Experimental study on viscosity and isobaric heat capacity of PEG 400 enhanced with TiO2 nanoparticles

Abstract

In the last years, a lot of research is committed to developing new heat transfer fluids for medium to high temperatures applications. This experimental analysis is dedicated to a less studied fluid, PEG 400 enhanced with titanium oxide nanoparticles, and started with suspensions manufacturing, morphology analysis and a strong discussion on viscosity, rheological behavior and isobaric heat capacity. Precisely, five suspensions of up to 2.5 %wt. TiO2 were analyzed through the entire experimental in terms of their behavior at ambient temperature and heating. Plus, viscosity was checked for possible hysteresis and the experimental revealed that this is almost absent for these nanocolloids, which is favorable for heat transfer applications, especially in heat exchange. The rheological tests revealed a non-Newtonian comportment for all of the samples, comportment that is more obvious when nanoparticles concentration increases. In terms of viscosity outputs, a normal fluidic behavior was noticed at heating, while the viscosity upsurges between 8 and 36 %, depending on nanoparticle concentration. Isobaric heat capacity tests demonstrated a decrease of up to 6.3 % for higher loaded nanocolloids and a relatively small variation with temperature, which is, somehow, in line with state of the art. As a conclusion, it may affirm that nanocolloids based on PEG 400 and oxides can be a good alternative for heat exchange applications.

Keywords

• PEG 400
• TiO2 nanoparticles
• Isobaric heat capacity
• Viscosity
• Rheology