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The performance of a domestic refrigerator with the addition of nanoparticles in the lubricant was experimentally investigated. Different sizes of nanoparticles of Al2O3 and TiO2 were added to the polyolester (POE) oil in two different volume concentrations (0.05 and 0.1 vol.%). Energy consumption tests and freeze capacity tests were then performed on the refrigerator. The investigation results showed that the refrigerator worked normally and safely with the nanolubricants. The results of the experiments indicated that the refrigerator performed better with nanolubricants as compared to pure POE oil. The COP of the systems was increased by 19% and 22% when 0.05% and 0.1% Al2O3 nanoparticles were added to the POE oil respectively. The system with 0.1% volume concentration of Al2O3 and TiO2 nanoparticles added to the POE oil consumed 27.73% and 14.19% less energy as compared to the pure POE oil system. Hence, this study showed that the addition of nanoparticles in the lubricant oil of the refrigerator is practical and it enhanced the performance of the refrigerator

This paper discusses the design and development of the Moderate and Intense Low oxygen Dilution (MILD) combustion burner using Computational Fluid Dynamics (CFD) simulations. The CFD commercial package was used to simulate preliminary designs for the burner before the final design was sent to the workshop for fabrication. The burner is required to be a non-premixed and open burner. To capture and use the exhaust gas, the burner was enclosed within a large circular shaped wall with an opening at the top. An external EGR pipe was used to transport the exhaust gas which was mixed with the fresh oxidant. To control the EGR and exhaust flow, butterfly valves were installed at the top opening as a damper to close the exhaust gas flow at a certain ratio for EGR and exhaust out to the atmosphere. High temperature fused silica glass windows were installed to view and capture images of the flame and analyze the flame propagation. The burner simulation shows that MILD combustion was achieved for the oxygen mole fraction of 3-13%. The final design of the burner was fabricated and ready for the experimental validation.

The forced convection heat transfer coefficient and friction factor are determined for the flow of water and nanofluid in a vertical packed bed column. The analysis is undertaken in the laminar and transition Reynolds number range. The column is filled with spherical glass beads as the bed material. The heat transfer coefficients with Al 2 O 3 nanofluid increased by 12% to 15% with the increase of volume concentration from 0.02% to 0.5% compared with water. The experimental values of axial temperature are in good agreement with the NTU-ε method proposed by Schumann's model.

This paper presents an experimental investigation on the coated carbide cutting tool performance of aluminium alloy AA6061-T6 machining through end mill processes using the minimum quantity lubrication (MQL) technique. The process parameters including the cutting speed, depth of cut and feed rate are selected. The effect of the base fluid ratio (water: EG) to the hybrid nanocoolant was investigated in this experiment. The hybrid nanocoolant with 80:20 of volume concentration up to 0.1% was prepaid with a 21 nm particle size of TiO2 and 10-30 nm ZnO nanoparticle for measurement purposes and tested at cnc end milling machines. The analysis of the variance method is utilised to validate the experimental data and to check for adequacy. The response surface method was used to develop the mathematical models and to optimise the machining parameters. It is observed that the material removal rate depends significantly on the depth of cut and feed rate, followed by the spindle speed. The results can be used as an example of the minimum quantity lubricants (MQL) technique applied to the machining of aluminium alloys, providing economic advantages in terms of reduced the machining costs and better machinability.