Heat transfer augmentation through engine oil-based hybrid nanofluid inside a trapezoid cavity

Abstract

Heat transfer occurs as a result of density differences caused by temperature changes. It has several industrial applications. To improve performance, one must investigate the heat transfer behaviour of the working fluid. Hence, the purpose of this work is to report a heat transfer analysis of a partially heated trapezoid cavity filled with a hybrid nanofluid. The temperature conditions of the cavity are such that the bottom boundary is partially heated, inclined side boundaries are kept at a lower temperature, and the upper boundary is kept adiabatic. A trapezoidal shape heated obstacle is considered in the cavity’s centre. The heat transfer and flow take place inside the cavity due to density variation. The mechanism is regulated by mass, momentum, and energy conservation, as well as related boundary constraints. The solutions are determined by the use of a numerical technique known as the Finite Element Method after the governing equations are transformed into non-dimensional form, which brings up physical parameters affecting the heat transfer and flow. The initial study is performed for three types of nanofluids with silver 𝐴𝑔 and magnesium oxide 𝑀𝑔𝑜 nanoparticles inside water 𝐻2𝑂, kerosene 𝐾𝑒, and engine oil 𝐸𝑂. The study revealed that the engine oil-based hybrid nanofluid produced an increased heat transfer rate. Simulation is performed using engine-based hybrid nanofluid with the range of physical parameters, such as Rayleigh number 𝑅𝑎 (105≤𝑅𝑎≤107), Hartmann number 𝐻𝑎 (0≤𝐻𝑎≤100) and nanoparticles volume fraction 𝜙 (0≤𝜙≤0.2). It is found that the heat transfer rate is enhanced by increasing the fraction of nanoparticles in the base fluid. Moreover, imposition of magnetic field has reverse impact on the fluid movement.