The effect of TiO2/ethylene glycol-based nanocoolant on the pollutant emissions from a diesel passenger van at Quito ambient conditions

Abstract

In recent years, nanofluids have captured great attention due to their enhanced thermal properties in comparison to conventional pristine base fluids. Among them, TiO2 nanofluids have shown outstanding improvements on heat exchange transfer and thermal conductivity at extremely low TiO2 volume fractions. However, there is a lack of research on nanofluid applications in cooling systems of internal combustion engine vehicles and their influence on the pollutant emissions from these mobile sources. Thus, in this work a nanofluid, composed of 0.5 vol.% TiO2 nanoparticles and a commercial ethylene glycol-based coolant, was prepared to assess their effect on CO2, CO, NOx, hydrocarbon (HC) and fine particulate matter (PM2.5) emissions from a diesel passenger van under the IM-240 cycle, at Quito ambient conditions (2800 m.a.m.s.l.). Therefore, the use of TiO2-based nanofluids allowed improving the thermal efficiency of the engine, as demonstrated by the rise of CO2 emissions (2%), along with the consequent reduction of CO, HC and mainly PM2.5 up to 16, 17 and 60%, respectively. The substantial decrease in PM2.5 by using TiO2-nanocoolant could drop the impact of diesel vehicles on human health, particularly on cardiovascular and respiratory diseases.