Numerical Studies on Effects of Cavity Width on Smoke Spread in Double-skin Facade

Double-skin façade (DSF) is an environmental friendly architectural feature. However, fire hazard is a concern. A scenario of having a flashover room fire adjacent to the façade was identified. Heat and mass would be trapped in the façade cavity. This paper examines air flow driven out of a flashover room fire to the cavity of a DSF by Computational Fluid Dynamics. The software Fire Dynamics Simulator developed at the Building and Fire Research laboratory, National Institute of Standards and Technology, USA was selected as the simulation tool. Three DSF features labeled as DSF1, DSF2 and DSF3 were considered. Detailed simulations were carried out to understand the fire-induced aerodynamics in a 5-level model DSF1 with a fire room at the third level. Hot gas spreading out to the façade cavity was simulated under two heat release rates of 1 MW and 5 MW. Air cavity depths of 0.5 m, 1 m, 1.5 m and 2 m were considered. Three stages of flame spreading out to a DSF with a wide air cavity depth were identified. Results suggested that wider air cavity depths would be more dangerous, with higher risk of the upper interior glass pane's breaking. To study spreading of heat and mass up the façade cavity as vertical channel flow, two taller DSF façade features DSF2 and DSF3 with differing air cavity depths were simulated. Both features were of height 24 m but of differing fire room height. Vertical temperature profiles with and without the DSF feature were compared. Santrauka Dvigubas fasadas yra ekologiškas architektūrinis sprendimas. Tačiau dvigubas fasadas yra problemiškas gaisrinės saugos požiūriu. Nagrinėjamas scenarijus, kai greta dvigubo fasado esančioje patalpoje įvyksta gaisro pliūpsnis. Dvigubo fasado ertmėje gali būti uždaryti karštis ir masė. Taikomi skaitmeninės skysčių dinamikos metodai nustatyti, kaip iš patalpos, kurįoje įvyksta gaisro pliūpsnis, oras ir degimo produktai išstumiami ī dvigubo fasado ertmę. Modeliuoti naudojama kompiuterinė programa, parengta JAV Nacionaliniame standartų ir technologijos institute. Nagrinėjami trys dvigubų fasadų sprendimai. Atliekamas detalus pirmojo sprendimo fasado modeliavimas siekiant suprasti gaisro lemiamą aerodinamiką penkių aukštų fasade, kai gaisras kyla trečiame aukšte. Modeliuojamas karštu dujų sklidimas iš fasado ertmės viršaus teigiant, kad gaisro išskiriama Siluma yra 1 MW ir 5 MW. Ertmės plotis imamas lygiu 0,5 m, 1,5 m ir 2 m. Nustatomi trys liepsnos sklidimo iš dvigubo fasado etapai. Gauti rezultatai leidžia daryti išvadą, kad platesni fasadai yra pavojingesni, nes didina viršutinių stiklo diskų dužimo tikimybę. Aukštesni antro ir trečio sprendimo fasadai naudoti tirti, kaip karštis ir masė juda vertikalia fasado ertme. Skyrėsi šių fasadų ertmės plotis. Abu fasadai buvo 24 m aukščio, tačiau skyrėsi gaisro patalpos aukštis. Buvo palygintas vertikalusis temperatūros pasiskirstymas dvigubo fasado ertmėje.

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NUMERICAL STUDIES ON SMOKE SPREAD IN THE CAVITY OF A DOUBLE-SKIN FAÇADE

Journal of Civil Engineering and Management ◽

10.3846/13923730.2014.897992 ◽

2015 ◽

Vol 22 (4) ◽

pp. 470-479 ◽

Cited By ~ 4

Author(s):

Jie JI ◽

Yi Fan LI ◽

Wen Xi SHI ◽

Jin Hua SUN

Keyword(s):

Heat Release ◽

Tilt Angle ◽

Key Factors ◽

Release Rates ◽

Turbulent Vortex ◽

High Rise ◽

High Rise Building ◽

Numerical Studies ◽

Smoke Spread ◽

Double Skin

In this paper, influence of two key factors, fire room height and outer pane tilt angle, on smoke spread in the cavity of a double-skin façade (DSF) was studied numerically. The fire room was located adjacent to the DSF on the 2nd, 4th and 6th floors, respectively. The outer pane tilt angle varied at 80°, 90° and 100°. All cases were under two fire heat release rates of 1 MW and 5 MW. Results suggested that fire room height and outer pane tilt angle had significant effects on smoke spread in the cavity. For different fire room heights, there were two markedly different scenarios of smoke spread in the cavity between two vertical panes in a high-rise building. For outer pane tilt angle, the DSF with an inward tilted or vertical outer pane was dangerous for the upper floors due to hot smoke adhering to the upper inner pane. However, the turbulent vortex in the DSF with an outward tilted outer pane prevented hot smoke flowing out from the fire room.

