Abstract This article presents the study of a ventilation solution using cross-flow fans for the crew quarters (CQ) aboard the International Space Station. Currently the CQ uses two axial fans for ventilation, which occasionally generate insufficient flow rate or acoustic issues. A ventilation circuit using two cross-flow fans was designed, its acoustic performance was measured and the flow was investigated

Abstract A three-dimensional model of an enclosed air-conditioned space was established. Numerical simulation was conducted for the temperature distribution in the enclosed space with the air conditioner turned on using computational fluid dynamics, and the movement track of aerosol droplets exhaled by a patient in the enclosed space was traced using the discrete phase model based on the Eulerian–Lagrangian

Abstract Ductwork airtightness test protocols implicitly assume that the pressure across the leaks is identical for all leaks. In fact, the pressure difference at the leaks decreases in absolute value as the distance from the moving air increases, due to friction and dynamic losses. This paper aims to quantify the impact of these pressure losses on airtightness test results, and thereby the measurement

Abstract An analytical model has been developed for simulating the semi-transparent photovoltaic double-skin façade (STPV-DSF) system to assess its overall performance. The STPV-DSF integrated building can generate electricity, provide daylight illuminance in its indoor area and lowers the energy demand of a building. During the building design phase, complex simulations are required to estimate the

Abstract Today, the fan pressurization method is the most frequently used method to evaluate a building's airtightness. However, the localization and quantification of leaks remain difficult. In this paper, an acoustic method is introduced to estimate the leakage size of single leaks. Acoustic and airflow measurements were conducted and compared in laboratory tests within the same boundary conditions

Abstract The intelligentization of mine ventilation is the inevitable development trend of ventilation system. Rapid, precise, and on-demand (RPOD) adjustment of air volume is one of the main problems that need to be solved in mine intelligent ventilation. In order to realize RPOD adjustment of air volume, the concepts of target branch, active branch and passive branch were elaborated and an algorithm

Abstract Green buildings and sustainable designs require architectural designers to go beyond the basic building codes to improve overall building energy performance, optimize building ventilation, minimize life-cycle environmental impacts and make comfortable inside living environments. This paper briefly introduces the green design of the Lituo farmers market. Improving air quality inside of the

Abstract Based on a case study of the undersea metro interval tunnel, this study proposes a model to evaluate the Ventilation and Smoke Exhaust System (VSES). In the VSES experiments, data of fan frequencies, powers, velocities, and static pressures in carriageways are collected, under the TPTE (Two Pressing-in fans + Two Extracted-out fans), the TPOEL (Two Pressing-in fans + One Extraction fan on

Abstract This article discusses the design of unidirectional airflow systems used to ventilate operating theatres and provide low concentrations of airborne micro-organisms during surgical operations. Also described are tests that can be used to confirm that unidirectional airflow systems are well designed and perform correctly when installed and during their lifetime. Reasons are given for the failure

Abstract The main aim of this study is to predict the temperature characteristics in large-span manufacture area of clean room using the Computational Fluid Dynamics (CFD). The CFD model was established based on a large semiconductor plant and verified by measured data. Then, the effects of these factors including fan filter unit (FFU) configuration, building envelope and fresh air system on temperature

Abstract The building airtightness is essential to achieve a high energy performance. In most countries however, it is not mandatory to measure the airtightness. In the Netherlands it is common practice to just take several samples in a housing project. These samples do not give a good indication for all the buildings in a project. It is therefore important to measure the airtightness of all the buildings

Abstract A traditional residence is not only a symbol of historic wisdom, but also represents the development of superior building experience. The weather in regions south of the Yangtze River is wet and hot; therefore, the local people have taken many effective measures to improve their indoor environment, such as the reasonable layout of windows, the effect of double pitch roofs and the effect of

Abstract A new skin of perforated sheets in the cavity of double skin facades (DSF) system is introduced for efficient heat removal from the cavity in hot summer conditions. In this paper, the analytical solution is developed to estimate the thermal performance of the double-skin façade system with and without perforated sheet operating under natural ventilation mode. This analytical model is designed

