‐flammable eutectic phase change materials with a cascade arrangement

“…A high F ‐value and low p ‐value indicate that the model is significant to predict the responses. Both the coefficient of determination ( R 2 ) and the adjusted coefficients of determination ( R 2 adj ) indicate goodness‐of‐fit for the model 21 …”

“…We used the Response Surface Methodology (RSM) to optimize the test conditions as it is a useful technique for analyzing and optimizing a response with respect to the independent variables 25 . The most popular RSM technique, and one that is able to be used to fit the second order polynomial equations, is Central Composite Design (CCD), a useful method to evaluate the curvature of the non‐linear response surface 21 . In present work, we used a three‐level, three‐factor central compost design consisting of 18 experiments to investigate the effect of phase change temperature and the amount of PCMs located inside the freezer on the reduction rates of energy consumption and of temperature fluctuations.…”

“…25 The most popular RSM technique, and one that is able to be used to fit the second order polynomial equations, is Central Composite Design (CCD), a useful method to evaluate the curvature of the non-linear response surface. 21 In present work, we used a three-level, three-factor central compost design consisting of 18 experiments to investigate the effect of phase change temperature and the amount of PCMs located inside the freezer on the reduction rates of energy consumption and of temperature fluctuations. Phase change temperature and the amount of latent heat storage elements used inside the freezing chamber are two factors that affect refrigeration systems' performance and the amount of energy they consume.…”

“…PEG is one of the most suitable PCM for this work due to its high latent heat storage capacity, low vapor pressure, good chemical and thermal stabilities, various molecular weights and phase change temperatures, non‐toxicity and reasonable price. In previous two published articles the application of PCM in the household refrigerators and freezers has been discussed 20,21 . This Considering the temperature distribution inside freezers, this work presents a novel household freezer using two eutectic PCMs with different melting points arranged in a cascade configuration inside the interior compartment in order to minimize temperature fluctuations in products stored in it and to reduce energy consumption.…”

“…A three‐level, three‐factor central compost design (CCD) has been employed in this work. This design is found to be a useful optimization technique due to the advantage of analyzing multifactor problems with a fewer number of experimental runs 21 . The effect of three independent factors on two responses of energy consumption and temperature fluctuation inside the freezer were analyzed.…”