air conditioning

Floor heating is characterized by small horizontal and vertical temperature differences, and might be especially suitable for Japanese homes where it is customary to sit on the floor. This paper compares thermal comfort in homes while floor heating systems and air conditioning systems were in use during winter. Each dwelling had both a floor heating system and an air conditioning system, each used on alternate weeks during the survey period.  Throughout the survey periods residents were asked about their current thermal sensation, thermal preference, overall comfort and foot-comfort.

The paper discusses the concept of an adaptive thermal comfort design methodology and its impact on the selection, design and performance of climate control systems for large public spaces with transient occupancy in hot and humid climates. It outlines the design methodology which is based on providing localised comfort conditions to zones within a building based on its occupancy patterns, activity of occupants and acceptable thermal comfort criteria. The methodology focuses on quantifying the collective impact of space operating parameters on the thermal comfort of its occupants.

This work is based on the RESHYVENT project  in which the effectiveness of hybrid (i.e. combined natural and mechanical ventilation) was measured and investigated in the urban canyon of Athens, Greece – the most important conclusion being that natural ventilation is dominant. It is suggested that the individual reaction to Air Conditioned Buildings should be better investigated, since many people ask for the comfort associated with natural ventilation. 

LBNL - Proceedings of Indoor Air 2002 (9th International Conference on Indoor Air Quality and Climate) - June 30 - July 5, 2002 - Monterey, California - vol 1, pp 521-526, 3 figs, 10 refs","This paper presents a model for particle deposition on fin-and-tube heat exchangers, that takes into account mechanisms such as impaction, diffusion, gravitational settling and turbulence. Models results are presented and analysed. They agree with experimental data.

The term air conditioning not only prescribes comfort temperature and relative humidity, but also the quality of air inside the room. Indoor Air Quality (IAQ) has become a concomitant of air conditioning. The pollutants generated inside the room affect the quality of air inside the room. The major pollutants considered are occupant generated (carbon dioxide - CO2, odour), sulphur dioxide and toluene etc. The monitoring and controlling of all pollutants is cumbersome.

The aim of this paper is to discuss the impact of the relation between varying indoor and outdoor conditions on the ventilation loads of buildings and to provide HVAC designers with the respective information needed for the optimum dimensioning of the system. The total load generated by one litre per second of fresh air brought from the outside environment to the indoor space conditions, called -ventilation load index-, is calculated for the cities of Athens and Thessaloniki, Greece. The same principles can be applied to other locations.

This paper reviews the previous attempts to evaluate the Indoor Air Quality (IAQ), investigatespreviously proposed IAQ factors and analyses the evaluation methods of these factors. The presentwork introduces, also, a new hypothesis of the optimum HVAC airside system design of the surgicaloperating theatres to achieve the comfort and hygiene levels. The present work is devoted to proposeand formulate a new scale capable of adequately evaluating the airflow pattern in the surgicaloperating theatres. The proposed new scale is proposed to cover the local and overall air qualityevaluations.

An automotive part manufacturing plant in Southern Italy, which has just recently been modernized and extended, offers an interesting panorama of innovative cost-effective solutions for ventilating, air-conditioning and process cooling.

The use of electricity in buildings constitutes around 16% of Singapore’s energy demand. To incorporate energy efficiency measures is one of the key mission to ensure that the economy is sustainable. The recently launched building energy efficiency labell

Reported symptoms from 2000 workers in air-conditioned offices and from 500 workers in natural ventilated buildings have been analyzed using univariate and multiple logistic regression models.The conclusion of that study is that buildings with air conditioning have a higher prevalence of work related upper respiratory symptoms than buildings with natural ventilation though located in tropical country with high relative and absolute humidity rates all around the year.