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Contaminants are recently discovered at the joint of large piping system and causing defect to industrial product. A computational analysis can be used as a solution of the hydrodynamic contaminant removal without any modification needed. In this paper, the effect of heat is introduced to analyze the heat transfer and flow field in a channel with cavity heated at the bottom sides coupled with different shape of cavity. The cavity shape used comes with three shapes i.e. square, triangle and semicircle. The process of fluid dynamic in a cavity is modeled via numerical solution of the NavierStokes equations using Cubic Interpolated Profile (CIP) method. By using the simulation of hydrodynamic contaminant removal, the flow of streamlines and vortices pattern was investigated in the cavities. In order to remove all of the contaminant, hydrodynamic need to take part in this simulation which is flow from the inlet of the channel and create vortices to remove it from the cavities. The result shows that the percentage of contaminant removal is higher for semicircle cavity with higher Grashof number. The result also indicates that vortices formation is highly dependent on the cavity geometry and creates a buoyancy effect.

Research on the waste energy and emission has been quite intensive recently. The formation, venting and flared the Boil-off gas (BOG) considered as one of the contribution to the Greenhouse Gas (GHG) emission nowadays. The current model or method appearing in the literature is unable to analyze the real behavior of the vapor inside Liquefied Natural Gas (LNG) tank and unable to accurately estimate the amount of boil-off gas formation. In this paper, evaporation model is used to estimate LNG Boil-Off rate (BOR) inside LNG tank. Using User Define Function (UDF) hooked to the software ANSYS Fluent. The application enable drag law and alternative heat transfer coefficient to be included. Three dimensional membrane type LNG cargos are simulated with selected boundary condition located in the United States Gulf Coast based on average weather conditions. The result shows that the value of BOR agrees well with the previous study done with another model and with International Marine organization (IMO) standard which is less than 0.15% weight per day. The results also enable us to visualize the LNG evaporation behaviors inside LNG tanks.

The creation of internal combustion engine is a significant milestone in power engineering world which simplified high mechanical energy demand jobs like moving vehicle and machinery. Even though the internal combustion engine gives lot of advantages, however, this type of engine is incapable to convert the heat energy from fuel combustion to the mechanical energy efficiently. Small capacity engine e.g. motorcycle engine having the power conversion efficiency between 25-30%. Therefore, alternative power source is required to support the internal combustion engine in order to increase the overall system efficiency. These phenomena give encouragement to implement the hybridization process. This is to increase the system efficiency in transferring power to the wheel. Hybridization processes e.g. flywheel as secondary power source can increase power transfer efficiency between 30%-80%. Hence, the purpose of this research is to develop the mathematical model of the power transfer efficiency of flywheel hybrid motorcycle by using back trace simulation method. This model will record the amount of energy use in acceleration phase of the driving cycle. Subsequently, the efficiency ratio of motorcycle power transfer is calculated and comparison of those ratios between the conventional motorcycle and the hybrid motorcycle is made. The outstanding results show that the hybrid motorcycle is capable to conserve the energy used up to 36% compare to the conventional motorcycle that wasted energy up to 200%. As a conclusion, flywheel as the secondary power source is capable to supply enough energy to propel the motorcycle forward.

An investigation of water-based reciprocating triplex piston pump was conducted to propose a low cost solution for the substitution of the traditional oil hydraulics to water hydraulics. Triplex pumps used in this investigation as the water hydraulics require continuous pumping. These pumps are capable of handling a wide range of fluid types, including corrosive fluids, abrasive fluids, and slurries containing relatively large particulates. Thus, an evaluation of the triplex pump using a simple simulation process that focuses on the volumetric efficiency has been conducted in order to understand its ability in energy-efficient system. In this paper, the results of a simulated study of a positive displacement triplex piston pump are presented. The result concludes that the use of water is relatively efficient if the slip factor is maintained to 0.003, with the system pressure is set from 10 to 40 bar.