Abstract In operating rooms with unidirectional air flow a wake is formed below the light. The influence of the geometry on the dimension of the wake and the age of air were investigated by means of validated numerical simulations as well as experimental measurements. The vertical dimension of the wake caused by the circular surgical light was 1.08 m in height. With an air-permeable shape, it could

Abstract With the modernization of urban development, land resources are becoming increasingly scarce. A new type of building model comprising an underground depot and a superstructure has been constructed. To study the hybrid ventilation (HV) in interlayer of the underground depot with a superstructure under monorail line section fire, full-scale numerical simulation and reduced-scale (1:50) experiment

Abstract Due to experimental data insufficiency for results validation realized by Computation Fluid Dynamics method (CFD), we are proposed new numerical simulations to determined concentration distribution of fine particles in indoor air for transient regime. The ANN model approach of multi-layer perceptron type with three layers is applied successfully. This model requires learning through a database

Abstract With the modernization of urban development, land resources are becoming increasingly scarce. A new type of building model comprising an underground depot and a superstructure has been constructed. To study the hybrid ventilation (HV) in interlayer of the underground depot with a superstructure under monorail line section fire, full-scale numerical simulation and reduced-scale (1:50) experiment

Abstract Due to experimental data insufficiency for results validation realized by Computation Fluid Dynamics method (CFD), we are proposed new numerical simulations to determined concentration distribution of fine particles in indoor air for transient regime. The ANN model approach of multi-layer perceptron type with three layers is applied successfully. This model requires learning through a database

Abstract The impinging jet ventilation (IJV) system has been proposed as a new air distribution strategy and is expected to overcome the disadvantages of mixing ventilation (MV) system, which is the most widely used system, and displacement ventilation (DV), which provides better air quality than MV. The aim of this study is to accumulate the fundamental feature of IJV and to propose a simple method

Abstract Few of existing literatures on the airflow distribution of compartments have studied combined applications of radiant heating and air conditioning in winter. Simulation of airflow distribution in 25 T soft sleeper compartments under different heating and ventilation schemes is provided in this paper. Firstly, reliability of the numerical simulation model has been verified by the experimental

Abstract In some countries, test standards have been adopted which measure the effectiveness of smoke exhaust systems in clearing out heat and smoke produced separately. However, because these standards provide no quantitative provisions for dealing with the amount of visual smoke, there is an unclear correlation between the amount of smoke generated and the fire load. This paper applied the homogeneity

Abstract This paper reports on the development of an organic air cleaner (OAC), an interior architectural element that optimises plants’ CO2 absorption in nonventilated air-conditioned rooms. Sansevieria trifasciata, Dracaena sanderiana, Scindapsus aureus and Syngonium podophyllum were explored. Two methods were adopted: the plants’ CO2 uptake was measured, and the results were used for the computer

Abstract In this study, indoor air quality and thermal conditions were studied under laboratory conditions with the heat load that was located symmetrically or asymmetrically in the room. Diffuse ceiling ventilation (DCV) was adopted to provide cooling and outdoor air to the room. CO2 concentration, room air temperature and air speed were measured in the test chamber. This study gives insight of both

In this study, effect of air change rate (air change per hour – ACH) on indoor particle dispersion and deposition in a ventilated room is investigated. A reduced-scale model is designed to conduct experiments. Numerical predictions are performed by using the commercial software ANSYS Fluent 16.0. Four different values of the air change rate (1.73, 2.88, 5.76 and 7.68) and five different values of the

In an indoor environment, many factors may affect the airflow characteristics and thermal comfort. Hence, a lot of research has been carried out in order to investigate the impact of these factors. The purpose of this study is to determine the effect of supply area, with maintaining the same supply airflow rate, on the airflow characteristics and the indoor thermal comfort for a ventilated box prototype

The fire protection design in a large-scale interchange station is always a great challenge. In this paper, a series of numerical simulations were conducted to investigate the performance of emergency ventilation modes for three potential multisource fire scenarios. The parameters that influence passengers’ evacuation were analyzed. The results demonstrated that unreasonable co-operation ventilation

