A special garment was developed to measure heat transfer coefficients (convective and radiative) of the clothed human body. It was tested on male subjects operating seated office work in a environmental room. The measured convective and radiative heat transfer coefficients are in good agreement with the PMV model and a number of previous publications.
Monitoring of temperature and relative humidity was carried out in an air-conditioned office building during the heating season. In addition, occupants filled in health and comfort questionnaire. Without informing the occupants, humidity was reduced in an experimental area compared to the control area. As this reduction was not so great (2% relative humidity), the differences of occupants perception between areas are not significant. A slight reduction of building related symptoms was observed at higher humidity.
A method based on both measurements and questionnaire has been developed to investigate comfort in office buildings. The measurements apparatus records temperature, humidity, noise, light, odours and occupant's perceived comfort. The questionnaire contains information about indoor climate and working environment. Results are given and analysed for 60 offices in France.
The impact on thermal comfort of the way of introducing replacement air (to replace air being exhausted by the hood) in a kitchen was analysed using mathematical models and laboratory experiments with a tyhermal mannequin. Results allow to rank systems for replacement air introduction from the most to the least tolerable : displacement ventilation, mixing ventilation with ceiling air diffusers, front-face discharge and backdrop plenum.
The aim of this study is to investigate an optimal air-conditioning adjustment for an indoor space where people come in and out. The authors conducted the experiments by measuring the physiological and psychological responses of subjects who walked outdoors and then entered a chamber. Psychological responses to summer climate were grouped within three categories of: "cool" - "comfortable," "hot" - "uncomfortable," and "cold" - "uncomfortable." These responses are related with subjects perspiration.
This paper proposes a new personal air-conditioning system, which modifies a common partition used in offices to a partition-type fan-coil unit (PFCU) with inlets and outlets on its surfaces. Chilled water is supplied as the cooling energy, and is delivered to the partitions by pipelines incorporated into the structure. Hence, conventional air conditioning systems using ceiling-based air diffusers for open-plan offices may be dispatched into several small individual systems controlled by the occupants.
This paper proposes a new mode of ventilation for indoor airflow. Computational results show that with properly designed supplied air velocity and volume, locations of diffusers and exhausts, the proposed system should be able to maintain better thermal comfort with a smaller temperature difference between the head and foot level, and possibly lower energy consumption, if compared with conventional systems. It looks promising that better indoor air quality (IAQ) in the breathing zone could also be achieved but that further work is needed to determine if IAQ benefits are significant.
CFD calculations were used to compare temperature and air velocities in an environmental chamber equipped either with a conventional comfort overhead air supply system or with an underfloor supply system. Results show the advantages of underfloor system to provide adequate temperature, velocities and turbulence in the seated zone.
For a long time PPD index defined in international ISO7730 standard has been a practical tool for evaluation of measured thermal comfort conditions in existing buildings. However, its usage has not yet been realized in design phase. One of the reasons is that there has not been any practical tool available to estimate average velocity conditions within the occupied zone. A kinetic energy model for calculation of the average room velocity has been presented in earlier paper. Current paper reports additional verification results of the kinetic energy model with different types of diffusers.
The interferometric modeling of temperature fields allows to visualize clearly the distribution of temperatures in typical centres of ventilated and warm air heated spaces and spaces heated using radiators and walls. For the visualization the Mach-Zehnder interferometer is applied and the research is realized on diminished models by means of the similarity theory application.
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