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The impact of sustainability on fire safety

10.26686/wgtn.17004871.v1 ◽

2021 ◽

Author(s):

◽

Mohammad Musa Al-Janabi

Keyword(s):

Fire Safety ◽

Sensitivity Study ◽

Mitigation Measures ◽

Fire Dynamics ◽

Fire Event ◽

Use Of Resources ◽

Smoke Spread ◽

Double Skin ◽

The Impact ◽

Small Models

<p>There is a growing demand for building green buildings that are perceived to have benefits environmentally through promoting recycling, energy efficiency and efficient use of resources. The green movement has also led to innovative technologies that are focused on reducing cost. However, the fire safety industry has concerns with the use of certain technologies that create passages for smoke and fire to spread such as passive ventilation or materials that can burn severely and release large amount of toxins. The benefit of this research is to determine which features are high risk and are commonly used. The aim of this research is to investigate whether sustainable or green features have an influence on fire safety in commercial buildings and determine which feature or features would have the most significant implications for building safety in regards to tenability. A detailed investigation was done on passive ventilation such as double skin facade and the thesis also briefly discusses other green features and their implications. There were two methods used to collect data. The first was a qualitative study done through sending out surveys to fire engineers to rate and rank the most significant features that have negative implications for fire safety in reference to the New Zealand Building Code Fire Safety Section criteria and objectives. Then, a one hour interview was carried out to determine the reason behind the engineers’ choice and their perceptions. The results from the surveys and the interviews were that double skin facade and atrium were ranked the most significant. The surveys established double skin facade has the highest ranking in terms of the worst feature, and the fire engineers reinforced that double skin facade needs to be studied as there is not enough research that have gone into this feature. While atrium issues are known and mitigation measures are well developed. A subsequent analysis for only double skin facade is conducted using Fire Dynamics Simulator (FDS) because little literature is found in regards to fire safety and double skin facade. FDS was used to simulate 14 small models and 2 large models for the best and worst scenarios of DSF. Each of the 14 models, one to three parameters are changed as part of the sensitivity study to determine which parameter have the most and least effect on fire safety in term of Carbon Monoxide (CO) and visibility. The issues the engineers raised and the mitigation measures were modelled, because the engineers had stated their opinions not facts. The output results from FDS illustrated that it is essential that the system shuts off in a fire event to prevent smoke spread to upper floors, which is the same mitigation measure that were emphasised at the interviews.</p>

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Research Review of Impact of Double Skin Facade's Structural Factors on Cavity Heat Transfer

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1030-1032.588 ◽

2014 ◽

Vol 1030-1032 ◽

pp. 588-593

Author(s):

Zhi Yong Wang ◽

Tian Yu Zhang ◽

Chang Rong Liu ◽

Shun Fu Yang ◽

Na Cui

Keyword(s):

Heat Transfer ◽

Research Review ◽

Structural Factors ◽

Transfer Property ◽

Multiple Factors ◽

Heat Transfer Property ◽

Performance Of Heat Transfer ◽

Ventilation Pattern ◽

Double Skin ◽

Cavity Width

The heat transfer property of double skin façade’s façade was analyzed and summarized from the façade’s ventilation pattern, shading mode, cavity width, cavity height, vent openings, the glass optical property and its sequence and convection methods. It showed that the analysis of double skin facade should employ various research methods on the basis of dynamic analysis and comprehensively take multiple factors into consideration on the grounds of actual situation for which may have effects on the heat transfer property of curtains. As a result, more double skin façade with a higher performance of heat transfer can be invented.

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Experimental and numerical studies on the thermal performance of ventilated BIPV curtain walls

Indoor and Built Environment ◽

10.1177/1420326x15611194 ◽

2015 ◽

Vol 26 (9) ◽

pp. 1243-1256 ◽

Cited By ~ 7

Author(s):

Chi-ming Lai ◽

Shuichi Hokoi

Keyword(s):

Thermal Performance ◽

Flow Mechanism ◽

Pv System ◽

Cfd Simulations ◽

Buoyant Force ◽

System A ◽

Numerical Studies ◽

Building Integrated Photovoltaic ◽

Double Skin ◽

Computational Fluid Dynamics Cfd

In this study, we integrated a photovoltaic (PV) system, a double-skin structure and a thermal flow mechanism to design ventilated building-integrated photovoltaic (BIPV) curtain walls that can autogenously control an environment using buoyant force. Full-scale experiments and computational fluid dynamics (CFD) simulations were conducted to investigate the flow pattern characteristics for the channel airflow and the thermal performance of the ventilated BIPV curtain walls under various heating conditions, wall thicknesses and types of openings. Channel flows for different channel widths under the same wall heating exhibited different flow patterns and therefore variations in thermal performance. The developed ventilated BIPV curtain walls effectively removed their solar heat gain while maintaining adequate wall thermal performance.

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Numerical Studies on Smoke Spread in Urban Underground Tunnel with Horizontal Junctions

Procedia Engineering ◽

10.1016/j.proeng.2014.04.063 ◽

2014 ◽

Vol 71 ◽

pp. 441-445

Author(s):

Jun-mei Li ◽

Xiao Feng ◽

Yan-feng Li ◽

Peng Xu ◽

Chen-chen Yin ◽

...

