Thermophysical Properties of Vegetable Oil-Based Hybrid Nanofluids Containing Al2O3-TiO2 Nanoparticles as Insulation Oil for Power Transformers

Abstract

The massive demand in the electrical power sector has resulted in a large demand for reliable, cost efficient, and environmentally friendly insulation oil to reduce the dependency on mineral oil. The hybridization of nanoparticles in vegetable oil is a novel method to enhance the thermal properties of vegetable oil. This study focuses on the experimental investigation of the thermophysical properties of coconut oil, soybean oil, and palm oil-based hybrid nanofluids suspended with Al2O3-TiO2 nanoparticles at a mass concentration of 0.2, 0.4, and 0.6%. The ratio between Al2O3 and TiO2 nanoparticles was maintained constant at 50:50. The main purpose of the study is to evaluate the thermal conductivity, dynamic viscosity, and density of different vegetable base oils suspended with Al2O3-TiO2 in the temperature range of 30 to 60 °C. The influence of temperature on the augmentation of thermophysical properties for different vegetable oil-based hybrid nanofluids is investigated experimentally. The experimental results for thermal conductivity for the three types of base fluids show that the effect of nanoparticle mass concentration in thermal conductivity enhancement is less significant for temperatures more than 50 °C. The palm oil with a 0.6% Al2O3-TiO2 nanoparticle concentration exhibited the highest thermal conductivity with a 27.5% thermal conductivity enhancement relative to the base oil. The effect of nanofluid temperature on density and viscosity augmentation is more distinct compared with the impact of Al2O3-TiO2 nanoparticles concentrations. Among all three types of hybrid nanofluids, palm oil based nanofluids were found to have superior thermophysical properties compared with coconut oil and soybean oil, with the highest thermal conductivity of 0.628 W/m·k and lowest viscosity of 17.772 mPa·s.

Experimental evaluation of biolubricant with additive nanoparticle calcium carbonate (CaCO₃) from scallop shell waste as cutting fluids using minimum quantity lubrication (MQL) in CNC milling process

“…Therefore, these results signify that the higher the mass fraction of nanoparticles addition to the base oil increases the density. In this density test, CaCO 3 nanoparticles have a role in changing fluid properties, where the addition of CaCO 3 nanoparticles to the base fluid can increase the density of the cutting fluid sample, it is because the CaCO3 nanoparticles mixed can increase the amount of substances contained in a unit volume of base fluid [66].…”

Performance of Hybrid Nanofluids of Mineral Oil and Vegetable oil based Ester

“…These insulating liquids are derived from both seeds and flowers. VOs are the subject of several studies in an effort to use them as insulating oils in transformers and create eco-friendly environments [3]. VOs are thought to be more nature-friendly liquids due to their high biodegradability (>95 %), high flash and fire points (both >300 °C), and lesser flammability [4].…”

Techno-economic and environmental analysis of a hybrid PV/T solar system based on vegetable and synthetic oils coupled with TiO2 in Cameroon

“…Furthermore, a comparative study presenting the effect of each NP with different types of base fluids is not presented and the effect of the thermophysical properties of these oils on the electrical consumption of the pump is not also evaluated in the previous studies. A thermophysical evaluation of three types of vegetable oils including coconut, soybean and palm oil suspended with hybrid nanoparticles was carried out by Vignesh et al [ 28 ]; Among these fluids, palm oil-based NFs were found to have better thermophysical properties. However, a study over an annual period and not just a daily period of these nanofluids based on vegetable oils could be very conclusive.…”