A number of different thermal manikins have been applied in literature to experimentallystudy the indoor environment. These manikins differ in size, shape and level of geometriccomplexity ranging from simple box or cylinder shaped thermal manikins to humanlikebreathing thermal manikins. None of the reported studies, however, deals with the influenceof geometry of the thermal manikin.

Split system air-conditioning units are commonly employed in residential buildings inthe tropics due to their convenience in terms of energy conservation, aesthetics,flexibility, acoustic performance and ease of operation. This paper presents ourfindings from a recent study of the IAQ and ventilation characteristics in a masterbed-room of a condominium unit in Singapore, employed with a split system airconditioningunit. The attached bathroom is equipped with an exhaust fan, whoseoperation and its impact on the resulting IAQ and ventilation characteristics was alsostudied.

The performance of a Personalized Ventilation (PV) system with regard to air qualityperceived by people was studied at three room temperature levels: 23, 26 and 29C. Thirtyhuman subjects participated in the experiment. The system supplied both isothermal (23, 26,29C) and non-isothermal (23C) outdoor air from an outlet attached to a moveable arm. Thesubjects were delegated with control of both airflow velocity and its direction. Physicalmeasurements performed with a breathing thermal manikin were used to explain the resultsfrom the human subject experiments.

A number of different thermal manikins have been applied in literature to experimentallystudy the indoor environment. These manikins differ in size, shape and level of geometriccomplexity ranging from simple box or cylinder shaped thermal manikins to humanlikebreathing thermal manikins. None of the reported studies, however, deals with the influenceof geometry of the thermal manikin.

Existing technical recommendations and standards regarding natural ventilation in Portugalestablish one air change rate, ACH, in main rooms (bedrooms and living rooms) and fourACH in service rooms (kitchens and bathrooms).

Currently, a design of the maximum velocity stress in the occupied zone is based on applicationof the jet theory equations or on the data from the manufacturers catalogue. However, thesemethods are based on the idealized test conditions in empty rooms and do not necessarily predictthe conditions existing in realistic rooms with heat sources and sinks. Furthermore, little data isavailable of the distributions inside the occupied zone. A new statistical method for occupiedzone maximum velocity prediction is introduced and verified using experimental data.

The visual evaluation method has been created for a primary method to verify cleanliness ofHVAC system. The results of two simple measuring methods for thickness of dust and debriswere compared to accumulation values measured by vacuum sampling method. The thicknessof dust layer and the dust accumulation results correlated when the dust was homogeneousbut the correlation was poor if the quality of the dust varied. Both the field and laboratorystudies showed that a commercial contact method gave lower microbial counts than the swabmethod with cultivation.

In the present paper, the influence of the initial inclination angle of the jet on the efficiency ofa vertical downward air curtain is analysed. The air curtain device was mounted over anoverture, in the wall between two equal contiguous rooms, with the typical dimensions of adoor.

A combined windcatcher and light pipe (SunCatcher) was installed in the building of theSchool of Construction Management and Engineering in the MSc Seminar Room (2N09).Monitoring of indoor environment in real weather conditions was conducted to evaluate theperformance of windcatchers in the room and to conduct occupant survey. External weatherconditions and internal indoor environment and air quality indicators were recorded. Thetracer gas decay method using SF6 was used to establish the air change rate for variousconditions.

Almost all existing analysis methods for building ventilation airflows, such as the simpleanalytical methods, multi-zone methods and computational fluid dynamics (CFD), give onlyone unique solution for one set of identical input parameters when started with zeroinitialization or zero initial conditions. This can be shown to be incorrect in some situations.Multiple stable solutions are found in some very simple buildings, which indicate that thebuilding airflows are of a nonlinear dynamical system.