Convective heat transfer of nanofluids TiO₂/Thermo Oil XT 32 in concentric tube heat exchanger

This research was conducted to examine the heat transfer characteristic of nanofluids TiO₂/Thermo XT 32 oil on a concentric tube heat exchanger. TiO₂ nanoparticles with nominal diameter of 21 nm were dispersed in Thermo XT 32 oil as base fluid at three different particles concentration of 0.1%, 0.3%, and 0.5%, respectively. A straight horizontal stainless-steel tube of 1.2 m length, 0.012 m inner diameter, and 0.022 m outer diameter were used as a test section. Collecting data by varying the temperature of the heat transfer nanofluids and nanoparticle volume fraction. Nanofluids prepared using the method of two steps without the addition of a surfactant by using a magnetic stirrer for 1 hour then ultrasonic cleaner for 3 hours. The results of research conducted, the coefficient convection heat transfer of nanofluids TiO₂/Thermo XT 32 oil increases along with the addition of fraction volumes; this is due to the increased thermal conductivity of the fluid as well with the rise of temperature against nanofluids TiO₂/Thermo oil XT 32. So it is very worthy of nanofluids applied in industries related to heat transfer processes.