Modeling the internal dynamics of energy and mass transfer in an imperfectly mixed ventilated airspace

This paper deals with a modeling approach that combines the classical heat and moisture balance differential equations along with the use of experimental time-series data. This approach provides an ideal form for advanced model-based control system design.

Prediction of the noise installation effect induced by a bend at the inlet of an axial flow fan

This paper presents a comparison of the predicted and measured acoustic system effect induced by a box with a lateral opening at the inlet of an axial flow fan. The objective of this study carried out on an academic configuration, is to develop and validate prediction models for real cases.

Flow Network Model based on Power Balance as Applied to Cross-Ventilation

This paper reviews the flow network model based on power balance as applied to wind-induced cross ventilation in a residential building. The characteristics of wind-induced cross-ventilation with open windows in buildings are different from those of air infiltration through cracks in walls. The features of the velocity and pressure distributions are apparently different. In cross-ventilation, it seems that a kind of stream tube is formed through the building.

Air distribution design based on EN ISO 7730 with the help of a computer program

Klima ADE is a program for fast selection and calculation of air diffusion devices, which isbased on:- Design criteria for the thermal environment are based on EN ISO 7730 (optimaloperative temperature and maximum mean air velocity in occupied zone).

Fault introduction and detection in building HVAC systems

Heating, ventilation and air-conditioning (HVAC) systems play an important role formaintaining a healthy and comfort indoor climate for buildings. Faults in the systems decreasethe performance and lead to higher energy consumption or lower thermal comfort level.Researches of the fault detection and diagnosis (FDD) on the building HVAC systems havebeen presented in recent decades. However, many of them use simulation tools or software tocheck the behaviour under the faulty condition. Few people introduced real faults into the realsystems to get the responses.

A conceptual model to estimate cost effectiveness of the indoor environment improvements

Macroeconomic analyses indicate a high cost to society of a deteriorated indoor climate. Thefew example calculations performed to date indicate that measures taken to improve IEQ arehighly cost-effective when health and productivity benefits are considered. We believe thatcost-benefit analyses of building designs and operations should routinely incorporate healthand productivity impacts.

An interaction model for odour intensity

A laboratory study has been carried out to investigate the exposure response relationshipsbetween perceived air quality (PAQ) and concentration of pollutants. The objective was todevelop an interaction model for odour intensity, which allows predicting the perception of acombination of odours on base of the data for the single pollution sources. In the experiments10-12 persons assessed the PAQ in decipolB directly. Three different materials served aspollution sources.

Optimisation of the indoor thermal comfort in private houses using advanced turbulent models

The simulation has been performed using the CFD package SWIFT. In the first phase, meanflow and thermal comfort parameters of the integral living room of the modern family househave been calculated. In the second phase the effect of turbulence was the subject of interest.Two turbulence models, the k-e and the HTM (Hybrid Turbulence Model), were applied.HTM already showed good results in other application areas, e.g. aerodynamics of cars. Thepresent study demonstrates the new approach in modelling and calculating air conditioning ofthe rooms.

Methods and methodological tools for the elaboration of natural ventilation strategy

The efficacy of a natural ventilation strategy is essentially conditioned by the sizing ofcomponents on which the airflow control depends. The indoor environment conditioning issubmitted to strict regulation. The implementation of the natural ventilation strategy is relatedto the building layout; therefore, the devices sizing is important for the architect. On the basisof the loop equation proposed by James Axley, we developed a simple sizing tool.

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.

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