Experimental analysis of the thermohydraulic performance of graphene and silver nanofluids in automotive cooling systems

• Published in: International journal of heat and mass transfer Vol. 132; pp. 375 - 387
• Main Authors: Cárdenas Contreras, Edwin Martin, Oliveira, Guilherme Azevedo, Bandarra Filho, Enio Pedone
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.04.2019; Elsevier BV
• Subjects: Automotive parts; Cooling rate; Cooling systems; Correlation analysis; Ethylene glycol; Flow velocity; Graphene; Heat transfer; Heat transfer rate; Mass flow; Nanofluid; Nanofluids; Nanoparticles; Pumping; Pumping power; Radiator; Radiators; Thermophysical properties; Wind tunnels; Performance; Radiator; Nanofluid; Pumping power; Heat transfer rate
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2018.12.014

•Experimental measurements of thermophysical properties of nanofluids.•Performance evaluation in terms of nanofluid concentration, temperature and mass flow.•Thermal-hydraulic performance tests conducted in a temperature range from 55 to 85 °C.•New experimental data of Graphene and Silver nanofluids in a car radiator. This paper presents an experimental investigation of the thermohydraulic performance of nanofluids, composed of graphene and silver nanoparticles with a binary mixture of equal parts of water and ethylene glycol (50:50 vol%) as a base fluid, in automotive radiators. The nanofluids were prepared by high pressure homogenization method with volumetric concentrations of 0.01%, 0.05% and 0.1%. The thermophysical properties were measured experimentally and compared with correlations and others results of similar research found in the literature. The nanofluids were tested in an automotive radiator installed in a wind tunnel, simulating the operation of an automotive cooling system. The experiments were conducted at mass flow rates between 0.08 and 0.11 kg/s, with coolant inlet temperatures between 55 and 85 °C. The air velocity on the radiator was kept constant at 2.1 m/s. The heat transfer rate and the pumping power of the fluids tested were determined under the test conditions stipulated. With regard to the pumping power at high temperatures and mass flow rates, the nanofluids showed increases up to 4.1%. The silver nanofluids produced an increase up to 4.4% in the heat transfer rate, while the graphene samples demonstrated a decrease in thermohydraulic performance when compared with the base fluid.