Abstract Even in case ventilation system is operating in optimal fashion, indoor air quality could be varied depending on the indoor contaminant release occasions. Thus, accurate and rapid identification of contaminant source locations in indoor environment is critical for occupants’ health as well as building safety and integrity. This study presented a novel method to locate indoor contaminant source

A novel DCV-system controls the air-change rate for each apartment in multifamily buildings based on two indoor air parameters: 1) the moisture load (supply), and 2) volatile organic compounds. With a central fan, but decentralized control boxes placed outside each apartment, the system controls the air-change rate for each apartment. This paper’s main aim is to determine the potential of this DCV-system

This study deals with the indoor air quality (IAQ) measured and perceived in a demonstration building via a smart sensor. The analysis subject targeted includes the following main air pollutants, v...

Over the last few decades, there is a clear target for reducing energy needs in the building sector. The above objective can be achieved both by renovating the existing building stock and/or by constructing new buildings that will meet the characteristics of zero or nearly zero energy buildings. In order to construct or renovate a building into a zero or almost zero energy building, different passive

An accurate temperature gradient calculation is essential for displacement ventilation (DV) system design since it directly relates to thecalculation of the required supply airflow rate. Inaccurate...

The indoor air quality is important for the well-being of humans, especially in the case of young babies. This research focuses on the air qualityinside a crib with sleeping infants. The effects of...

A demonstration house was previously built and commissioned in Iqaluit, Nunavut, Canada. The purpose of the overall effort is to develop and integrate technologies and evaluate the performance of a...

Addressing the airtightness of the building envelope is key to achieve thermal comfort, good performance of ventilation systems and to avoid excessive energy consumption. Previous studies have estimated an energy impact on infiltration on the heating demand between 2 and 20 kWh/(m·y) in regions with temperate climates. In Spain, this issue has not yet been addressed in depth. This study aims to assess

Multiple authors stated that, when performing fan pressurization test, Ordinary Least Square (OLS) method should not be used as a regression technique anymore. However, alternative methods require first to quantify components of uncertainty in pressure and air flow rate measurements. This work aims at quantifying the uncertainty in zeroflow pressure approximation, which is mainly due to short-term

Guaranteeing high indoor air quality and high degree of usersatisfaction at the same time is one of the challenges when improving the energy efficiency, namely the energy consumption, of a building...

This study aims to experimentally evaluate the influence of the combination of a supply only ventilation, called here positive input ventilation, and innovative active air vents on the Indoor Air Q...

With increasing building airtightness, the design of an adequate ventilation system gains importance. The first generation of ventilation systems, based on continuous supply of the nominal airflow ...

Buildings typically are expected to provide their inhabitants with the opportunity to influence the indoor environment using various control devices. These include, for example, windows, luminaires...

Ventilation is critical in interpreting indoor air quality (IAQ), yet most IAQ assessments do not report ventilation adequately. Most ventilation assessments use tracer gas tests (TGT) to measure t...

The present paper describes the design improvement of a single-room ventilation unit. This ventilation system presents many advantages, however, several drawbacks exist. The first one is the acoust...

Vertical shafts are common structures in buildings, which accelerate smoke spread in fires due to stack effect. In this study, fire smoke movement and distribution in a ventilation shaft were studi...

Air conditioning engineers design the inlet or outlet position of a fan coil unit (FCU) system according to thermal comfort and cost. However, the effect of the position on fire growth has not been...

This paper reports the results of an interview survey conducted among different stakeholders involved in design, installation and operation of residential ventilation in seven European countries. I...

In this study, smoke evacuation in two kinds of subway station platform models, namely: an island platform station and a two side platforms station is simulated in a three-dimensional configuration...

AbstractWith the wide application of electronic surgical equipment, the generation of surgical smoke is inevitable. Surgical smoke will not only obstruct the operator's visibility, but also release...

