Muhammad Azzam Ismail

Assessing the allowable daylight illuminance from skylights in single-storey buildings in Malaysia: a review

AbstractA skylight system casts uniform levels of natural light over an area with minimum obstruction either internally or externally. In tropical climates, especially near the equator, the levels of solar radiation and conditions of sky appearance represent the main limitation in this region. In Malaysia, the application of skylight systems to single-storey buildings is limited because of environmental constraints that discourage its adoption. Understanding the allowable level of daylight in an indoor environment is crucial. Many standards, guidelines, and studies have provided various levels, but the desired level is still under debate. Therefore, this research aims to review and evaluate the allowable useful illuminance of daylight in the indoor environment from a skylight in single-storey buildings (used for office work) under Malaysian sky conditions. This study provides a comprehensive review of previous research on understanding daylight illuminance and Malaysian sky conditions. Based on this compr...

Effective use of hybrid turbine ventilator to improve thermal performance in Malaysian tropical houses

An efficient design approach that involves extracting heat build-up in tropical buildings is a means to reduce total dependency on air-conditioning systems. The hybrid turbine ventilator can be regarded as a development technique to address this issue. However, identifying its efficient application in buildings remains questionable. This study aims to develop the research on the hybrid turbine ventilator for the establishment of energy-efficient designs in houses by evaluating its effective use in specific space volume based on several empirical comparisons. The performance of passive and hybrid turbine ventilators in attic space, room, and (attic space + room) with opened and closed windows was compared. The study was conducted in an actual building model, and data were collected onsite with a data acquisition system. The objective was achieved by investigation, and the findings can be used to identify the levels of heat build-up in each strategy. Examination of thermal performance confirmed the appropriate use of the hybrid turbine ventilator in Malaysian landed houses. Practical application :This research contributes directly to energy efficient design in tropical buildings. The outcomes inform a better decision on the effective use of hybrid turbine ventilator in low-rise buildings. The study provides ample evidence on the great potential of using hybrid turbine ventilator by developing its investigation in tropical architecture. The study will assist engineers and architects to evaluate hybrid turbine ventilator performance effectively.

Review of Thermal Performance: A Terrace House in Melaka, Malaysia

A field study of residents’ thermal comfort in a naturally ventilated intermediate single storey terrace house was carried out at Merlimau, Melaka. An intermediate single storey terrace house was chosen as a case study and indoor thermal condition measurements were recorded for three days. The indoor ambient temperature, relative humidity and air speed were measured using on-site monitoring equipment to evaluate the thermal performance of this house. A questionnaire survey was also conducted involving all occupants to determine their thermal comfort perception of the same case study house. The aim of this study is to analyse the indoor thermal condition of an intermediate single storey terrace house in order to propose architectural features to climatically adapt to the local climate. In naturally ventilated condition, results showed that this house is thermally uncomfortable and the indoor thermal condition was between 2.7°C to 5.9°C higher than suggested temperatures stipulated in ASHRAE Standard 55. Consistently, five out of eight occupants or less than 80% of occupants voted the house as thermally acceptable according to ASHRAE Standard 55.

Building Energy Index and Students’ Perceived Performance in Public University Buildings

Numerous studies have shown that students’ learning experience is closely associated with the physical comfort level of their teaching and learning environment. The different strategies or allocation of air-conditioning, mechanical ventilation (ACMV) and lighting systems contribute greatly to the energy performances in the buildings. This study explores the relationship between electricity consumption of the academic buildings of a public university in an urban context and its students’ perceived performance. It seeks to find the answer patterns from unsuspected subjects; whether there is a difference between a lower energy-use building and a higher energy-use building. To achieve the objective, the study adopts the quantitative method of assessing students’ perceived performance through questionnaire survey. The questionnaires, adopted from Building Use Studies, UK, were distributed randomly through convenience sampling to students from two academic buildings in the campus. Both buildings were selected through purposive sampling method with specific inclusion and exclusion criteria. Subsequently, power and energy logger was installed into the same buildings to monitor electricity consumption at specific intervals. For comparison, building energy index (BEI) for each building was calculated. The study found that the building that scored higher in students’ performance, also has higher calculated BEI. As control for indoor comfort account for more than half of the total electricity consumption, the result suggested that electricity consumption influences students’ performance positively. The study also revealed that both buildings’ calculated BEI were lower than recommended by many standards. This suggests that these buildings have extremely high potential of achieving green building status. If executed properly, the university campus, which equates the size of a small city, may achieve green campus status sooner than expected and may lead others in the flagship project towards a low-carbon university campus.

Airfoils Aerodynamic Performance Analysis in Heavy Rain

Heavy rainfall greatly affects the aerodynamic performance of the aircraft. There are many accidents of aircraft caused by aerodynamic efficiency degradation due to heavy rain. In this paper we have studied the heavy rain effects on the aerodynamic efficiency of NACA 64210 and NACA 0012 airfoils with cruise and landing configuration. For our analysis, CFD method and preprocessing grid generator are used as our main analytical tools, and the simulation of rain is accomplished via two phase flow approach named as Discrete Phase Model (DPM). Raindrops are assumed to be non-interacting, non-deforming, non evaporating and non spinning spheres. Both cruise and landing configurations of airfoils exhibited significant reduction in lift and increase in drag for a given lift condition in simulated rain. Our results are in good agreement with the experimental results. It is expected that the quantitative information gained in this paper will be useful to the operational airline industry and greater effort such as small scale and full scale flight tests should put in this direction to further improve aviation safety.