The right location of an individual wind turbine within a wind farm is important in order to gain its optimal power output. Due to the large area involved, an experimental study can be difficult and non-economical. This paper presents a methodology by which the location of downstream turbines can be estimated by using velocity pattern analysis. A wake structure of an isolated helical Savonius turbine with 90º twist angle is first evaluated by a Sliding mesh method incorporating Reynold Average (RANS) turbulence model Spalart Allmaras. The formation of vortices outside the wake is then observed. It was found that by placing a downstream turbine at the location of the strongest vortex occurrence, in this case within the area between 20º to 90º with respect to the advancing blade of the upstream turbine, produces an enhancement of power coefficient to the later. Repeating the same procedure for another downstream turbine also yields the same result. The last turbine of the line array always experiences the highest power coefficient of all. An application of the concept to a 9 turbine array in a V formation reveals an overall power improvement of 11%. However, placing the downstream turbine in other areas of weaker vortex shows insignificant improvement.

This paper presents the results of CFD analysis on a complex near optimized cooling channels of hot stamping die for automotive structural part. Near optimum design is acceptable since cooling channels design is limited by its machining constraints. The obje ctive of this evaluation is thus to determine the efficiency the cooling system by monitoring its cooling rate during 8 seconds of the quenching process. The die and blank were modelled as 3D volume mesh in a closed position thus ignoring the blank history data prior to the stamping operation. Temperature distribution representing hardness of the simulated final part is compared with the actual stamped component. The same procedure was validated against another structural component of different cooling channel design. The results show temperature pattern after 8 seconds can be used to predict harness distribution of the final part, thus indicating the viability of this method to be used in cooling system design.

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An optimum layout of turbines in a wind farm can be measured by a parameter called wind power density. This is essentially the power generated by the turbine per unit area. This paper attempts to demonstrate how the parameter could be increased by an oblique array configuration. In this numerical study, multiple helical Savonius turbines were used to compare the performances of different wind farm layout designs by using a finite element CFD solver. The optimum spacing between turbines was first determined for three turbine array configurations. It was then extended to a nineturbine array in V formation. Three wind farm configurations were considered namely all in clockwise (CW) or counterclockwise direction (CCW) and the other is a combination of CW and CCW direction. The wind power density for each configuration was then compared. The nine turbines arranged in V formation has improved its power density by 4 to 5 times when compared to nine isolated turbines in a wind farm.

This paper presents a design process of workstation with ergonomic features for University Kuala Lumpur MIDI Classroom. The workstation is expected to support body posture, with the aim to increase comfortability of a user usage for long periods in a class. Besides that, the workstation will ensure a conducive and responsive learning environment. Discomfort and an improper position can negatively affect overall health and productivity. A new design of workstation, which allows user to sit in ideal sitting position suggested by ergonomist and easy transition from one teaching mode to the next. The researcher has designed and developed a new workstation which has ideal ergonomic sitting working position and capable accommodate 50th percentile human size. These positions were used to evaluate the comfort of the workstation. Subjective evaluations, including comparison of the prototype and standard workstation setup, were carried out using human subjects and ergonomic principles. Result showed that the new workstation is much more comfortable, supporting the body in a balanced way. Users have the freedom to stretch and relax in different working positions before they feel any noticeable discomfort. As a result, it lets user sit for a longer period without strain, thus resulting in higher productivity and concentration in classroom.