Investigating Thermal Stability in a Two-Step Convective Radiating Cylindrical Pipe

Thermal stability in a stockpile of reactive materials is analyzed in this article. The combustion process is modelled in a long cylindrical pipe that is assumed to lose heat to the surrounding environment by convection and radiation. The study of effects of different kinetic parameters embedded on the governing differential equation, makes it easier to investigate the complicated combustion process. The combustion process results with nonlinear molecular interactions and as a result it is not easy to solve the differential equation exactly, and therefore the numerical approach by using the Finite Difference Method (FDM) is applied. The numerical solutions are depicted graphically for each parameter’s effect on the temperature of the system. In general, the results indicate that kinetic parameters like the reaction rate promote the exothermic chemical reaction process by increasing the temperature profiles, whilst kinetic parameters such as the order of the reaction show the tendency to retard the combustion process by lowering the temperature of the system.

Modeling and Simulations of Buongiorno’s Model for Nanofluid in a Microchannel with Electro-Osmotic Effects and an Exothermal Chemical Reaction

The article presents a mathematical model for the magnetized nanofluid flow and heat transfer with an exothermic chemical reaction controlled by Arrhenius kinetics. Buongiorno’s model with passive boundary condition is employed to formulate the governing equation for nanoparticles concentration. The momentum equation with slip boundary conditions is modelled with the inclusion of electroosmotic effects which remain inattentive in the study of microchannel flows with electric double layer (EDL) effects. Conclusions are based on graphical and numerical results for the dimensionless numbers representing the features of heat transfer and fluid flow. Frank-Kamenetskii parameter resulting from the chemical reaction showed significant effects on the optimization of heat transfer, leading to increased heat exchangers’ effectiveness. The Hartmann number and slip parameter significantly affect skin friction, demonstrating the notable effects of electroosmotic flow and the exothermic chemical reaction on heat transfer in microchannels. This analysis contributes to prognosticating the convective heat transfer of nanofluids on a micro-scale for accomplishing successful thermal designs.

Impact of Newtonian heating and Fourier and Fick’s laws on a magnetohydrodynamic dusty Casson nanofluid flow with variable heat source/sink over a stretching cylinder

The present investigation aims to deliberate the magnetohydrodynamic (MHD) dusty Casson nanofluid with variable heat source/sink and modified Fourier’s and Fick’s laws over a stretching cylinder. The novelty of the flow model is enhanced with additional effects of the Newtonian heating, activation energy, and an exothermic chemical reaction. In an exothermic chemical reaction, the energy of the reactants is higher than the end products. The solution to the formulated problem is attained numerically by employing the MATLAB software function bvp4c. The behavior of flow parameters versus involved profiles is discussed graphically at length. For large values of momentum dust particles, the velocity field for the fluid flow declines, whereas an opposite trend is perceived for the dust phase. An escalation is noticed for the Newtonian heating in the temperature profile for both the fluid and dust-particle phase. A comparison is also added with an already published work to check the validity of the envisioned problem.

Transient Heat Analysis in a Two-Step Radiative Combustible Slab

In this article, analysis of heat transfer in a stockpile of reactive materials modelled in a rectangular slab is carried out. A two-step exothermic chemical reaction is assumed and the heat loss to the surrounding environment is by radiation. The ordinary differential equation (ODE) governing the problem is tackled numerically by Runge-Kutta Fehlberg (RKF45) method coupled with Shooting technique. The heat transfer analysis is simplified by investigation some kinetic parameters’ effects on the temperature of the combusting system. It was found out that some kinetic parameters raise the levels of the temperature by encouraging the exothermic chemical reaction, whereas some, reduce the levels of the temperature to slow down the heat transfer rate. The results are depicted graphically and discussed accordingly.