Comprehensive parametric study and sensitivity analysis of automotive radiators using different water/ethylene glycol mixtures: Toward thermo‐hydraulic performance and heat transfer characteristics optimization

Abstract

Automotive radiators are primarily utilized in vehicles to dissipate the heat generated by the engine block into the surrounding. Utilizing coolants with superior thermophysical properties reduces the engine power consumption and improves the cooling engine performance. Comprehending the correlation between coolant characteristics and its thermohydraulic behavior is essential for advancing this innovative cooling technology. This investigation introduces a detailed parametric study of an automotive radiator using diversified coolant mixtures. Ethylene glycol (EG)/water mixtures, namely, (40:60), (50:50), and (60:40) are utilized as a coolant. The influences of the operational mechanism parameters, that is, inlet coolant temperature, intake air temperature, airflow rate, coolant flowrate, and coolant mixture ratio on the effectiveness, heat transfer, and fluid flow characteristics of the radiator are investigated. A thermohydraulic coupled model, based on the effectiveness‐NTU and thermal resistance theories, are developed for simulation of the investigated radiator. The outcomes revealed that the heat transfer rate is more significantly influenced by the inlet temperatures of the coolant and air than by the flowrate. Findings reveal optimal conditions for radiator design to be a coolant mixture of (40 EG:60 Water), coolant mixture Reynolds number of 1087.5, air Reynolds number of 2175, 11°C air‐intake temperature, and 94.25°C coolant mixture temperature for engine cooling maximization. The findings also indicated optimum mixture yielded the maximum advantage ratio (AR) and heat transfer with lowest pumping power, which achieved 7.94% and 19.30% higher AR compared to (50:50) and (60:40) mixture solutions, respectively. From energy consumption reduction prospective, the optimal EG/water coolant mixture results in a reduction in pumping power by 25.11% and 49.77%, compared to the (50:50) and (60:40) mixtures, respectively, under the same optimal operating conditions. Conclusively, the optimized automotive radiator design explored in this study offers a promising approach to improving vehicle technology and increasing cooling efficiency in internal combustion engines.