Fluid dynamic performances of traditional and alternative jet fans in tunnel longitudinal ventilation systems

Betta, Vittorio; Cascetta, Furio; Musto, Marilena; Rotondo, Giuseppe

doi:10.1016/j.tust.2010.02.006

Cited by 60 publications

(24 citation statements)

References 10 publications

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“…There are two possible solutions for installing ventilation systems in the car park: a) traditional duct system (with 50% of the total exhaust volume taken near the floor and 50% under the roof of the garage), b) Jet fan system. According to Polish regulations, both ventilation systems may be used and generally the price decides which of them is chosen [7,13]. The experiments have shown that in the situation of LPG release, the effectiveness of the traditional duct system can be much lower than from the jet fan system.…”

Section: Ventilation Effectiveness Analysesmentioning

confidence: 99%

“…In this case, in any opening in the car park construction there also exists atmospheric conditions, where especially wind influence is very significant [12]. Jet fan systems are often applied to support ventilation process in car parks [13]. The jet fans are installed under the ceiling of the enclosure to generate high velocity of air flow.…”

Section: Introductionmentioning

confidence: 99%

“…Jet fans are often used in situations where large volumes of air need to be transported with high velocity [13]. However, jet fans were previously used only for tunnels, and premature use in the garages, prior to thorough adaptation to the new destination of car parks [14].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Analyses of LPG Dispersion During Its Accidental Release in Enclosed Car Parks

Brzezińska

Dziubiński

Markowski

2017

Ecological Chemistry and Engineering S

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Despite the fact that LPG (Liquefied Petroleum Gas) is used in a large number of cars, tests have not yet been carried out to ascertain how hazardous can be the release of LPG from the car when parked in enclosed garages. The problem applies to both public and industrial parking areas, especially in Poland, where more than 10% cars are fueled by LPG. The paper describes full scale experiments, which demonstrate conditions that may occur in a garage in the event of accidental LPG release from the car installation. Over the course of the tests, a series of six LPG spillage tests were performed to study emission time and flammable cloud formation depending on the accidental gap diameter. Additionally, to enable the visual observation of the gas dispersion and influence of the ventilation system the experiment was conducted using well visible CO2 gas cloud, produced from dry ice. The experiments have shown that without ventilation LPG can accumulate on the floor of the enclosed garage for a long time, which generates a high explosive hazard. However, good ventilation (especially jet fan systems) can quickly remove hazardous flammable LPG clouds. Moreover, very important for effective LPG detection is the location of detectors closer to the floor than is currently recommended -at a height of 30 cm.

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Section: Ventilation Effectiveness Analysesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Analyses of LPG Dispersion During Its Accidental Release in Enclosed Car Parks

Brzezińska

Dziubiński

Markowski

2017

Ecological Chemistry and Engineering S

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“…The numerical results showed a reasonably good agreement with the experimental results. Betta et al (2010) proposed a 'Banana' jet fan and an optimal pitch angle at a tunnel fire ventilation using CFD. A study investigating the effects of the location of jet fans in a tunnel fire has been described by Se et al (2012).…”

Section: Introductionmentioning

confidence: 99%

Numerical study on fire smoke movement and control in curved road tunnels

Wang

Carvel

et al. 2017

Tunnelling and Underground Space Technology

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This study presents numerical results for critical ventilation velocity and smoke movement for fires in different transverse positions in curved tunnels. The highest critical velocity is observed for a fire positioned next to the convex wall in a curved tunnel where the critical velocity is 16% higher than a fire located centrally in the same curved tunnel which has a curvature radius of 600 m. Critical velocity is observed to vary slightly with curvature, being 7% larger in a 400 m radius tunnel compared to a fire in a straight tunnel. This could be attributed to generally lower speed flows near the convex wall in curved tunnels, and this effect diminishes with larger curve radii. As a consequence, higher smoke temperatures at the ceiling are found for fires near the convex wall in curved tunnels, and tunnel ventilation speed has to be increased to prevent the smoke back-layering in curved tunnels. Additionally, three regimes of back-layering length are concluded for the transverse fire locations in this paper. The first is for a fire next to the tunnel wall, where the back-layering length increases slowly as the air speed tends to be lower than the critical velocity, followed by a rapid rise. Secondly, as a fire moving away from the wall, the back-layering length increases at a gentle gradient. The back-layering length is shortest in this circumstance. A fire in the middle lane and a fire in the lane near convex wall are considered as regime 3. The back-layering length evolution is steepest. Here the back-layering length increases significantly as the tunnel curve radius decreases for the same air speed.

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“…The authors compared the jet fans performance in exhausting the vehicle emissions in severe traffic condition from the tunnel, obtaining the best performance of the innovative ventilation system regarding the local concentration of CO near the human breathing zone of the tunnel. Numerical comparisons of performance of these jet fans with and without traffic jam condition for a tiled tunnel were carried out by Betta et al [2] and Musto et al [3,4]. Wang et al [5] investigated on the optimal pitch angle to reduce the drag coefficient for curved tunnels, vehicles space [6] and radius of tunnel curvature value [7].…”

Section: Introductionmentioning

confidence: 99%