Abstract: The transportation industry is no doubt a fast growing industry globally. In the recent years, the use of nano fluids have been proposed in the refrigeration and air-conditioning system as primary, secondary fluids and lubricants to enhance the performance of the system. This present study focuses on the use of TiO2 and SiO2 nano lubricants to improve the performance of the vapour compression system. Pure mineral oil was used as the base fluid and the performances were compared with that of the TiO2 and SiO2 nano lubricant using R600a refrigerant as the working fluids in the system. The result showed that R600a performed better in the nano lubricant compared to the base lubricant in terms of coefficient of performance, power consumption and the cooling capacity of the system.

• Publication Date: 24-Apr-2019
• DOI: 10.15224/978-1-63248-170-2-14
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Abstract: Numerical study has been carried out to determine the ultimate bearing capacity of circular footing on a sand layer of limited thickness underlain by a rigid rough base subjected to an eccentric vertical load. The sand layer for the numerical study was prepared at a relative density (Dr) of 69% using five different thicknesses, H. FE model was performed at H/B values of 0.3, 0.5, 1, 2, and 3 (B = diameter of footing). The load eccentricity ratio e/B varied from 0 to 0.15. The analysis was performed using an elasto-plastic hyperbolic model called the hardening soil (HS) model. Effect of the depth of rough rigid base and load eccentricity on bearing capacity was studied under eccentric vertical loading. Further, the failure mechanism under eccentric vertical loading has been studied. Numerical modeling results indicate that the bearing capacity and the depth of failure surface get modified when the rigid rough base is located at a shallow depth (H/B smaller than H/Bcr) from the base of t

• Publication Date: 24-Apr-2019
• DOI: 10.15224/978-1-63248-170-2-15
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• Downloads: 0