Rayleigh-Bénard convection in liquids with nanoparticles is modelled as a single phase system with liquid properties like density, viscosity, thermal expansion coefficient, heat capacity and thermal conductivity modified by the presence of the nanoparticles. Expressions for the thermophysical properties are chosen from earlier works. The tri-modal Lorenz model is derived under the assumptions of Boussinesq approximation and small-scale convective motions. Ginzburg-Landau equation is arrived at from the generalized Lorenz model. The amplitudes of convective modes required for estimating the heat transport are determined analytically. A table is prepared documenting the actual values of the thermophysical properties of water, ethylene-glycol, engine-oil and glycerine with different nanoparticles, namely copper, copper oxide, titania, silver and alumina, and Nusselt number is calculated. Enhanced thermal conductivity being the reason for the enhancement of heat transport due to the presence of the nanoparticles is shown. Detailed discussion is made on the percentage increase of heat transport in twenty Newtonian nanoliquids compared to that in Newtonian liquids without nanoparticles.

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Forced flow of an electrically conducting Newtonian fluid due to an exponentially stretching sheet is studied numerically. Free stream velocity is present and so is suction at the sheet. The governing coupled, nonlinear, partial differential equations of flow and heat transfer are converted into coupled, nonlinear, ordinary differential equations by similarity transformation and are solved numerically using shooting method, and curve fitting on the data is done by differential transform method together with Padé approximation. Prescribed exponential order surface temperature (PEST) and prescribed exponential order surface heat flux are considered for investigation of heat transfer related quantities. The influence of Chandrasekhar number, suction/injection parameter, and freestream parameter on heat transport is presented and discussed. Coefficient of friction and heat transport is also evaluated in the study. The results are of interest in extrusions and such other processes.

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