As the thermal sensation of humans depends directly on heat transfer characteristics between the body surface and the surrounding environment, it is very important to clarify the heat transfer characteristics of a human body surface in detail. This paper describes a combined numerical (NOTE I) simulation system of airflow, thermal radiation and moisture transport based on a human thermo-physiological model used to examine the total (sensible + latent) heat transfer characteristics of a body surface. The human body is assumed to be naked (NOTE 2).
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.
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.
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.
The study of the flow in a room cooled by a fan-coil pointed out how the form of air flow and comfort could be influenced by the characteristics of the cold jet blowing out. It is based both on practical experiment and on numerical simulation using CFD code. Combining these methods allowed a large number of configurations to be studied, in association with different conditions for the appliance. Using the results in combination enabled a relation to be established between the problem data, the device characteristics and the comfort conditions obtained.
Thermal comfort i8sues in a commercial kitchen were studied in a laboratory test series. A commercial instrument was used to predict the thermal comfort of the kitchen personnel working near the hot cooking surfaces. The effect of variables like supply air type and personal nozzles were studied using a thermal comfort meter showing PMV and PPD indeces.
The coupling of simulation methods is an interesting way to get improved or new results concerning thermal conditions in ventilated, heated, and air conditioned rooms. Some results are given for an investigation of a room in a low energy house by building simulation including CFO and the simulation of several heating systems. Comparative studies are done in two different ways. The first way serves to get results about different heating systems concerning thermal comfort and energy consumption and the second one to study the influence of the CFO calculation on the results.
In this paper the experiences carried out in a large church of Bologna equipped with a floor radiant panels heating plant are presented. High intensity air flows were measured not compatible with thermal comfort. Experimental data will form the basis for understanding and controlling thermal instabilities in very high halls.
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.
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