Lim Chin Haw

Case study of wind-induced natural ventilation tower in hot and humid climatic conditions

This paper investigates the performance of a wind-induced natural ventilation tower through an empirical analysis in hot and humid climatic conditions. There are mainly two methods for inducing natural ventilation; namely stack ventilation and wind-induced ventilation. Due to the relatively lower difference between the indoor and outdoor temperature in hot and humid conditions, stack ventilation method alone is rendered insufficient to create desirable air flow between outdoor and indoor building environment to achieve comfort and indoor air quality for the building occupant. Hence, wind-induced ventilation method can be used to achieve the desired air flow rates and improve the indoor air quality for the building. This study revealed that at external wind speed of 0.1m/s, the aerodynamic inverted airfoil roof geometry on the wind-induced natural ventilation tower is able to generate extraction air flow rate of 10,000m3/h with average of 57 ACH to provide comfort and indoor air quality to the internal building environment in hot and humid climatic conditions.

Review of Building Energy Efficiency in the Hot and Humid Climate of Malaysia

Globally, environmental concerns and the progressively increasing high cost of energy have resulted in renewed interest in alternative forms of energy conservation and efficiency. The aim of this study is to describe various energy policies that the government of Malaysia has been adopted in order to ensure long-term reliability and security of energy supply for sustainable social economic development in the country. Improved living standards in developing nations have led to higher demand for energy, which requires nations to review their energy efficient strategies. While a significant portion of the total primary energy is consumed by buildings in developed nations, developing nations like Malaysia are proactively addressing the energy consumption issue. This review describes the standards and energy efficient codes for buildings, introduces low-energy building concepts and provides information on energy consumption of buildings in Malaysia. Alternative energy options like biomass, solar, wind and mini-hydro energy to ensure reliable, sustainable and secure supplies of energy in this country are considered.

Effects of urban canyons and thermal comfort in the Persian Gulf region

Accessibility to thermal comfort spaces for citizens and urban outdoor activities could be one of the main goals of urban designers. The objective of this paper is to conduct a comparative study on two different urban fabrics, using thermal comfort and Computational Fluid Dynamics (CFD) methods. Results relate the effects of urban canyons orientation on variation of the microclimate factors and consequently, on the thermal comfort situation in the hottest period of the year. The results indicate that traditional urban fabric is more thermally comfortable than the new residential urban fabric. According to the field measurements, thermal comfort calculation, and wind simulations, the canyons with North-South direction represent a better orientation for air circulation benefiting from sea breezes as compared to other canyon orientations. The result will throw light for the urban designers and policy makers of hot and humid climate in the Middle East.