Nanofluid Flow And Heat Transfer Analytical Research In The Preparation Of Thin Film By Tape Casting

The research on the flow and heat transfer of nanofluid thin film can provide theoretical guidance for the optimization of material processing technology and the improvement of product performance.In this paper,the flow and heat transfer of three different type of fluids,Newtonian fluid,viscoelastic fluid and power-law fluid over a stretching sheet are studied respectively.The main researches in the paper are as follows:1)The paper studies the boundary layer flow and heat transfer of the Newtonian nanofluid due to a stretching sheet,the marangoni effect caused by the surface tension gradient of Newtonian fluid thin film is discussed.Governing PDEs are reduced into coupled non-linear ODEs by similarity transformation and then solved analytically and numerically by the homotopy analysis method(HAM)and shooting technique.The distribution features of boundary layer velocity and temperature are analyzed,and the effects of various physical parameters on the boundary layer velocity,temperature and film thickness are obtained.2)The boundary layer flow and heat transfer governing model of Oldroyd-B fluid over a stretching surface have been established,the influences of nanoparticles on the thermal conductivity of the base fluid are discussed.Two different types of nanoparticles Cu ang Ag are considered with poly vinyl alcohol(PVA)-water used as a base fluid.The coupled 4-order nonlinear ordinary differential equations are established by similarity transformation,the analytical solutions are obtained using the homotopy analysis method(HAM).The effects of various relevant parameters such as unsteady parameter,Prandtl number and volume fraction of nanoparticles on the flow field are elucidated.3)The flow and heat transfer of the power-law nanofluid thin film due to a stretching sheet with power law wall temperature have been investigated analytically.Based on analogy method of viscous diffusion of velocity field and thermal diffusion of temperature field in non-Newtonian fluid,Fourier's law is modified.The effects of magnetic field,the power-law velocity slip and power law wall temperature on the flow and heat transfer are analyzed.Three different types of nanoparticles Al2O3,TiO2 and CuO are considered with ethylene vinyl acetate copolymer(EVA)used as a base fluid.The governing equations are solved by using DTM-NIM which is combined the differential transform method(DTM)with Newton Iteration method(NIM),the influences of various parameters on the velocity and temperature fields are obtained.In this paper,the theoretical analysis and the analytical method,which lay the foundation for the research on the flow and heat transfer of nanofluids thin film.Meanwhile,our solution have excellent agreement with the previous results,the validity of the analytical methods used in the paper are illustrated.This can provide a new way to solve the nonlinear differential equations in other engineering fields.