Research of geometrically distinct automobile radiators in terms of thermal-hydraulic characteristics

Abstract

The fin-and-tube heat exchangers are traditionally used in the automobile cooling system to maintain a proper function and service life of an engine and its components. In the study, the effect of coolant and radiator mileage on thermal–hydraulic characteristics of radiators was investigated. Two types of automobile radiators with different heat exchange areas, mileage, number and size of fans, tube configurations, and coolant mileage were experimentally studied. The local and average Nusselt number of the tubes and fins, heat flux, pressure drop, and efficiency index JF were evaluated based on the numerical studies where the turbulent flow was solved by the k-ω SST model using the ANSYS Fluent software. The shortest cooling time was achieved at the new radiator II with the coolant mileage of 0 km (4 min), while the longest one was achieved at the old radiator II with the coolant mileage of 50,000 km (8.5 min). The radiator II with two fans achieved half the time of cooling when running both fans compared to the only one. The studied range of the coolant and radiator mileage do not have any significant effect on the fault-free operation of the engine cooling system. The efficiency index JF for the new radiator I with the coolant mileage of 0 km is 0.86 – 1.90% higher for the tubes and 0.42 – 1.22% higher for the fins compared with the other investigated radiator and coolant mileages.