Recent Doctoral Dissertations and Theses

Abstract

This thesis presents the form, development and application of generation and optimization concepts as a new CAD model for the design of the dwelling roofs in the warm-humid tropics. Generation is utilized to produce a range of feasible design solutions and optimization is utilized to offer prescriptive quantitative information, the optimum performance achievable in any given climate. The climatic and technological context of the research is presented. The performance standards for dwelling and roof design are reviewed. The process used to define the acceptable limits of ceiling surface temperature based on comfort is described. A method to predict thermal performance of roof is described. This identifies a set of variables which influence the performance of roof. From this theoretical study a new thermal performance index (TPI*) is developed to give a scientific rating to thermal behaviour of the roof system. Computer design aids presently available to the architects for energy efficient dwelling design are critically reviewed in relation to the scope and limitations of the information they provide. The new concepts of generation and optimization are then developed. The CAD model introduces the application of generation method in place of the traditional simulation. Its structure includes, the decomposition of the roof system into elements or components and the definition of their relationships based on topology, geometry and materials. The concept of design template is introduced to encode aesthetic or practical rules about the form of acceptable design solutions. Alternative design solutions are generated by paramterizing the templates using the design preferences of the architect. A material matrix form is introduced to present the alternative solutions. The CAD model includes an optimization procedure which is based on multi-criteria Pareto optimization. The use of this model is illustrated for a number of widely differing roof designs. The resulting thermal performances and optimum solutions are demonstrated for four locations from India and Australia. The value of this form of information in practice, education and research is discussed and possibilities for future development are outlined.