Keyword(s):

Underground Tunnel ◽

Numerical Studies ◽

Smoke Spread

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Spread of smoke and heat along narrow air cavity in double-skin façade fires

Thermal Science ◽

10.2298/tsci110918094c ◽

2014 ◽

Vol 18 (suppl.2) ◽

pp. 405-416 ◽

Cited By ~ 3

Author(s):

Lun Chow

Keyword(s):

Air Temperature ◽

Vertical Channel ◽

Cavity Depth ◽

Glass Pane ◽

Air Cavity ◽

One Dimensional ◽

Hot Gas ◽

Heat Transfer Theory ◽

Smoke Spread ◽

Double Skin

A scenario on double-skin fa?ade fire was identified earlier for hazard assessment. A flashover room fire occurred next to the fa?ade, broke the interior glass pane and spread to the fa?ade cavity. As observed in experiments, hot gas moved up as a vertical channel flow for narrow fa?ade cavity. Heat and smoke spread along the narrow air cavity of a double-skin fa?ade will be studied in this paper. A simple mathematical model is developed from basic heat transfer theory for studying the vertical air temperature profiles of the hot gas flowing along the cavity. Assuming one-dimensional flow for hot gas moving up the fa?ade cavity, conservation equations on mass and enthalpy were solved. Experimental results on two double-skin fa?ade rigs of height 6 m and 15 m with narrow cavity depth were used to justify the results. A total of 11 tests were carried out. Correlation expressions between cavity air temperature and the height above ceiling of the fire room were derived.

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Experimental and numerical studies of short concrete-filled double skin composite tube columns under axially compressive loads

Journal of Constructional Steel Research ◽

10.1016/j.jcsr.2012.09.014 ◽

2013 ◽

Vol 80 ◽

pp. 23-31 ◽

Cited By ~ 24

Author(s):

Wei-bin Yuan ◽

Jun-jie Yang

Keyword(s):

Composite Tube ◽

Numerical Studies ◽

Compressive Loads ◽

Double Skin

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The impact of sustainability on fire safety

10.26686/wgtn.17004871 ◽

2021 ◽

Author(s):

◽

Mohammad Musa Al-Janabi

Keyword(s):

Fire Safety ◽

Sensitivity Study ◽

Mitigation Measures ◽

Fire Dynamics ◽

Fire Event ◽

Use Of Resources ◽

Smoke Spread ◽

Double Skin ◽

The Impact ◽

Small Models

<p>There is a growing demand for building green buildings that are perceived to have benefits environmentally through promoting recycling, energy efficiency and efficient use of resources. The green movement has also led to innovative technologies that are focused on reducing cost. However, the fire safety industry has concerns with the use of certain technologies that create passages for smoke and fire to spread such as passive ventilation or materials that can burn severely and release large amount of toxins. The benefit of this research is to determine which features are high risk and are commonly used. The aim of this research is to investigate whether sustainable or green features have an influence on fire safety in commercial buildings and determine which feature or features would have the most significant implications for building safety in regards to tenability. A detailed investigation was done on passive ventilation such as double skin facade and the thesis also briefly discusses other green features and their implications. There were two methods used to collect data. The first was a qualitative study done through sending out surveys to fire engineers to rate and rank the most significant features that have negative implications for fire safety in reference to the New Zealand Building Code Fire Safety Section criteria and objectives. Then, a one hour interview was carried out to determine the reason behind the engineers’ choice and their perceptions. The results from the surveys and the interviews were that double skin facade and atrium were ranked the most significant. The surveys established double skin facade has the highest ranking in terms of the worst feature, and the fire engineers reinforced that double skin facade needs to be studied as there is not enough research that have gone into this feature. While atrium issues are known and mitigation measures are well developed. A subsequent analysis for only double skin facade is conducted using Fire Dynamics Simulator (FDS) because little literature is found in regards to fire safety and double skin facade. FDS was used to simulate 14 small models and 2 large models for the best and worst scenarios of DSF. Each of the 14 models, one to three parameters are changed as part of the sensitivity study to determine which parameter have the most and least effect on fire safety in term of Carbon Monoxide (CO) and visibility. The issues the engineers raised and the mitigation measures were modelled, because the engineers had stated their opinions not facts. The output results from FDS illustrated that it is essential that the system shuts off in a fire event to prevent smoke spread to upper floors, which is the same mitigation measure that were emphasised at the interviews.</p>

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Numerical Study of Smoke Spread upon Shaft-box Type Double Skin Facades

Procedia Engineering ◽

10.1016/j.proeng.2017.12.072 ◽

2018 ◽

Vol 211 ◽

pp. 755-761

Author(s):

Rui-qi Wang ◽

Shi-jia He ◽

Huan-ran Yue

Keyword(s):

Numerical Study ◽

Smoke Spread ◽

Double Skin ◽

Double Skin Facades

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