Presumption experiment of supply rate fulfilment using tracer gas verification on the cylinder house

The purpose of this study is to estimate the accuracy of the Supply Rate Fulfilment (SRF)value measured by using tracer gas on a test house. The SRF is intended to evaluate quantityindex and is defined as the ratio of the effective supply rate to the substantial required freshair supply rate. The procedures to measure the SRF value with use of tracer gas techniques,which are constant concentration method and constant injection method, were shown. TheSRF values of the each room in the test house were measured.

The influence on ventilation efficiency in typical dwelling with floor-based displacement ventilation

The characteristics of the climate in Taiwan are high temperature and humidity. In order to solvethese basic problems in dwellings, a meteorological station was established in Fulong(northeastern part of Taiwan) to document the detailed microclimatic information of indoor andambient environments during 4 years. According to the hydrodynamics and thermal mechanics,the new ventilation strategy was developed with the thermal mass cooling-down systemconstructed as the porous floor in a full-scale climate chamber.

Distribution of room air contaminant concentrations as a function of ventilation and air cooling: a numerical investigation

The paper deals with a numerical investigation of the influence of ventilation and airconditioning on the distribution of pollutant concentrations in buildings. The model used is acoupled thermal and airflow model where the room is divided into 18 sub-zones.Temperatures and pressures are determined from the mass and energy conservation equationsin each sub-zone, while airflow rates between two adjacent sub-zones are determined from theBernoulli equation.

Relative influence of boundary conditions on the indoor air quality of a displacement ventilated room

In the indoor air quality (IAQ) assessment of ventilated enclosures it is useful to know therelative influence of key boundary conditions on the personal exposure and ventilationeffectiveness, for instance as a source of information on where to allocate the greatest effortin the design phase. CFD is used to predict ventilation effectiveness and personal exposure tocontaminant sources in a displacement ventilated room subject to variation of several keyboundary conditions.

Tracer gas measurement of airflow rates in rooms with several air-handling units

Methods to measure airflow rates using tracer gas in single air handling units are well known.However, in some buildings, in particular in Singapore, rooms are often ventilated with two ormore units. An adapted methodology that should be used to measure not only the airflow ratesprovided by each unit, but also to determine the inter-units airflow rates and the globalventilation efficiency is presented.

A study of demand-controlled ventilation (DCV) and constant air volume (CAV) systems

One of the most common measures of IAQ (indoor air quality) is carbon dioxide, CO2, generated by human respiration, in particular, where the main source of pollutions are occupants. In this report, the occupancy-related pollutants are considered as the main pollutant source. However, other type of sources may also be removed satisfactory when governing the ventilation system for removal of

Use of a sensory irritation potential index to characterize improvement of indoor air quality in French schools by ventilation

After several cases of health problems in French schools, a methodology for health riskassessment related to indoor air quality (IAQ) was required. Based on measuredconcentrations in schools where acute symptoms possibly due to exposure to airborne sensoryirritants were reported, an index quantifying the sensory irritation potential was built andused. This paper focuses on one classroom where the index was successively applied withoutany ventilation system, after the implementation of passive ventilation grids and with amechanically controlled ventilation.

Indoor air quality and airflow distribution as a new factor in surgical operating theatres: a new hypothesis

This paper reviews the previous attempts to evaluate the Indoor Air Quality (IAQ),investigates previously proposed IAQ factors and analyses the evaluation methods of thesefactors. The present work also introduces a new hypothesis of the optimum HVAC airsidesystem design of the surgical operating theatres to achieve the comfort and hygiene levels.The present work is devoted to propose and formulate a new scale capable of adequatelyevaluating the airflow pattern in the surgical operating theatres. The proposed new scale isproposed to cover the local and overall air quality evaluations.

Experimental and numerical VOC concentration field analysis from flooring material in a ventilated room

The aim of this study is to analyse the impact of volatile organic compounds emissions from asolid flooring material on the concentration field in a ventilated room. A field study has beenconducted in the CSTB experimental house MARIA. Measurements were performed in a testroom recently equipped with a flooring material made of pine wood and under controlledventilation conditions. a-Pinene was selected as tracer from flooring VOC emissions. Velocityand temperature fields are measured in different points of the room.

Deflection ventilation - a conceptual introduction

This paper proposes a new mode of ventilation for indoor airflow. It uses a plate or a curvedvane to divert a jet of air directly into the breathing zone. Computational results show that withproperly selected diffuser locations and design air supply velocities, the proposed systemwould be able to maintain better thermal comfort with a smaller temperature differencebetween the head and foot level, and possibly lower energy consumption, when compared withconventional systems.

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