Index Terms-Evaporative cooling, effectiveness, dew point, dry bulb temperature.

This paper traces the evolution of housing typologies in four major cities in the Gulf region, namely Doha, Dubai, Abu Dhabi and Manama. The study reviews the formation and historical events in the region, which had a significant impact on new social as well as economic realities and consequently evolving housing types during the last two centuries. The methodological approach is based on reviewing a number of case studies representing local housing typologies throughout distinctive historic periods which were categorized in four periods: the post-nomadic, traditional, modern, and contemporary. The main objective is to identify the process of transformation by applying a comparative assessment of the different periods in order to examine continuities or ruptures between them. Thus, particular layout elements were analysed and compared. Conclusions are drawn to underline contemporary challenges while offering projections for future housing typologies in the selected cities and other similar ones

Abstract-The paper presents a computer model and experimental results of a sub-wet bulb temperature evaporative cooling system for space cooling in buildings in hot and dry climates. The cooler uses porous ceramic materials as the wet media for water evaporation. Under selected test conditions of airflow dry bulb temperature of up to 45 o C and relative humidity of up to 50%, it was found that the supply air could be cooled to below the wet bulb temperature with a maximum cooling capacity of 280 W/m 2 of the wet ceramic surface area. It was also shown that the overall wet bulb effectiveness is greater than unity. This performance would make the system a potential alternative to conventional mechanical air conditioning systems in hot and dry regions.

The introduction of new housing typologies in emerging cities is rooted in dynamics including infrastructural investments, urban growth rates and new development policies. In accommodating new lifestyles, demand-driven patterns by tenants and property owners are the main factors consolidating development trends in future. This paper explores the relationship between new lifestyle patterns and housing typologies in emerging cities. Within the context of Gulf cities, namely Dubai, Abu Dhabi, Doha and Manama, this paper investigates demographic structures and housing trends where a rapid phase of urban growth has transformed local urbanism. Current social structures were analysed by following a new ‘lifestyle framework’ resulting in the characterization of four main lifestyle trends. This is coupled with the assessment of 240 cases of new residences from the Gulf cities under study. The juxtaposition of both studies offers an outlook relevant to the importance of a transition from supply-driven to demand-driven housing dynamics to accommodate emerging multicultural societies. The paper thus contributes to a better understanding and identification of the social groups that are currently lacking suitable housing.

Evaporative cooling has been considered a low energy consumption process that often is associated with displacement ventilation and passive cooling strategies of buildings. While significant energy savings can be accrued from using evaporative cooling, there are many design challenges to improve the processes of heat and mass transfer and reduce design complexities. This paper seeks to advance the design of evaporative cooling through building and testing a novel regenerative evaporative cooler prototype. It proposes a design that integrates heat pipe and porous ceramic tube modules as an alternative to plate heat exchangers. The paper describes design arrangement of the cooler, a mathematical model and laboratory test results. Under controlled laboratory test conditions, the measured performance indices of wet bulb effectiveness, specific cooling capacity and coefficient of performance (COP) were determined as 0.8, 140 W per m 2 of wet ceramic surface area and 11.43 respectively. Furthermore, experimental results show that under typical ambient conditions commensurate with that prevailing in arid climates, the cooler air supply temperature was as much as 14 o C below that of the ambient air.