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Nanofluids generate considerable interest in increasing the heat transfer performance of a system, specifically as a coolant. A study of Aluminum Oxide (Al2O3) nanoparticles in water and ethylene glycol (60:40) mixture is conducted by using computational fluid dynamics (CFD) to investigate its potential by assuming a single-phase and constant thermophysical properties model. This study aims to analyze its heat transfer enhancement by using a theoretical properties model in several volume concentrations: 0.3%, 0.6%, 1.0%, and 1.5%. A straight tube geometry by neglecting its wall thermal conductivity is used under laminar conditions and constant heat flux and 293 K inlet temperature, compared with various Reynolds numbers. The model is validated using Shah Correlation, resulting 8% maximum deviation. The Einstein theoretical model fails to predict the viscosity properties resulted in more than a 10% deviation from the current experimental findings. Notwithstanding the theoretical prediction, the simulation observed that a 1.5% volume concentration increased higher heat transfer enhancement around 3%. [ABSTRACT FROM AUTHOR]

Tidal turbine is a horizontal axis turbine utilizing tidal energy to generate electricity while several existing studies related to the tidal turbine have been carried out, especially on the tidal turbine design to increase the turbine performance. The tidal turbine design is improved in various methods, namely augmenting a diffuser, modifying the diffuser angle, and appending a brim at the end of the diffuser as used in wind turbines with the aim of keeping vortex away from the tidal turbine outlet to minimize pressure drop. This study aims to compare the use of the brim by observing the level of effectiveness and the efficiency of the output power. The comparison is made by modeling the tidal turbine at four diffuser angles and the use of brim. The four diffuser angles were varied started from 10.43° to 35.97° with tidal current velocity around 0.7 m/s. The model is then analyzed by applying the computational fluid dynamics approach utilizing ANSYS application. It is then expected to obtain higher level of effectiveness and power efficiency of the tidal turbine by introducing the brim combined with diffuser augmentation. [ABSTRACT FROM AUTHOR]

In in-vivo bone tissue engineering, therapeutic efficacies are often unsatisfactory because the stem cells lose significant viability post-transplantation. The damaged cell may also present an unfavorable environment for cell growth. This means that cell transplantation would require the cells to be kept in a particular environment with substances that can support their survival, induce bioactivity, and enhance retention at the administered sites. This need drives the development of stem cells encapsulation in a biomaterial-based microcapsule. Our previous study has been conducted to encapsulate mesenchymal stem cells (MSC) in a feasible laboratory setting. It showed the survival of the MSC in the alginate system. However, higher throughput and uniform size of the encapsulated cells are needed. Therefore, this study introduces a Lab-on-a-chip setup to produce encapsulated stem cells as required quality. Here, an initial study on droplet generation was carried out using Computational Fluid Dynamics software. The study will use the volume of fluid methods with multiphase calculation taking oil as primary phase and water as a secondary phase. The CFD simulation shows that droplet size can be controlled at the range of 100-400 µm by varying the flow rate parameters. A comparative study also showed to confirm our result. This paper can be used for further studies in controllable droplet generation for stem cell encapsulation. [ABSTRACT FROM AUTHOR]