Tests have been performed on several ceiling air diffusers supplied with low air temperatures (6 to 16°C - 90% humidity) to study water vapour condensation on diffusers surface. Results show that a supply air temperature of 11°C avoids most of condensatio

The risk of contaminant deposition (10 microns particles) on an operating room surgical site is evaluated for different ventilation systems - conventional, laminar, non-aspirating, displacement -, using airflow modeling and particle tracking methodologies. Results show that laminar flows are the most appropriate to avoid particles deposition.

The paper gives an explanation of the phenomenon of attachment of a cold air jet to a ceiling, based on a theoretical analysis. A formula to calculate the distance between the blowing slot and the point where the cold air jet will separate from ceiling is given. The results of calculations using this formula show good agreement with experimental data.

The market evolution of domestic exhaust air heat pumps since 1979 in Sweden is described. Some information is also given about the German market. Technologies of different exhaust air heat pumps systems are shown and results of several monitoring projects in Sweden are summarized : they show for houses built in the 1980's an electricity consumption of 90 to 130 kWh/m2/year (including domestic hot water and household electricity), depending on the thermal characteristics of the building envelope. The energy savings thanks to the exhaust air heat pump are about 30%.

Flow and heat transfer calculations have been operated in a typical office room equipped with a displacement ventilation and a chilled ceiling system. Results show quasi-periodic flow when the values of internal thermal loads are high. They also show lateral oscillations of the plumes above heat sources which create after impact on the cold ceiling recirculating flows in the room.

Suggests that particularly for outdoor thermal comfort assessments in cold conditions, non-steady state models should be applied. This and other new aspects are to be considered in a new internationally standardised Universal Thermal Climate Index (UTCI), at present being developed by the International Society of Biometeorology. Psychological factors also need to be considered, such as diverging thermal expectations indoors and outdoors. States that as a consequence, different approaches are needed to assess indoor or outdoor thermal comfort.

Describes the thermal model available, both simple and complex and outlines capabilities and limitations. States that all of the models have limitations for use in standards, including the accuracy of the physical simulation and the accuracy of the inputs to the model. States that the biggest limitation is probably the accuracy with which comfort perceptions can be related to the physiological variables simulated in the thermal models.

States that existing standards and models are not sufficient to characterise the satisfaction and pleasantness for end-users which is provided by heating or air conditioning. The project described here was devised with the aim of using sensory evaluation techniques in the design of HVAC systems. A dual evaluation is used for sensory evaluation in the food cosmetics, phone and automotive industries, comprising of sensation measurements carried out be a small panel of trained expert assessors and preference studies performed by a large panel of representative consumers.

An analysis was done to look at the differences in the way occupants perceive the office environment. The surveys were done in an office with multinational workers in Japan. The 406 returned questionnaires were grouped by nationality and gender. 26% reported a comfortable working environment. There was a significant neutral temperature difference of 3.1 deg. C between the Japanese female group and the non-Japanese male group. Japanese females reported the highest frequency of sick building syndrome of any of the groups.

The paper compares a long and short term study of naturally ventilated buildings in a city in western Iran. For the hot season the neutral temperatures from the short and long term studies were 28.4 and 26.7 deg. C. For the cold season the short and long term neutral temperatures were 20.8 and 21.2 deg. C. Good agreement is shown between both studies. The results showed how acceptable conditions varied widely, a good relationship between neutral temperature and room temperature and between indoor comfort and outdoor conditions.