The indoor air quality of an actual variable air volume (VA V) heating, ventilation and air conditioning (HV AC) system in a building on the campus of the University of Missouri, Rolla has been analyzed, modified, and monitored. Components measured include temperature, relative humidity, C02, volatile organic matter (VOM), particulates, outside air flow rate, and building pressure. In addition to these parameters, the building is studied in normal operation, and for operation when the economizer damper was controlled to maintain minimum outside air.

At present, numerical simulation of room airflows is mainly conducted by either the Computational-Fluid-Dynamics (CFD) method or various zonal/network models. The CFD approach needs a large capacity of computer and a skillful expert. The results obtained with zonal/network models have great uncertainties. This paper proposes a new simplified method to simulate three-dimensional distributions of air velocity, temperature, and contan-finant concentrations in rooms. The method assumes turbulent viscosity to be a function of length-scale and local mean velocity.

This paper reports the analysis of the thermal performance of building envelopes of high-rise commercial buildings in the subtropical climate and their interactions with cooling system. Building constructions of commercial buildings in Hong Kong have been investigated and categorized. Their thermal performance and the resulting chiller load is studied with the building energy simulation tool DOE-2. lD. The characteristics of subtropical climate, coupled to high internal gains of commercial buildings, are discussed.

The detailed dynamic simulation of coupled units in HVAC-systems and buildings is gaining increasing importance as strong tool in HVAC-engiiieering and operation. This investigation deals with the basics in the development of an universally applicable dynamic simulator. General fundamentals are formulated some moduls are outlined. Shnulation of a heated 4-room-residence, a solar system. and a storage tank as applications demonstrate the mode of functioning and the potential of the simulator.

The flow-pressure characteristics of the AHU/VAV air-conditioning system in an open-plan office building is assessed by site experiments under various conditions. The effects of VAV supply pressure setting, return fan pressure setting and damper operation on energy consumption, fresh air intake and ex-infiltration flow rate are evaluated analytically on the basis of the VA V/ A.HU system and component characteristics.

The draft of the European prestandard 17 52, entitled "Ventilation for buildings – Design criteria for the indoor environment" is intended to be a flexible tool for assisting the designer in providing a proper indoor environment for people in ventilated buildings. It specifies how the quality of the indoor environment, comprising the thermal environment, the air quality and the acoustic environment can be expressed.

Dynamic simulation of a seawater-cooled chilling system is performed by using the dynamic models of centrifugal chillers, heat exchangers, seawater and chilled water networks, cooling coil, actuator, sensor, variable-speed pump and DDC controller ofBEMS. The on-line control strategies for the central chilling system are tested and evaluated by using them to control the living chilling system under different AHU dynamic loads in four seasons.