Simulations of indoor air quality and ventilation impacts of demand controlled ventilation in commercial and institutional buildings

Carbon-dioxide (CO2) based demand controlled ventilation (DCV) offers the potential for moreenergy efficient building ventilation compared with constant ventilation rates based on designoccupancy. A number of questions related to CO2 DCV exist regarding energy benefits, optimalcontrol strategies, and indoor air quality impacts for contaminants with source strengths that areindependent of the number of occupants. In order to obtain insight into these issues, a simulationstudy was performed in six commercial and institutional building spaces.

Indoor air quality in retrofitting educational buildings

For historical and demographical reasons, in many European countries, an important part of educational building must be retrofitted. These retrofitting must be carried out in a context of reduction of greenhouse emissions and energy consumption.Among different targets for retrofitting, there are the improvement of indoor environment. In fact, educational buildings are particularly vulnerable to indoor environment problems. Studies have indicated a correlation between the way educational buildings are designed, or retrofitted, and student performance.

Impact of residential natural ventilation and air-tightness techniques on the energy loss and indoor air quality

To better quantify the impact of different window opening models in comparison to ventilation techniques a multizone ventilation model, incorporating the CO2-production of the inhabitants, was developed, using Comis-Transys. The reference model represents a free-standing dwelling in which infiltration is the only source of fresh air. Through a series of simulations natural ventilation systems (standard, user controlled or CO2-based demandcontrolled), air-tightness techniques and/or window opening models (deterministic or stochastic) are added.

Assessment and description of humidity controlled system in french residential buildings

In France, ventilation in new residential buildings must be designed and dimensioned according to the Health regulation (Arrêté du 24 mars 1982) which is basically based on required extract air flow rates. Two points are to be noticed : 1) The extract flo

Energy efficiency and IAQ - Simultaneous improvements in relocatable classrooms.

The aim of that study was to demonstrate the potential to design buildings that can simultaneously improve indoor environmental quality along with a reduction of energy. In that order 4 energy-efficient relocatable classrooms were designed and constructed, each equipped with two different HVAC systems (heat-pump air-conditioning system and an energy-efficient indirect/direct evaporative cooler). Results are presented.

Truth and myth about IAQ

In this one-page paper the author points out the misinformation related to IAQ. He gives a liste of myths and truths about it.

Sick building syndrome : indoor quality and performance implications

Findings about sick building syndrome in Sydney’s offices are presented. The aim is to ascertain whether perceptions of sick building syndrome in offices impact on discrete aspects of workplace performance and management. One hundred offices in the Sydney

Integrated systems demand control technology

The peak electrical demand of office building VAV systems will be reduced by about 1.2 Kw/1000 Ft2 by employing an Integrated Systems Demand Control Technology (ISDCT) sequence to reduce peak intake flow by about 56%.Supply, return, and exhaust fan energy decreases with reduced airflows and pressures; and chiller system energy is saved by reduced cooling coil loads.The ISDCT sequence continuously computes zone contaminant concentrations allowing compliance with reference standards.

Numerical simulation of buildings thermal behaviour and human thermal comfort multi-node models

In this work two numerical models are presented. The first one simulates the buildings thermal response and evaluates the internal air quality, while the second one simulates the human and clothing thermal systems and calculates the thermal comfort level in non-uniform environments. The results obtained by the first model are used as input data in the second one.

Computational and experimental reduced-scale modelling of air conditioned rooms

An improper air distribution within air-conditioned rooms is one of the largest causes of inadequate indoor air quality and thermal comfort. A good knowledge of the phenomena allows for the advance of eventual deficiencies, thus becoming a powerful tool for the optimization of new projects or for the improvement of the operation conditions of the projects already implemented. In this study two methods were applied, one computational and the other experimental, for modelling of non-isothermal turbulent flows in airconditioned rooms. The computational model consists of a numerical

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