air distribution

Manufactured homes, often referred to as HUD-code homes, are continuing to grow in importance as a national housing resource and represented 23% of all new home construction in 1995. In spite of groundbreaking work to characterize the performance of air distribution systems in site-built housing, in new manufactured homes, the subject has been largely ignored. Field data was gathered from 24 typical new HUD-code homes in four regions in the continental United States. This study describes air distribution system losses estimated through an analysis of system and distribution efficiencies.

Energy efficiency was a significant by-condition in the design work of the New Block (23, 700 m²; 255, 100 ft²) of the University Hospital in the city of Linkoping in Sweden. The block is made up of several interconnecting buildings of between two to four floors, and contains the Heart Centre, the Ear Centre and the Clinic for Infectious Diseases. The principal aim of the design work was to decrease the electrical energy end-uses for air distribution, cooling and lighting (electronic ballasts, occupancy sensors).

Thermal distribution systems represent the most promising opportunities for cost-effective energy savings in residential new construction. This paper describes the results of an unusual but on-going collaboration between the building industry, the environmental community, the research community, and the regulators to develop cost-effective, implementable procedures for improved heating, ventilating and air conditioning (HV AC) duct system design, fabrication, and installation

The characteristics of a hybrid air-conditioning system, utilising natural and mechanical 'task' ventilation, are investigated in an office setting. The characteristics of the indoor environment are examined by means of CFD (Computational Fluid Dynamics) simulations under various conditions of incoming outdoor air. The control of the task air conditioning system (VAV system) is included in the calculation through changing the supply air volume to keep the task zones temperature at a target temperature.

The first part of the paper will show some aspects of experimental research on air distribution in ventilated rooms. The study has been carried out to get an understanding of the air movement and the ventilation effectiveness by means of tracer gas measurements. It has been investigated the velocity and the distribution of the concentration in a two-dimensional isothermal flow issue of a linear supply opening. The second part of the paper will describe a proposed zonal model in 9 zones.