The ordinary displacement ventilation system (DV) needs large installation spaces for large supplydiffusers with lower supply air velocity to avoid the draft discomfort at the foot level, and large supply airvolume to control allowable vertical temperature gradient within the occupied zone. Furthermore, theDV is difficult to heat without other warming means in the winter. The swirling induction type HVACsystem (SWIT) was developed as utilizing a compact air diffuser increasing the induction function bymeans of swirling air jets.
The interaction of flows in rooms ventilated by active chilled beams and its importance for the air distribution and occupants’ thermal comfort is studied in a full-scale room experiments. The impact of the supplied flow rate of primary air (1.5 L/s/m2 an
As a new way of air conditioning, task air conditioning (TAC) system is often used in combine withbackground air conditioning (traditional central air conditioning) system. In this research, the ComputationalFluid Dynamics (CFD) technique is used to analyze the impact on thermal environment of task zone whenthese two air conditioning systems are used together. The purpose is to find the thermal satisfactory workingconditions of the task air conditioning when the temperature of the background air conditioning is set to behigh.
Air conditioning in offices has become current practice in North Western Europe. Main reasons are thehigh internal loads and solar gains. That move away from the heated, naturally ventilated cellularoffice increased comfort complaints.Two cases are presented, confronting enquiry results with measurements. In both, the enquiries gavea number of dissatisfied at the noted mean vote much higher than the standard PMV/PPD curvesuggests. Measurements in turn showed that only in one of the two case complaints could beexpected.
This work examines the applicability of comfort criteria, based on a heat balance model and on anadaptive model, in naturally ventilated classrooms. The adaptive opportunity of students are limitedduring the lesson time, while they are free during the lesson breaks. The field study was conducted byphysical observations, survey questionnaires and behavioral observations. Both field measurementsand subjective surveys were performed at the same time during the regular lesson period.
In this paper, a new experimental method for measuring thermal conductivity and thermal partitioncoefficient for building materials is presented. The uniqueness of this method is that theaforementioned physical properties are measured for the building materials under the same conditionsas in real life. This method is based on monitoring the temperature difference across the sample andthe solution of the transient conduction equation. The proposed method and designed apparatus weretested using some building materials (i.e.
Experiments using human subjects have been conducted to investigate the physiological andpsychological responses to two different heating methods, i.e. floor heating and air conditioner, in ahighly insulated house. This paper describes a study on the effects of the heating methods on skintemperature changes by investigating changes in skin temperature caused by thermal conditions,sexual differences in skin temperature change, the correlation between declared scores and drops inperipheral skin temperature using the experimental results.
University dormitory is a kind of representative building in which central heating is supplied. The rooms are in simple types and the students’ activity schedule is quite steady, which makes dormitory room to be an appropriate place for field survey. This
This paper describes some of the thinking behind the thermal comfort provisions of the new European StandardEN15251 (CEN: 2007) which deals with all aspects on the indoor environment. The paper will present the evidence on which its provisions are based (focusing on thermal comfort) and the advantages they present for those concerned to design buildings which use the minimumof energy.
There are about 16 millions building in Turkey. The total energy consumption of these buildings is approximately 3.48x105 GJ. The energy consumption of the office buildings having HVAC systems can be stated as 150 kWh/m2.year.Turkey is in the warm climate band and the day time outside air temperature in summer (May ~ September) is about 30C. Parallel to the increasing comfort demands, energy consumption also increases. These factors make the necessity for increasing energy efficiency of buildings apparent.
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