Computational Fluid Dynamics Investigation of Thermal Performance in Helical Tube Radiators Using Ethanol Coolant under Variable Outlet
DOI:
https://doi.org/10.63746/njtd.v23i1.4300Keywords:
Automotive radiator, CFD analysis, Ethanol coolant, Helical tubes, Heat transfer, Thermal performance, ANSYS CFXAbstract
This study investigates the thermal–hydraulic performance of a helical tube automotive radiator using ethanol as a coolant under varying outlet pressures. A three-dimensional CFD model was developed using ANSYS CFX 2021 R1 and validated using Dittus–Boelter and Darcy–Weisbach correlations. The analysis was conducted under steady-state turbulent conditions with a mass flow rate of 2.3 kg/s and inlet temperature of 371.75 K. The results indicate that outlet pressure significantly affects thermal performance. The maximum temperature drop of 12.58 K was achieved at 2.0 bar, while the minimum of 9.63 K occurred at 0.5 bar. However, the improvement from baseline (0.25 bar) to optimal condition is only 1.4%, indicating limited practical significance. Pressure drop remained nearly constant (~8.93 bar), leading to a pumping power requirement of approximately 6.5 kW. A comparative thermophysical analysis shows that although ethanol offers lower viscosity and reduced pumping resistance; its thermal conductivity and specific heat capacity are significantly lower than water-based coolants. This limits its intrinsic heat transfer capability. The study concludes that while ethanol can be used under specific conditions, its performance is strongly dependent on flow rate and system configuration, and it does not outperform conventional water-glycol coolants under identical operating conditions.
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