In this paper, the authors are proposing a concept of a radiant ceiling panel HVAC system integrated with ice storage system to cope with the following requirements : load leveling, energy saving, cost saving and thermal comfort. Series of measurements were carried out on six model office fixtures displayed in a room equipped with that concept of radiant ceiling panel.That system provided a good thermal environment which tallied with the Ashrae et ISO recommandations.The authors plan to introduce this system into real buildings.
This paper deals with the use of an Air Curtain Device in a typical HVAC application where there is a need to provide aerodynamic sealing between a comfortable human enclosure and a warmer neighbour space.Three different complementary experiments were used in this work : tracer gas method (N2O), Flow field mapping and Infrared thermo-graphic visualizations.The used experimental methods revealed adequate and complementary to understand the flow topology of the studied case
Emissions due to chicken farming should be minimised because they increase the greenhouse effect on the one hand and odours lead to annoyance. This paper sums up the investigations conducted in various chicken houses to analyse the effect of drying the chicken manure. The emissions streams were measured in different sites with tracer gas (SF6 or Krypton 85). Thanks to suitable ventilation systems the manure can be dried and thus ammonia and odour emissions streams can be purposefully reduced.
Concerning pollution in Hong Kong, the situation is particularly serious in public transfer locations such as public taxi transfer interchanges. Those locations are normally built at ground level under large building complexes, and poorly ventilated. The exhaust gas from vehicles are trapped and the air within those locations is smoky, filthy, and harmful for the passengers. This paper deals with a study on pollutant dispersion and distribution inside that type of sites at off-peak and peak hours. Measurement and analysis of field data are presented.
The second part of the paper deals with the measurements of the indoor thermal environment and the ventilation performance of a commercial kitchen.Measurements were made with a tracer gas (SF6) which is non-toxic and odorless.A smoke machine (ROSCO) was placed on the floor of the middle of the kitchen while operating the ventilated ceiling system. Air inlets near the floor or at the lower parts of the walls brought fresh air in the lower part of the kitchen and pushed the smoke upward.The results almost agreed with the results of the previous numerical simulation ( in part 1).
One way to prevent cold air from entering through the doorway into a building is to use an air curtain. It is a stream of air blown across the doorway that acts as a thermal barrier.
The first part of this paper deals with the performance of a ventilated ceiling system. Field measurements were made in a kitchen of a dietitics school in Kyoto practising mass cooking. The kitchen was half equipped with air canopy hoods to compare with the ventilated ceiling system.
A numerical simulation was conducted with CFD in order to understand the trends of the indoor thermal environment of the kitchen.
This paper aims at showing the difference between the two approaches used to evaluate the capture efficiency of a local ventilation system : an experimental research using the tracer gas method ( CO2) and the numerical modelling using CFD code ( STAR-CD). Comparison between the two methods show that the CFD modelling can provide results in good agreement with the experiment.
An innovative thermal comfort meter has been developed. It can simulate the human body evaporative losses. The sensor has been calibrated in a climatic chamber with different air temperature, velocity and humidity.
Three methods : step-up velocity change, step-down velocity change, and the cut-off frequency method were tested for the dynamic response of two low velocity thermal anemometers.This paper had the objective to identify whether those methods recommended in the standards and guidelines always succeed in determining accurately the frequency response curves and the time constant of low velocities anemometers.