Jouvan Chandra Pratama Putra

Simulation of Room Airflow Using Comsol Multiphysics Software

Airflow in a room can be supplied both through natural mean and also by the helps of mechanical ventilation. Natural ventilation is more sustainable compared to mechanical system; however natural ventilation, it may not be sufficient to fulfil the need of ventilation for a specific room. This study presents simulation works carried out regarding to the airflow movement in a room due to mechanical ventilation. The measurement of air velocity was taken using Davis anemometer at random point in the room. The measured air velocity then used as an input in simulation work which used Comsol Multiphysics software. The simulation process begins by building up geometry of the room, assigning constant parameters, meshing the geometry of the room, and finally run the solver analysis. The results from simulations indicate that the air distributions in the room are below ASHRAE standard. This is due to the airflow distribution from the airflow injection of air-conditioning system is not well distributed. The simulations results are validated with the measured value and found that the percentage differences between the simulated and measured values are within the range of 3 - 10 %. Keywords: Simulation, Airflow movement, Mechanical ventilation, Comsol Multiphysics software

Evaluation of reverberation time of class room

The reverberation time is considered as a main parameter that defines the function of room. It can be calculated based on the analytical and simulation methods. However, these two methods generated the discrepancy value and it affects to the treatment that should be considered to improve the acoustic condition. This paper aimed to identify the possibilities of discrepancy that resulted between analytical and simulation methods. The analytical approach used three formulas such as SABINE, NORRIS-EYRING, and MILINGTON-SETTE. Additionally, for the purpose of simulation approach, this study used Autodesk Ecotect software. The parameters required to these two methods were area, volume, coefficient absorption for each material assignment, and surface area of each section that receive the sound wave. The results indicated that there is a high discrepancy between the analytical and simulation results, which is in the range of 5.19% to 68.51%. Since the analytical method do not consider which part surface area that receives less of sound wave and vice versa, then the discrepancy appears in the final results between these two methods. Additionally, the findings show that there are four points that considered as the main contributor that leads to the discrepancy between analytical and simulation methods, namely internal temperature of room, humidity of room, coefficient absorption, and complexity of building design.The reverberation time is considered as a main parameter that defines the function of room. It can be calculated based on the analytical and simulation methods. However, these two methods generated the discrepancy value and it affects to the treatment that should be considered to improve the acoustic condition. This paper aimed to identify the possibilities of discrepancy that resulted between analytical and simulation methods. The analytical approach used three formulas such as SABINE, NORRIS-EYRING, and MILINGTON-SETTE. Additionally, for the purpose of simulation approach, this study used Autodesk Ecotect software. The parameters required to these two methods were area, volume, coefficient absorption for each material assignment, and surface area of each section that receive the sound wave. The results indicated that there is a high discrepancy between the analytical and simulation results, which is in the range of 5.19% to 68.51%. Since the analytical method do not consider which part surface area that...

A study of indoor air quality of public toilet in University's building

This paper presents a study of IAQ in toilets located in the Faculty of Civil and Environmental Engineering building, Universiti Tun Hussein Onn Malaysia (UTHM). This study was conducted to determine the level of gas pollutants exist in the male and female toilets. The important IAQ parameters considered in this study are SO2, NO, and CO2. The measurements were conducted during break hour and taken using air quality monitoring. The result indicated that SO2 exceeded the threshold value and this could have adverse effect on inhalation such as asthmatic. Finally, the existing SO2 was affected by mechanical ventilation mode, while the existing CO2 was more generated in female toilet.