5.0 Mechanical Ventilation & Air Conditional System 5.1 Literature Review
Air-conditioning system has become a requirement for most of the building in the past few decades. Many of our homes and most offices and commercial facilities wuld not be comfortable without year-round control of the indoor environment. Along with rapid development in improving human comfort came the realization that goods could be prodeced better, faster, and more economically in a properly controlled environment. In fact, many goods today could not be produced if the temperature, humidity, and air quality were not controlled within very narrow limits. Present practitioners of the arts and sciences of heating, ventilating, and air-conditioning (HVAC) system design and simulation are challenged as never before. Developments in electronics, controls and computers have furnished the tools allowing HVAC to become a high-technology industry. Good preparation for a study of HVAC system design most certainly includes courses in thermodynamics, fluid mechanics, heat transfer, and system dynamics. The principles of fluid mechanics, especially those dealing with the behaviour of liquirds and gases flowing in pipes and ducts, furnish important tools. The economic tradeoff in the relaionship between flow rate and pressure loss will be intertwined with the thermodynamic and heat transfer concept. HVAC system generally share common basic elements even though they may differ greatly in physical appearance and arrangement. These systems may also differ greatly in the manner in which they are controlled and operated. HVAC systems are categorized according to the manner by which they distributd energy and ventilation air, by how they are controlled, and by their special equipment arangements.
1