Using a quasi-static approach valid for Stefan numbers less than one, we derive approximate equations governing the movement of a phase change front for materials which generate internal heat. These models are applied for both constant surface temperature and constant surface heat flux boundary conditions, in cylindrical, spherical, plane wall and semi-infinite geometries. Exact solutions with ...

In the present study, Computational Fluid Dynamics (CFD) techniques and Artificial Neural Networks (ANN) are used to predict the pressure drop value (Δp ) of Al2O3-water nanofluid in flat tubes. Δp  is predicted taking into account five input variables: tube flattening (H), inlet volumetric flow rate (Qi  ), wall heat flux (qnw  ), nanoparticle volume fraction (Φ) and nanoparticle diameter (dp ...

h = heat transfer coefficient q = heat flux from the wall of evaporator to refrigerant Tw =Temperature at the wall of evaporator Tf = Temperature of the refrigerant kal = Conductivity of aluminum t = Thickness of evaporator M& = Mass flow rate of refrigerant Cp = Constant-pressure specific heat of refrigerant Tsat = Saturation temperature of refrigerant Tin = Temperature of refrigerant at inlet...

Cp = heat capacity at constant pressure, J= K kg Cv = heat capacity at constant volume, J= K kg c = concentration, mol=m E = total energy, J=m H = shape factor, = , dimensionless h = specific enthalpy, J=kg h = heat of formation, J=kg J = diffusive mass flux, kg=m s Keq = equilibrium constant k = reaction rate coefficient Le = Lewis number, dimensionless M = Mach number, dimensionless ns = tota...

In this paper the two-dimensional flow of a micropolar fluid through porous medium over a continuously moving porous vertical plate under the combined buoyancy effects of thermal and heat source has been studied under the action of transverse magnetic field taking into account the thermal radiation field. The Roseland approximation is used to describe radiative heat transfer in the limit of opt...

Calcined coke is an important material for making carbon anodes for smelting of alumina to aluminum. Calcining is an energy intensive industry and a significant amount of heat is wasted in the calcining process. Efficiently managing this energy resource is tied to the profit margin and survivability of a calcining plant. To help improve the energy efficiency of the calcining process, a 3-D comp...

    Given the need to increase the efficiency of heat transfer in thermal systems, especially systems using nanofluids in microscale and nanoscale heat transfer equipment ideas to improve their performance is very good.In present study, the flow and heat transfer of Water-Cu nanofluid in micro-tube with slip regime with constant wall heat flux numerically simulated with low Reynolds numbers. Sl...