AbstractThis paper proposes an original and sustainable design for a Hybrid solar Air Conditioning-Ventilation-Humidification-Dehumidification (HDH) desalination system. The proposed design permits...

AbstractIn this paper the FDS 6 code ability to simulate the airflows generated by jet fans in a real road tunnel is studied. A transient model of the 898 m long bi-directional highway Polana tunne...

Abstract For the interchange tunnel fire, the structural features of bifurcation and convergence will make the smoke movement characteristics different from the traditional single tube tunnel fire. This paper carried out numerical simulations by ANSYS Fluent to study the smoke movement characteristics in large scale interchange tunnel fire. Different heat release rates, ventilation velocities and bifurcation

To study heat and mass transfers inside nuclear facilities equipped with ventilation systems, a methodology was developed to carry out reduced-scale experiments for studying flows induced by therma...

Abstract This study proposed a hybrid ventilation mode for underground subway depot with superstructures and described the construction of a calculation model for estimating the smoke-exhaust efficiency of ventilation systems in such buildings. The hybrid ventilation system consisted of natural ventilation, a flow deflector, and mechanical fans. The smoke-layer height, smoke temperature, gas-flow routes

Abstract The Grid Convergence Index () method requires at least three systematic mesh refinements, each requiring the numerical solution to be in the asymptotic range. When the observed order of accuracy differs from the formal order of accuracy, a lack of numerical precision exists which may result in erroneous conclusions. The aim of the work in this paper is to evaluate the effect the mesh resolution

Abstract In this paper, the impact of window parameters (shape, design, sizes, position and orientation) on the building thermal comfort (temperature, relative humidity and discomfort period), energy consumption (lighting loads, heating and cooling loads and total energy consumption) and cost, and environment effect (CO2 emissions) is analysed under hot semi-arid climate conditions. This study considers

Abstract The present study provides an analysis of existing literature encompassing the wind and thermal analysis of football stadia, and how both can be manipulated through the modification of roof geometry. It introduces the potential for cooling strategies to create an internal environment capable of hosting elite-level international football in a hot climate. The motivation for the study stems

Abstract Noise from domestic ventilation systems is currently a little understood problem in the UK. Other European countries that have a longer history of using mechanical domestic ventilation systems have introduced noise limits for these systems. Without mandatory limits for noise in UK, noise is not a factor that is often considered during the design. However, noise can be a significant constraint

Abstract In the Framework of the IEA EBC Annex68 Subtask 1 working subject, we aimed at defining an indoor air quality index for residential buildings based on long- and short-term exposure limit values. This paper compares 8 indoor air quality indices (IEI, LHVP, CLIM2000, BILGA, GAPI, IEI Taiwan, QUAD-BBC and DALY) by using the French IAQ Observatory database that includes pollutant concentration

Abstract In this paper, the capability of Froude scaling modeling to replicate the fire dynamics in full-scale Murcia Atrium Fires tests equipped with natural and transient forced ventilation was investigated experimentally and numerically by using a 2:27 physical Scale Down Model (SDM) of the full-scale Atrium and CFX-Ansys16.2, respectively. Five SDM experiments were conducted using different heptane

Abstract Sheds roof is a natural ventilation strategy that presents roof openings working as air collectors or extractors. A detailed review of the literature indicates a lack of research analyzing the impact of different sheds roof shapes and roof configurations on natural ventilation potential. This paper aim is to evaluate the impact of changes in distance and alignment between windcatcher and leeward

Abstract Natural ventilation is the most energy-efficient method by which to passively cool a building, reducing the energy consumption, and improving the thermal comfort and indoor air quality. However, designing buildings using cross-ventilation is far more complicated than mere mechanical design due to the indoor and outdoor parameters in addition to the building configurations. The authors have

Abstract One of important parameters of a room microclimate is carbon dioxide level that could be predicted using models presented in literature. In buildings with high heat gains from people, like classrooms, conference rooms or gyms, during estimation of the CO2 concentration it is strongly recommended to take into account changes of indoor air temperature. The article presents a mathematical model