Purpose This paper aims to deal with the study of heat and mass transfer on double-diffusive three-dimensional hydromagnetic boundary layer flow of an electrically conducting Casson nanofluid over a stretching surface. The combined effects of nonlinear thermal radiation, magnetic field, buoyancy forces, thermophoresis and Brownian motion are taken into consideration with convective boundary conditions. Design/methodology/approach Similarity transformations are used to reduce the governing partial differential equations into a set of nonlinear ordinary differential equations. The reduced equations were numerically solved using Runge–Kutta–Fehlberg fourth-fifth-order method along with shooting technique. Findings The impact of several existing physical parameters such as Casson parameter, mixed convection parameter, regular buoyancy ratio parameter, radiation parameter, Brownian motion parameter, thermophoresis parameter, temperature ratio parameter on velocity, temperature, solutal and nanofluid concentration profiles are analyzed through graphs and tables in detail. It is found that the solutal component increases for Dufour Lewis number, whereas it decreases for nanofluid Lewis number. Moreover, velocity profiles decrease for Casson parameter, while the Nusselt number increases for Biot number, radiation and temperature ratio parameter. Originality/value This paper is a new work related to three-dimensional double-diffusive flow of Casson nanofluid with buoyancy and nonlinear thermal radiation effect.

Purpose The features of coated wire product are measured by the flow and heat transport occurring in the interior of dies. Therefore, an understanding of characteristics of polymers momentum, heat mass transfer and wall shear stress is of great interest. Enhancement of heat transfer rate is fundamental need of wire coating process. Therefore, this study aims to investigate the effect of suspended nanoparticles in heat and mass transport phenomena of third-grade liquid in post-treatment of wire coating process. Buongiorno model for nanofluid is adopted. Two cases of temperature dependent viscosity are considered. Design/methodology/approach The governing equations are modelled with the help of steady-state conservation equations of mass, momentum, energy and nanoparticle concentration. Some appropriate dimensionless variables are introduced. Numerical solutions for the nonlinear problem are developed through Runge–Kutta–Fehlberg technique. The outcome of sundry variables for dimensionless flow, thermal and nanoparticle volume fraction fields are scrutinised through graphical illustrations. Findings The study’s numerical results disclose that the force on the total wire surface and shear stress at the surface in case of Reynolds Model dominate Vogel’s Model case. Impact of nanoparticles is constructive for force on the total wire surface and shear stress at the surface. The velocity of the coating material can be enhanced by the non-Newtonian property. Practical implications This study may provide useful information to improve the wire coating technology. Originality/value Effect of nanoparticles in wire coating analysis by using Brownian motion and thermophoresis slip mechanisms is investigated for the first time. Two different models for variable viscosity are used.

The present attempt is made to elaborate the features of triple diffusive convective flow of an incompressible nanoliquid induced by horizontal surface under buoyancy forces. The effect of nonlinear thermal radiation is taken into account. Heat flux model of radiation is formulated through Rosseland's approximation. The radiation phenomenon plays a key role in modern solar energy equipment's. The nondimensional variables are introduced to convert the dimensional mathematical expressions into dimensionless single independent variable. Numerical scheme is developed to obtain the solution of mathematical model. The importance of controlling constraints on flow quantities are characterized through plots. The quantities of engineering importance are computed and elaborated graphically. It is noticed that the presence of salts and nanoparticles enhance the thermal performance of base liquid. The liquid temperature and its relevant thickness of thermal layer improved significantly with an increment in the values of radiative parameter. The larger values of parameters of Brownian motion and thermophoretic correspond to higher temperature profiles.

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The heat and mass transfer of rotating Casson nanofluid flow is incorporated in the present study. Influence of magnetic field, nonlinear thermal radiation, viscous dissipation and Joule heating effects are taken into the account. A set of nonlinear ordinary differential equations are obtained from the governing partial differential equations with the aid of suitable similarity transformations. The resultant equations are solved for the numerical solution using Runge-Kutta-Fehlberg fourth-fifth order method along with shooting technique. The impact of several existing physical parameter on velocity, temperature and nanofluid concentration profiles are analyzed through graphs and tables in detail. It is found that, velocity component decreases and temperature component increases for rotating parameter.