Effects of chemical reaction, viscosity, thermal conductivity, heat source, radiation/absorption, on MHD mixed convection nano-fluids flow over an unsteady stretching sheet by HAM and numerical method

Investigations are performed for further observations of heat and mass transfer in magneto-hydrodynamic mixed-convectional nano-fluid flow with the assumption of variable viscosity and thermal-conductivity over an unsteady stretching sheet. Base fluid is Carboxy-methyl cellulose (CMC) water as a carrier fluid with different nano-particles such as [Formula: see text] (Titanium), Ag (Silver), [Formula: see text] (Aluminum), and Cu (Copper). Flow contains different physical parameters, such as heat source, chemical reaction effect, Schmidt number, and radiation absorptions effects are observed to be significant in the presences of magnetic field. Obtained equations are solved by numerically BVP4C-package (shooting method) and analytically by BVPh2.0-package (Homotopy Analysis Method “HAM”). Interested physical quantities are, viscosity-parameter ( A), Thermal-conductivity parameter ( N),Thermocapillary-number ( M), Hartmann-number (Ma), Prandtl-number (Pr), 4-nano-particles ([Formula: see text]), temperature Grashof number ([Formula: see text]), and mass Grashof number ([Formula: see text]) are the focus to the velocity, temperature, and solute concentration profiles. It is concluded that, Solute concentration of ([Formula: see text])-water has higher than the other 3-nano-fluids. Mass flux, heat flux, and Skin friction of fluids are direct functions of magnetic force, while inverse function of temperature. Magnetic force also decreased the speed of fluids and hence mass flux reduced which implies that, the temperature reduces. [Formula: see text] has also inverse relation with mass flux, heat flux, and skin friction, while direct relation with the speed of fluids. Similarly, [Formula: see text] has inverse relation with [Formula: see text], [Formula: see text], and [Formula: see text], but direct relation with [Formula: see text]. Different results are shown in graphical and tabular form.

Improving the Thermal Efficiency of Flat Plate Solar Collector Using Nano-Fluids as a Working Fluids: A Review

Solar energy is one of the most important types of renewable energy and is characterized by its availability, especially in Iraq. It can be used in many applications, including supply thermal energy by solar collectors. Improving the thermal efficiency of solar collector leads to an increase in the thermal energy supplied. Using a nano-fluid instead of base fluid (water is often used) as a working fluid is a method many used to increase the thermal efficiency of solar collectors. In this article, the latest research that used nano-fluid as a working fluid in evaluating the thermal efficiency of solar collector, type flat plate was reviewed. The thermal efficiency improvement of flat plate solar collector was reviewed based on the type of nanoparticles (metal oxides, semiconductors oxides, carbon compounds) used in the base fluid and comparison was made between these nanoparticles under the same conditions. Moreover, the effect of varying the concentration of nanoparticles in the base fluid and changing the working fluid flow rate on the thermal efficiency of flat plate solar collector was also reviewed. The results of the review showed that nano-fluids containing carbon compounds are better than other nano-fluids and that copper oxide is better than the rest of the metal oxides used in improving the thermal efficiency of flat plate solar collectors.

Review on Magnetohydrodynamic flow of nanofluids past a Vertical plate under the influence of Thermal Radiation

Nanofluids are the fluids containing nano materials, with interesting properties, and the distinctive features have shown unprecedented potential for many Industrial applications. Nano fluids have been receiving great attention in recent years for heat transfer applications in industrial processes. In literature, the highly nonlinear governing equations involved in the study of MHD nanofluids flow with thermal radiation past a vertical plate under varying physical nature are solved using numerical and analytical schemes. It is noted that due to the complexity of the governing equations, numerical schemes are more preferable than analytical schemes. The authors have taken effort in registering various forms of governing equations involved in the above studies, its impact on velocity and temperature field. This paper also tries to identify the research gaps and pave way for future research.