The effects of Joule-heating, chemical reaction and thermal radiation on unsteady MHD natural convection from a heated vertical porous plate in a micropolar fluid are analyzed. The partial differential equations governing the flow and heat and mass transfer have been solved numerically using an implicit finite-difference scheme. The case corresponding to vanishing of the anti-symmetric part of the stress tensor that represents weak concentrations is considered. The numerical results are validated by favorable comparisons with previously published results. A parametric study of the governing parameters, namely the magnetic field parameter, suction/injection parameter, radiation parameter, chemical reaction parameter, vortex viscosity parameter and the Eckert number on the linear velocity, angular velocity, temperature and the concentration profiles as well as the skin friction coefficient, wall couple stress coefficient, Nusselt number and the Sherwood number is conducted. A selected set of numerical results is presented graphically and discussed.

Unsteady MHD natural convection from a heated vertical porous plate in a micropolar fluid with Joule heating, chemical reaction and radiation effects

Influence of radiation on unsteady hydromagnetic natural convection transient flow near an impulsively moving vertical flat plate with ramped wall temperature in a porous medium is studied. Exact solution of momentum and energy equations, under Boussinesq approximation, is obtained in closed form by Laplace transform technique. The variations in fluid velocity and temperature are shown graphically whereas numerical values of skin friction and Nusselt number are presented in tabular form.

MHD natural convection flow with radiative heat transfer past an impulsively moving plate with ramped wall temperature

Effect of viscous dissipation and radiation on natural convection in a porous medium embedded within vertical annulus

An analysis is performed to study the momentum, heat and mass transfer characteristics of MHD natural convection flow over a permeable, inclined surface with variable wall temperature and concentration, taking into consideration the effects of ohmic heating and viscous dissipation. Power-law temperature and concentration variations are assumed at the inclined surface. The resulting governing equations are transformed using suitable transformations and then solved numerically by an implicit finite-difference method. The solution is found to be dependent on several governing parameters, including the magnetic field strength parameter, Eckert number, the buoyancy ratio between species and thermal diffusion, Prandtl number, Schmidt number, wall temperature and concentration exponent, the inclination angle from the vertical direction, and the injection parameter. A parametric study of all the governing parameters is carried out and representative results are illustrated to reveal a typical tendency of the solutions. Representative results are presented for the velocity, temperature, and concentration distributions as well as the local friction coefficient, local Nusselt number, and the local Sherwood number.

Heat and mass transfer in MHD flow by natural convection from a permeable, inclined surface with variable wall temperature and concentration

Heat transfer in porous cavity under the influence of radiation and viscous dissipation

Influence of viscous dissipation and radiation on unsteady MHD free-convection flow past an infinite heated vertical plate in a porous medium with time-dependent suction

The paper focused on the economic effects of hazardous waste due to oil and gas companies in Rivers State. It include direct, indirect, and induced impacts on jobs, labour income and value addition. Hazardous waste, could be a source of job creation and revenue generation, if properly managed. However, poor management of hazardous waste can cause great danger to environment, plants animals and human life. There are five major waste disposal dumpsites in Port Harcourt metropolis. The present study was restricted to three functioning dump sites at Rumuorlumeni, Igwuruta, and Eliozu. Data were collected from a wide range of subjects to elicit acceptable generalization, and then analyzed and tested in the laboratory. The results showed the p values of the dumpsite dot and parameters measured are significant at 5%, while the p-value of the locations considered is significant at 10%. Hence, there is a significant difference among dumpsite dot parameters measured and the three locations considered. The least squared difference comparison tests were done to identify the significant factors. It showed that the regions where hazardous wastes are dumped are barren due to the presence of heavy metal as they render the soil unfertile to permit crops and plants to germinate and affect on agriculture.

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Effects of hazardous waste discharge from the activities of oil and gas companies in Nigeria

The paper examines transient MHD Couette flow of an electrically conducting fluid in the presence of an applied transverse magnetic field and thermal radiation through a porous medium. The dimensionless governing equations of the flow are coupled non-linear partial differential equations and are solved by an efficient and unconditionally stable finite difference scheme of Crank–Nicolson type. The influence of the medium permeability is also assessed. The velocity and temperature profiles for the flow are studied for various interesting parameters of Prandtl number, Nahme number and Hartmann number, and are presented graphically. The results show that the thermal radiation has appreciable influence on the flow.

https://jafmonline.net/JournalArchive/download?file_ID=15331&issue_ID=207

Influence of Thermal Radiation on a Transient MHD Couette Flow through a Porous Medium

Very low frequency electromagnetic (VLF-EM) response from a lead sulphide lode in the Abakaliki lead/zinc field, Nigeria

This paper investigates the condition leading to the onset of stationary convection in a low Prandtl number horizontal fluid layer in a porous medium heated from below with internal heat source. The internal heat source is taken as directly proportional to the temperature leading to a sinusoidal temperature gradient in the fluid layer. The effects of heat generation, porosity parameter and different Prandtl numbers, Pr are presented. The results show that the onset of stationary instability is hastened by increasing values of the internal heat generation as well as increments in the Prandtl number. Further, increases in the porosity parameter delayed the onset of stationary instability.

C Israel-Cookey

Papers

Influence of viscous dissipation and radiation on unsteady MHD free-convection flow past an infinite heated vertical plate in a porous medium with time-dependent suction

Effects of hazardous waste discharge from the activities of oil and gas companies in Nigeria

Influence of Thermal Radiation on a Transient MHD Couette Flow through a Porous Medium

Very low frequency electromagnetic (VLF-EM) response from a lead sulphide lode in the Abakaliki lead/zinc field, Nigeria

Onset of thermal instability in a low Prandtl number fluid with internal heat source in a porous medium