Numerical Investigation of the Effect of Adding Nanoparticles to Helicopter Motor Oil

In this paper, the effects of added nanoparticles to oil with the aim of improving heat transfer were investigated. At first, thermophysical characteristics of helicopter oil (MIL-L-23699) were measured by cooperation of chemical laboratory of Iran Helicopter Support and Renewal Company (PANHA). Then, by collecting other data, geometry of the problem was produced and gridded through the use of Gambit software and was transmitted to Ansys Fluent 17.2 for simulating the flow and heat transfer. The single-phase model and control volume technique have been used to solve this problem. The results reveal that by adding nanoparticles to helicopter oil, thermal properties, such as Nusselt number, considerably improve in comparison with pure oil. However, the improvement of heat transfer process for gold-oil nanofluid is more than the other nanofluids. Comparing the results also shows that adding nanoparticles to the base oil causes a slight pressure change, which has no special effect on nanofluid pumping. The results indicate that by increasing Reynolds number, Nusselt number and static pressure increase and friction coefficient decreases. It is also observed that in a constant Reynolds number, by increasing working temperature, Nusselt number, friction coefficient, and static pressure decrease and temperature increases. Therefore, adding nanoparticles to helicopter oil would lead to the improvement of heat transfer properties, better cooling of the size of engine, shrinking the engine lubrication system, the ability of tolerating high loads, the ability of flying at higher altitudes, and eventually the enhancement of power and efficiency of the engine.