Prediction and visualisation of wind flow andpollutant dispersion in urban, densely built areasis necessary for city planners and engineers inorder to regulate and monitor successfully thelocal air quality. Wind vortices, low pressurezones and channelling effects may affect theventilation characteristics of street canyonsunder different meteorological conditions. Inthis respect physical and mathematical modelsare employed which are able to provide insightinto passive cooling techniques for buildingslocated in densely built up areas.

In this study, we evaluated the ventilationperformance of an automobile interior with theaim of minimizing the influence of harmfulmaterials emitted from new cars. We measuredthe ventilation performance of a selecteddomestically manufactured passenger car by theconcentration decay method using tracer gas.For a total of four cases of test conditions, wecompared the ventilation volume andconcentration of pollution materials. Undervarious settings for the internal circulation andexternal circulation of the air circulation unit,the automobile is started in the open air.

The paper presents a new concept for a lowpressure drop supply system suited for theventilation of office spaces. Lower pressurelosses for the air distribution allow a downsizingof the fans cutting down the investment costsfor the equipment and the energy consumptionduring operation. Great potential savings inhigh-valued energy (exergy) are possible inlarge buildings where this concept could reducepressure drops by a factor up to ten. This supplysystem consists of decentralized air handlingunits installed near the facade.

The aim of this study is to examine contaminantdistribution in the occupied zone of a room servedby a novel enhanced displacement ventilationsystem which brings cooler air near the floorupward around human body via 4 fans mounted ateach corner of a chair. An office with twoworkstations was simulated in a full-scale testroom. The discharge angle of the flow from thefans was varied to be 0, 30, and 60" from thehorizontal plane. Two breathing thennal manikinswere used to simulate the occ~~pantwsi th oneserved as a polluting manikin and the other one asan exposed manikin.

We are building a particle tracking systemfor the measurement of convective heat transfersand pollutants displacements in full scale rooms.To increase the depth of the zone of interest, thesystem is non stereoscopic and do not use laserlight. The flow is seeded with 3mm-largeneutrally buoyant helium filled soap bubbles.Illumination is provided by white continuouslight. The seeded flow (air) is recorded by 3high-speed digital video cameras located alongthree different planes.

In building design the requirements for energyconsumption for ventilation, heating and coolingand the requirements for increasingly betterindoor climate are two opposing factors.This paper presents the schematic layout andsimulation results of an innovative multifunctionalventilation concept with little energyconsumption and with satisfying indoor climate.The concept is based on using passivemeasures like stack and wind driven ventilation,effective night cooling and low pressureloss heat recovery using two fluid coupledwater-to-air heat exchangers developed at theTechnical University of Den

The hybrid air-conditioning system is consistsof natural ventilation and mechanicalair-conditioning system in this paper. Theairflow characteristics inside office room withdifferent way to introduce the natural ventilationwere analyzed by means of CFD analysis. Theoffice has the same air-conditioning system byUnder Flow Air Distribution (UFAD). Threeways to introduce the natural ventilation wereused in the analyses. Outdoor air is introducedinto office room from Outdoor Air Intake (OAI)on ceiling, outward wall upper window, andfloor.

In this paper we analyze by means ofbuilding simulation the effect of differentparameter combinations on the non-heating andnon-cooling temperatures of a typical airconditionedoffice building.

Buildings take a great share on the total energyconsumption and C02 emissions in Portugal.Poorly thought buildings pollute the urbanspace, and contribute to the increasing buildingssector energy demand. When thinking inretrofitting old buildings, the common thoughtis that huge amounts of money must be spent onit. This paper, presents a case study on a poorlyenergy performing commercial building, wherea hybrid ventilation free-cooling technique isused to demonstrate its potentiality to efficientlydecrease building energy consumption, withoutrequiring huge investments.

In order to generate effective grid for CFDanalysis of wind environment around buildings in urban area, we newly develop non-uniformtype adaptive mesh refinement method(NUAMR). Different from the conventionaluniform type AMR (UAMR), NUAMR won'tsmooth mesh outside a windward stream tube ofa target region. By comparing overallperformance between UAMR and NUAMR, wereveal NUAMR method's advantage as listedbelow: 1) NUAMR method and UAMR methodhave almost same accuracy in wind velocityratio around a high-rise building.