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In this study, the Tiwari and Das model is numerically studied, in case of a moving plate containing both single-walled and multiwalled carbon nanotubes (SWCNTs and MWCNTs, respectively), in the presence of thermal radiation and the slip effect. Employing the similarity transformation, a set of 2nd-order partial differential equations (which are used to model the flow and heat transfer) are solved numerically using the boundary value problem with 4th-order accuracy (BVP4C) method. The effects of related parameters, such as the volume fraction of nanoparticles, moving, slip, and radiation parameter on the heat transfer performance are analysed and discussed. Results indicate that a unique solution was placed when the plate travels in assisting flow conditions. Additionally, as the nanoparticle volume fraction (φ) rises at φ = 0.2, the skin friction and heat transfer rate decrease. It is also observed that when the slip parameter (β) increases at β = 0.4, the skin friction decreases, whereas the heat transfer rate increases. Meanwhile, the heat transfer rate decreases when the thermal radiation (NR) increases to 0.7. Moreover, it is found that the SWCNTs are more efficient when the skin friction coefficient and the Nusselt number are considered. It is found that the Weibull distribution is more suitable in fitting the skin friction data. [ABSTRACT FROM AUTHOR]

The heat and mass transfer of carbon nanotubes based-water nanofluids flowing through a moving plate was thoroughly investigated in this numerical work. The Tiwari and Das nanofluid model, as well as the Buongiorno nanofluid model, are formulated to characterise the problem. In transforming the governing partial differential equations into a dimensionless ordinary differential equation, similarity transformations are introduced. The numerical solver bvp4c was then deployed to investigate the dimensionless differential equations. The impact of main parameters on the skin friction, Nusselt and Sherwood numbers are elucidated and thoroughly explained. Results are then compared with published works, and the outcomes are genuinely in close alliance. With the occurrence of thermophoresis Nt , Brownian motion Nb and nanoparticle volume fraction φ , the heat and mass transfer performance are outlined. The local number Nusselt seems to be decreased by higher parameters φ , Nb and Nt. Besides, the local Sherwood number is augmenting with an increase in the φ and Nb parameters and, inversely, a decreasing function with a lower Nt parameter. The results obtained from this study may lead to new knowledge and indirectly contribute to the fluid engineering industry. [ABSTRACT FROM AUTHOR]

This study is to investigate the magnetohydrodynamic (MHD) stagnation point flow and heat transfer characteristic nanofluid of carbon nanotube (CNTs) over the shrinking surface with heat sink effects. Similarity equations deduced from momentum and energy equation of partial differential equations are solved numerically. This study looks at the different parameters of the flow and heat transfer using first phase model which is Tiwari-Das. The parameter discussed were volume fraction nanoparticle, magnetic parameter, heat sink/source parameters, and a different type of nanofluid and based fluids. Present results revealed that the rate of nanofluid (SWCNT/kerosene) in terms of flow and heat transfer is better than (MWCNT/kerosene) and (CNT/water) and regular fluid (water). Graphically, the variation results of dual solution exist for shrinking parameter in range λ c < λ ≤ − 1 for different values of volume fraction nanoparticle, magnetic, heat sink parameters, and a different type of nanofluid. However, a unique solution exists at − 1 < λ < 1 , and no solutions exist at λ < λ c which is a critical value. In addition, the local Nusselt number decreases with increasing volume fraction nanoparticle when there exists a heat sink effect. The values of the skin friction coefficient and local Nusselt number increase for both solutions with the increase in magnetic parameter. In this study, the investigation on the flow and heat transfer of MHD stagnation point nanofluid through a shrinking surface with heat sink effect shows how important the application to industrial applications. [ABSTRACT FROM AUTHOR]