Flammable gas cloud build up in a ventilated enclosure

2010 ◽  
Vol 184 (1-3) ◽  
pp. 170-176 ◽  
Author(s):  
M.J. Ivings ◽  
S.E. Gant ◽  
C.J. Saunders ◽  
D.J. Pocock
Keyword(s):  
Flammable Gas ◽  
Gas Cloud ◽  
Flammable Gas Cloud

A New Gas Turbine Enclosure Ventilation Design Criterion

2005 ◽  
Author(s):  
Roger C. Santon ◽  
Matthew J. Ivings ◽  
David K. Pritchard
Keyword(s):  
Gas Turbine ◽  
Design Criterion ◽  
Cfd Modelling ◽  
Safety Criterion ◽  
Flammable Gas ◽  
Computational Fluid Dynamics Cfd ◽  
Acoustic Enclosures ◽  
New Criterion ◽  
Gas Cloud ◽  
Flammable Gas Cloud

Dilution ventilation is a widely used means of protection against the risk of explosion within gas turbine acoustic enclosures arising from the leakage and accumulation of flammable gas and its ignition from the turbine. In ASME 98GT-215 a safety criterion was proposed for the design of ventilation by defining the allowable size of flammable gas cloud as a proportion of the enclosure volume. This criterion was theoretically based, with a significant safety factor. Whilst generally viable, it was found to be difficult to achieve in some cases. A research project, described in ASME GT-2002-30469, was launched to define a criterion more accurately and with known conservatism based on a detailed programme of experimental explosions and Computational Fluid Dynamics (CFD) modelling. The $600k project was largely financed by the gas turbine industry, including suppliers and users, and by CFD contractors. The paper describes the project aims, its scope of work, and includes the main results, the new criterion and conclusions.

On the non-monotonic wind influence on flammable gas cloud from CFD simulations for hazardous area classification

2020 ◽  
Vol 68 ◽  
pp. 104278
Author(s):  
Paloma L. Barros ◽  
Aurélio M. Luiz ◽  
Claudemi A. Nascimento ◽  
Antônio T.P. Neto ◽  
José J.N. Alves
Keyword(s):  
Cfd Simulations ◽  
Hazardous Area ◽  
Flammable Gas ◽  
Wind Influence ◽  
Area Classification ◽  
Gas Cloud ◽  
Flammable Gas Cloud

STUDY OF GAS FUEL LEAKAGE AND EXPLOSION IN THE ENGINE ROOM OF A SMALL LNG-FUELED SHIP

2021 ◽  
Vol 161 (A3) ◽  
Author(s):  
Q G Zheng ◽  
W Q Wu ◽  
M Song
Keyword(s):  
Injury Risk ◽  
Engine Fuel ◽  
Limited Region ◽  
Gas Dispersion ◽  
Engine Room ◽  
Flammable Gas ◽  
Gas Fuel ◽  
Fuel Leakage ◽  
Gas Cloud ◽  
The Given

The engine fuel piping in LNG-fuelled ships’ engine room presents potential gas explosion risks due to possible gas fuel leakage and dispersion. A 3D CFD model with chemical reaction was described, validated and then used to simulate the possible gas dispersion and the consequent explosions in an engine room with regulations commanded ventilations. The results show that, with the given minor leaking of a fuel pipe, no more than 1kg of methane would accumulate in the engine room. The flammable gas clouds only exit in limited region and could lead to explosions with an overpressure about 12 mbar, presenting no injury risk to personnel. With the given major leaking, large region in the engine room would be filled with flammable gas cloud within tens of seconds. The gas cloud might lead to an explosion pressure of about 1 bar or higher, which might result in serious casualties in the engine room.

Study of Gas Fuel Leakage and Explosion in the Engine Room of a Small LNG-Fuelled Ship

2019 ◽  
Vol 161 (A3) ◽  
Keyword(s):  
Injury Risk ◽  
Engine Fuel ◽  
Limited Region ◽  
Gas Dispersion ◽  
Engine Room ◽  
Flammable Gas ◽  
Gas Fuel ◽  
Fuel Leakage ◽  
Gas Cloud ◽  
The Given

The engine fuel piping in LNG-fuelled ships’ engine room presents potential gas explosion risks due to possible gas fuel leakage and dispersion. A 3D CFD model with chemical reaction was described, validated and then used to simulate the possible gas dispersion and the consequent explosions in an engine room with regulations commanded ventilations. The results show that, with the given minor leaking of a fuel pipe, no more than 1kg of methane would accumulate in the engine room. The flammable gas clouds only exit in limited region and could lead to explosions with an overpressure about 12 mbar, presenting no injury risk to personnel. With the given major leaking, large region in the engine room would be filled with flammable gas cloud within tens of seconds. The gas cloud might lead to an explosion pressure of about 1 bar or higher, which might result in serious casualties in the engine room.

scholarly journals Intelligent Mobile Wireless Network for Toxic Gas Cloud Monitoring and Tracking

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3625
Author(s):  
Mateusz Krzysztoń ◽  
Ewa Niewiadomska-Szynkiewicz
Keyword(s):  
Data Exchange ◽  
Mobility Model ◽  
Model Parameters ◽  
Toxic Substances ◽  
Cloud Detection ◽  
Gas Dispersion ◽  
Gas Concentration ◽  
Cloud Monitoring ◽  
Optimal Values ◽  
Gas Cloud

Intelligent wireless networks that comprise self-organizing autonomous vehicles equipped with punctual sensors and radio modules support many hostile and harsh environment monitoring systems. This work’s contribution shows the benefits of applying such networks to estimate clouds’ boundaries created by hazardous toxic substances heavier than air when accidentally released into the atmosphere. The paper addresses issues concerning sensing networks’ design, focussing on a computing scheme for online motion trajectory calculation and data exchange. A three-stage approach that incorporates three algorithms for sensing devices’ displacement calculation in a collaborative network according to the current task, namely exploration and gas cloud detection, boundary detection and estimation, and tracking the evolving cloud, is presented. A network connectivity-maintaining virtual force mobility model is used to calculate subsequent sensor positions, and multi-hop communication is used for data exchange. The main focus is on the efficient tracking of the cloud boundary. The proposed sensing scheme is sensitive to crucial mobility model parameters. The paper presents five procedures for calculating the optimal values of these parameters. In contrast to widely used techniques, the presented approach to gas cloud monitoring does not calculate sensors’ displacements based on exact values of gas concentration and concentration gradients. The sensor readings are reduced to two values: the gas concentration below or greater than the safe value. The utility and efficiency of the presented method were justified through extensive simulations, giving encouraging results. The test cases were carried out on several scenarios with regular and irregular shapes of clouds generated using a widely used box model that describes the heavy gas dispersion in the atmospheric air. The simulation results demonstrate that using only a rough measurement indicating that the threshold concentration value was exceeded can detect and efficiently track a gas cloud boundary. This makes the sensing system less sensitive to the quality of the gas concentration measurement. Thus, it can be easily used to detect real phenomena. Significant results are recommendations on selecting procedures for computing mobility model parameters while tracking clouds with different shapes and determining optimal values of these parameters in convex and nonconvex cloud boundaries.

Sign in / Sign up

Export Citation Format

Share Document