Melting Characteristics of a Phase Change Material Mixed with Nano Particles of Cobalt Oxide Bounded in a Trapezoidal Structure

A novel trapezoidal design for storage of heat energy through melting of phase-change material(PCM)is investigated.Latent heat thermal energy storage system(LHTES)is a promising option to diminish mis-match between energy consumption and supply.For this purpose,Paraffin:Rubitherm-35(RT35)material is successively melted in aluminum structure which is heated from one side and the other sides are kept adiabatic.Melting of PCM is observed experimentally and melt fronts are photographed for various time lengths.The fluid-solid module in COMSOL Multiphysics 5.4 has been utilized.The transient heat conduction with enthalpy function is hired.Simulations are carried out for enhancement of thermal conductivity through addition of nano-entities of cobalt oxide Co3O4.Themelting time is notably reduced with inclusion of nano-entities to enhance thermal conductivity.The time spans for melt start and total melt in case of pure PCM are 375 and 4500(s)respectively whereas for the nano mix case,these are 150 and 3000 s.Thus 33%shorter time length is noticed for charging of the PCM trapezoidal matrix with nano entities of Co3O4 aremixed.The results fromsimulation and lab observations depict similar patterns and are in quite close comparison.

Analysis of series RL and RC circuits with time-invariant source using truncated M,Atangana beta and conformable derivatives

Complex processes of the physical world require novel and sophisticated mathematical notions to get deep insights.In this research analysis,two standard mathematical models for the series RL and RC circuits having time-invariant sources taken from the discipline of electrical engineering have been investigated with the help of differential operators known with the name of truncated M-derivative,Atangana beta-derivative,and the conformable derivative operators.The exact solutions for these two models have been found in terms of the transcendental exponential function of time under the truncated M-derivative,Atangana beta-derivative,and the conformable derivative operators.The numerical simulations carried out via MATLAB”9.4.0.813654(R2018a)”have been interpreted to explore new behavior for solutions of the models not possible to obtain through standard classical calculus wherein one is restricted to have integer-order derivatives unlike the differential operators used in the present research study.The models under consideration for the three differential operators have been investigated with varying parameters’values including the differential ordersαandβwhereupon the classical case is resumed forα=β=1 andτ=0.