An Experimental Study on the Simultaneous Effect of Nanofluid and Tube Insert on the Thermal Performance of an Automobile Cooling System


1 Department of Mechanical Engineering, Lorestan University, Khuramabad, Iran

2 Department of Mechanical Engineering, Islamic Azad University, Doroud Branch, Doroud, Iran


In this research, an experimental study is conducted to investigate the effect of simultaneous use of tube insert and nanofluid on the thermal performance of the automotive cooling system (radiator). Al2O3-water based nanofluid is used and the flow regime is laminar (Reynolds 1000-1800). For this study, an experimental automotive cooling system is designed and built. Thermal performance of Al2O3-water nanofluid at three concentrations of 0.1, 0.2 and 0.4% weight fraction of Al2O3-water nanofluid compared to water is monitored by variations of flow rate. In this research, a tube insert with a steel wire rod and a sine profile inside the radiator tube is used as a turbulent-maker. The results show that the sole use of nanofluid, without a tube insert inside the radiator, increases the heat transfer coefficient by about 11%, and the use of a tube insert together with distilled water increases heat transfer coefficient by about 35%. Finally, the use of tube insert together with Al2O3-water based nanofluid at their best mass concentration increases heat transfer coefficient by about 56%.