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.
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.
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 Mechanical supply only (MSO) ventilationsystem has many advantages, such as good airdistribution, easy pre-heating of cold fresh airsupply and prevention of chemical aerosolsintake through wall cavity. However, thissystem has not been used for dwellings becauseof the risk of the condensation in the wall.
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.
As the technology in building materialsadvances, the room air pollution caused bychemical compounds, and also by preservativesand insecticides for termite control, has becomea serious problem. With Regard to the airconvection in the house to contribute to themovement of the contaminants, there is stackeffect, wind presssure, and mechnicalventilation as the driving forces for airmovement, that is also much affected by the airtightness and ventilation path of the house.
This paper deals with pressurization usingHVAC systems on each floor as acountermeasure against stack effect generated inthe winter in high-rise office buildings that donot use revolving doors at the entrance. Awhole-building pressurization system isinstalled in a 23-story building located in Tokyoin order to prevent various problems caused bythe stack effect, e.g.
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.
Login