Enhancement of an Air-Cooled Battery Thermal Management System Using Liquid Cooling with CuO and Al2O3 Nanofluids under Steady-State and Transient Conditions

Lithium-ion batteries are a crucial part of transportation electrification. Various battery thermal management systems (BTMS) are employed in electric vehicles for safe and optimum battery operation. With the advancement in power demand and battery technology, there is an increasing interest in enhancing BTMS’ performance. Liquid cooling is gaining a lot of attention recently due to its higher heat capacity compared to air. In this study, an air-cooled BTMS is replaced by a liquid cooled with nanoparticles, and the impacts of different nanoparticles and flow chrematistics are modeled. Furthermore, a unique approach that involves transient analysis is employed. The effects of nanofluid in enhancing the thermal performance of lithium-ion batteries are assessed for two types of nanoparticles (CuO and Al2O3) at four different volume concentrations (0.5%, 2%, 3%, and 5%) and three fluid velocities (0.05, 0.075, and 0.1 m/s). To simulate fluid flow behavior and analyze the temperature distribution within the battery pack, a conventional k-ε turbulence model is used. The results indicate that the cooling efficiency of the system can be enhanced by introducing a 5% volume concentration of nanofluids at a lower fluid velocity as compared to pure liquid. Al2O3 and CuO reduce the temperature by 7.89% and 4.73% for the 5% volume concentration, respectively. From transient analysis, it is also found that for 600 s of operation at the highest power, the cell temperature is within the safe range for the selected vehicle with nanofluid cooling. The findings from this study are expected to contribute to improving BTMS by quantifying the benefits of using nanofluids for battery cooling under both steady-state and transient conditions

Numerical investigation on turbulent flow, heat transfer, and entropy generation of water-based magnetic nanofluid flow in a tube with hemisphere porous under a uniform magnetic field

This paper numerically investigates the forced convection and entropy generation of Fe3O4 water nanofluid inside a cylindrical tube with porous hemisphere media. The flow regime is turbulent under a uniform magnetic field and constant heat flux, and to solve the equations, the finite volume method is applied. The combination of nanofluid, magnetic field and porous hemisphere media on the flow and heat transfer in a tube is the main novelty. The effects of different parameters such as Reynolds number (10,000 to 25,000), porosity (ε = 20%, 40%, and 80%.), the solid volume fraction of nanofluid (0.5 vol%, 1 vol%, and 2.5 vol%), friction factor and entropy generation of Ferro-nanofluid in the tube are investigated. The Nusselt number, entropy generation, and friction factor have been discussed and analyzed detailly. It is found that as the Reynolds number enhances, the effect of inertial forces becomes more dominant. Furthermore, by increasing the porosity to 0.8, the Nusselt number decreases to a minimum value. Heat transfer enhancement by increasing Hartmann's number is less effective than adding nanoparticles. A more significant Hartmann number and larger nanoparticle volume fraction lead to more extensive performance evaluation criteria. It is also found that adding a magnetic field increases the friction factor. Adding nanoparticles to the pure water decreases entropy generation by heat transfer per unit volume