Twenty-four college students are asked about their subjective responses to a dynamic thermal environment with non-isothermal and intermittent air movement. The subjects wear an uniform of 0.6 clo and are sedentary. A rotative air jet can cyclically sweep over the subjects with adjustable air velocity. Each experiment lasts 150 minutes and is performed with three stages.
In order to give some guidance for the optimization of shop entrances regarding comfort and energy savings, a project was launched by the City of Zurich. The project covers field investigations in 12 shops with different entrance types, and analytical and numerical investigations (CFD)for complementary results. The emphasis of this work was on the interaction between the situation at the entrance for different technical local solutions with other factors of importance like building ventilation, building tightness and combination with other entrances.
The initial findings of a project initiated in the University of Coimbra and dealing with the conjugated influence of multiple stressors in riding passengers are presented in this paper. A field study in public transportation buses was conducted, having been the subjective responses of the occupants collected and the physical parameters related to the thermal comfort, noise, vibration and air quality acquired. In the questionnaires, the PMV scale was used to evaluate the thermal aspects and, for the other stressors, a five-point scale, from very uncomfortable to very comfortable, was used.
At Hermann-Rietschel-Institute systematic tests of the limits for the ventilation with openable windows are under way. The parameters temperature distribution and air velocity are the most attended values. Window ventilation in office buildings has limits in application. An open window can remove cooling loads out of the room. With one window and a room with a depth of 5 m, the maximum cooling load is about 20 to 30 W/m2. These limits are determined by air velocities within thermal comfort.
This paper presents results on the human response to individually controlled radiant local heating of the body which can be used together with low enthalpy ventilation based on low room air temperature and humidity. Experiments were performed with 18 human subjects to identify the optimum combination and location of local radiant heating panels designed to compensate for cooling of the body at room air temperatures in the range 14-23 °C. The subjects were instructed to change the heating power of the panels and to select the optimum condition that would provide them with thermal comfort.
The general strategy adopted in the development of a computational tool performing the identification of parametric models based on the Residence Times Distribution (Rm) theory is exposed. Two main aspects of the modelling procedure are presented: the structural discrimination of the various solution schemes, and the parameters estimation step. The structural model determination is solved by a stochastic procedure based on a Simulated Annealing algorithm, while the parametric identification is solved by a nonlinear deterministic procedure.
The purpose of the presented investigation is the comparison between measured data of the laminar and turbulent mixed convection and their approximation by wall functions. New wall functions were implemented in a FVM-research-code using unstructured grids, which was developed by the author. Numerical results are compared with a turbulent closed cavity flow.
In order to assess ventilation systems, ventilation and thermal comfort parameters are calculated. Parameters are temperature and ventilation efficiency and PMV I PPD. Two ventilation configurations are set: the supply grille is under the ceiling and tests are performed for 2 exhaust positions. Both are opposite the ceiling: the first one is under the ceiling and the second one is on the floor. In regards with extract position, the ventilation system is better when extract is on the floor. It appears that the air renewal does not influence neither ventilation nor temperature efficiency.