Mohd Irwan Mohd Azmi

Design approach for tunable CMOS active inductor

A design approach for differential CMOS active inductor with a self-resonant frequency around 1.58GHz-3.98GHz is presented. The architecture is based on a differential gyrator-C topology to transform intrinsic capacitance of a MOSFET to the emulated inductance. Due to high power consumption of active inductor, only a current source is used. This design has the capability to tune the inductor and Q-factor values from 10nH-60nH and 20-60 respectively. Furthermore, a technique is proposed to ensure smaller inductance value can be achieved with smaller power consumption and die area.

The effect of contact angle on triangular shape interrupted microchannel heat sinks performance

The effect of different contact angle on triangular shaped interrupted microchannel performance was studied by simulation using FLUENT software. The investigated effects were pressure drop and platinum film temperature. The flow in microchannel is laminar and single phase. Water was used as the working fluid and the interrupted microchannel is made of silicon. A thin platinum film plate was deposited to provide uniform heat flux. The geometry dimension of the heat sink is 30 mm in length, width of 7 mm and the thickness of 0.525 mm. The chosen contact angles that were investigated are 48.13°, 51.27° and 58.48°. From the simulation result, pressure drop and thermal dissipation is the highest for contact angle 58.48° and 48.13° respectively. Reducing the contact angle reduces the pressure drop and increases the thermal dissipation.

Free convection in square cavity driven by discrete three source-sink pairs on one sidewall

Lattice Boltzmann method (LBM) was applied to predict fluid flow and heat transfer characteristics of free convection in a two-dimensional square cavity driven by three discrete source-sink pairs on one vertical sidewall. The size of sources and sinks was L/6. The arrangement of the sources and sinks were alternately located. Simulations were conducted at Rayleigh number 103 to 105. The characteristics were represented by streamlines and isotherms. It was found that the solution is comparatively acceptable with other previous study applying conventional approach.

Preliminary studies of airflow around vehicle front windscreen

In this project, simulation of air flow around vehicles frontal windscreen area was carried out. The vehicle models that had been chosen for this project were models from the national car manufacturer. ANSYS CFX software was used to run the simulation. Comparison of flow patterns and the velocity distribution were made for the corresponding vehicle models. The speed of the flow was set to be 90 km/h in the simulation. The main objective of this study is to obtain the flow pattern around a vehicle windscreen. The second objective is to determine the velocity distribution on the vehicle windscreen and factors affecting the velocity distribution. It was found that there are differences in term of flow patterns and velocity distribution with respect to the windscreen inclination angle.

Mesoscale simulation of natural convection in square cavity driven by discrete two source-sink pairs on one sidewall

Lattice Boltzmann method (LBM) was applied to predict fluid flow and heat transfer characteristics of natural convection in a two-dimensional square cavity driven by two discrete source-sink pairs on one vertical sidewall. The size of sources and sinks was L/4. The arrangement of the sources and sinks were alternately located. Simulations were conducted at Rayleigh number 103 to 105. The characteristics were represented by streamlines and isotherms. It was found that the solution is comparatively acceptable with other previous study applying conventional approach.