Numerical Simulation of Heat Transfer in a Square Cavity with a Heater and Cooler Using Hybrid Nanofluid and Random Temperature

is study uses numerical simulations to investigate the characteristics of laminar natural convection in a square cavity filled with a mixed nanofluid containing Ag and Ag-TiO2 solid spherical nanoparticles. The cavity contains one heat source and one heat sink, and the cavity walls are adiabatic. The fluid is a water-based hybrid nanofluid. The temperature in the cavity is randomized using a random function. The main parameters, including volume fraction of nanoparticles, temperature type, and type of hybrid nanofluid, are varied and analyzed using the finite volume method. The numerical results are compared with previous studies, and good agreement is observed. The obtained results show that the addition of nanoparticles significantly enhanced the heat transfer in the cavity (φ=0.1%). In addition, the larger Rayleigh number, the more obvious the influence of temperature type. Also, the average Nusselt number increases as the volume fraction increases, and the best results are obtained from the (Ag-TiO2)/water hybrid nanofluid.