Nano fluid of lubricating oil for internal combustion engines was prepared by adding TiO2 sol as a source for Nano TiO2 particles. TiO2 sol was prepared via sol-gel route. The Nano sol was found to improve thermal conductivity, heat transfer and other physical properties of lubricants. The prepared TiO2 sol, with bright golden color, was added to the local lubricant oil (Al-Rasheed brand) with 2 vol.% of the oil.
The addition of TiO2 Nano sol to Iraqi oil increased significantly heat transfer and thermal conductivity of pure lubricant oil. The heat transfer increased by 38.4% with time lag of 25 min.
Also, other physical properties of Nano fluid oil were improved to fulfill the requirements of Iraqi specification (1197/2000) and as follows:
1- Viscosity form 274 to 368 Cp at 25o c
2- Pour point from -7 to -18.5 o c
3- Density from 0.90 to 0.95 g/cm3
4- Flash point from 164 to 232 o c
The originality in this work resides in the new combination of TiO2 – Nanosol with lubricating oil to produce Nano fluid which used successfully in this experiment.
Audience Take Away:
- It is a simple and facile liquid-liquid stable mixture with negligible phase or precipitation of particles for more than one year without chemical change of the nano fluid.
- The nano fluid was homogeneously mixed using magnetic stirring for 2 hours and was further mixed using high energy sonicator at 40 oC for another few hours to improvise the stability of the nano fluid without adding any additives.
- We observed 38.4% enhancement of the effective thermal conductivity in this method comparing with 33% enhancement reported by other researchers when TiO2 nano powder was used.
- The thermo-physical tests concluded that the prepared nano fluid was excellent comparing with plane engine oil.
- However, addition investigations are necessary to verify the impact of temperature and other variables, on the effective thermal conductivity of nano fluid.