Thermal performance analysis of a cross-flow automotive radiator under variable air and coolant flow
|
Full Text |
Pdf
|
|
Author |
Sanjay Mitkari
|
|
e-ISSN |
1819-6608 |
|
On Pages
|
171-179
|
|
Volume No. |
21
|
|
Issue No. |
3
|
|
Issue Date |
April 10, 2026
|
|
DOI |
https://doi.org/10.59018/022627
|
|
Keywords |
radiator, cross flow heat exchanger, convective heat transfer, coolant.
|
Abstract
The study examines the thermal performance of a cross-flow automotive radiator typically used in internal combustion engine vehicles, where 8-30 kW of heat must be dissipated under varying operating conditions. Radiator cooling efficiency primarily depends on air velocity (1-6 m/s) and coolant flow rate (0.05-0.3 kg/s), with air-side management exerting the strongest influence. Experimental analysis showed a maximum coolant-side heat transfer rate of 26.25 kW, with Reynolds numbers between 16,650- 28,000 yielding a convective coefficient of 22.49 kW/m²K. On the air side, Reynolds numbers of 217-1,520 correspond to a heat transfer coefficient of 168 W/m²K and a peak heat flow of 23.8 kW. The overall heat transfer coefficient reached 167 W/m²K. Coolant temperatures decreased significantly along the radiator core, with low flow rates achieving large temperature drops (90°C to 64.3°C), while higher flow rates enhanced total heat removal through increased turbulence. Variable air velocity from 1 m/s to 5 m/s markedly improved convective heat transfer, confirming the dominance of air-side effects. System-level analysis highlights that, since pump flow depends on engine speed, variable-speed fan control provides the primary means of adjusting heat rejection in real time, improving thermal efficiency and reducing energy consumption in modern automotive cooling systems.
Back