The Experts below are selected from a list of 46014 Experts worldwide ranked by ideXlab platform
J P Vantelon - One of the best experts on this subject based on the ideXlab platform.
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experimental and numerical study of the interaction between water mist and fire in an intermediate Test Tunnel
Fire Technology, 2014Co-Authors: Elizabeth Blanchard, P Boulet, Philippe Fromy, S Desanghere, Pierre Carlotti, J P Vantelon, J P GaroAbstract:The paper deals with interaction between water mist and hot gases in a longitudinally ventilated Tunnel. The work aims at understanding the interaction of mist, smoke and ventilation.The study is based on one intermediate Tunnel Test and an extensive use of the computational code Fire Dynamics Simulator (FDS, NIST). The approach consists first of reconstructing the Test with the CFD code by defining the relevant numerical parameters to accurately model the involved water mist system. Then, it consists of handling from the local data the complicated flows generated by the water mist flooding on the one hand and by fire and ventilation on the other hand. The last stage consists in quantifying each mechanism involved in interaction between water mist and hot gases. There are three main results in this study. Firstly, the CFD code prediction is also evaluated in this configuration, with and without water mist. Before the mist system activation, the agreement is satisfactory for gas temperatures and heat flux. After the activation time, the CFD code predicts well the thermal environment and in particular its stratification. Secondly, water mist plays a strong thermal role since in the Test studied, roughly half of the heat released by fire is absorbed by water droplets. Thirdly, heat transfer from gaseous phase to droplets is the main mechanism involved (73%). The remaining heat absorbed by droplets results from Tunnel surface cooling which represents (9%) and radiative attenuation (18%).
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experimental and numerical study of fire in a midscale Test Tunnel
Fire Safety Journal, 2012Co-Authors: Elizabeth Blanchard, P Boulet, S Desanghere, J P Garo, E Cesmat, R Meyrand, J P VantelonAbstract:Abstract An experimental study has been undertaken in a 1/3 scale Tunnel, using a heptane pool fire up to 4 MW. Temperatures, velocities and radiative fluxes have been registered by a set of 200 sensors located upstream and downstream from the fire location, while mass loss rate of fuel has been recorded. Experiments have been carried out for ventilation regimes below and above the critical backlayering velocity. The constituted database also allows a complete description of the fire development and of the flow regime in various conditions. Numerical simulations have been conducted in parallel. Efforts have been done in order to verify the validity of the simulation by comparing with the experimental database. Further use of the numerical model will allow a complete sensitivity study in order to improve our understanding of this kind of fire. One first analysis has for example demonstrated that the energy balance is strongly dependent on the ventilation regime. In fact, around 50% and 67% of the heat released were dissipated through exchanges with the wall in the sub-critical and over-critical regimes.
J P Garo - One of the best experts on this subject based on the ideXlab platform.
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experimental and numerical study of the interaction between water mist and fire in an intermediate Test Tunnel
Fire Technology, 2014Co-Authors: Elizabeth Blanchard, P Boulet, Philippe Fromy, S Desanghere, Pierre Carlotti, J P Vantelon, J P GaroAbstract:The paper deals with interaction between water mist and hot gases in a longitudinally ventilated Tunnel. The work aims at understanding the interaction of mist, smoke and ventilation.The study is based on one intermediate Tunnel Test and an extensive use of the computational code Fire Dynamics Simulator (FDS, NIST). The approach consists first of reconstructing the Test with the CFD code by defining the relevant numerical parameters to accurately model the involved water mist system. Then, it consists of handling from the local data the complicated flows generated by the water mist flooding on the one hand and by fire and ventilation on the other hand. The last stage consists in quantifying each mechanism involved in interaction between water mist and hot gases. There are three main results in this study. Firstly, the CFD code prediction is also evaluated in this configuration, with and without water mist. Before the mist system activation, the agreement is satisfactory for gas temperatures and heat flux. After the activation time, the CFD code predicts well the thermal environment and in particular its stratification. Secondly, water mist plays a strong thermal role since in the Test studied, roughly half of the heat released by fire is absorbed by water droplets. Thirdly, heat transfer from gaseous phase to droplets is the main mechanism involved (73%). The remaining heat absorbed by droplets results from Tunnel surface cooling which represents (9%) and radiative attenuation (18%).
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experimental and numerical study of fire in a midscale Test Tunnel
Fire Safety Journal, 2012Co-Authors: Elizabeth Blanchard, P Boulet, S Desanghere, J P Garo, E Cesmat, R Meyrand, J P VantelonAbstract:Abstract An experimental study has been undertaken in a 1/3 scale Tunnel, using a heptane pool fire up to 4 MW. Temperatures, velocities and radiative fluxes have been registered by a set of 200 sensors located upstream and downstream from the fire location, while mass loss rate of fuel has been recorded. Experiments have been carried out for ventilation regimes below and above the critical backlayering velocity. The constituted database also allows a complete description of the fire development and of the flow regime in various conditions. Numerical simulations have been conducted in parallel. Efforts have been done in order to verify the validity of the simulation by comparing with the experimental database. Further use of the numerical model will allow a complete sensitivity study in order to improve our understanding of this kind of fire. One first analysis has for example demonstrated that the energy balance is strongly dependent on the ventilation regime. In fact, around 50% and 67% of the heat released were dissipated through exchanges with the wall in the sub-critical and over-critical regimes.
Elizabeth Blanchard - One of the best experts on this subject based on the ideXlab platform.
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experimental and numerical study of the interaction between water mist and fire in an intermediate Test Tunnel
Fire Technology, 2014Co-Authors: Elizabeth Blanchard, P Boulet, Philippe Fromy, S Desanghere, Pierre Carlotti, J P Vantelon, J P GaroAbstract:The paper deals with interaction between water mist and hot gases in a longitudinally ventilated Tunnel. The work aims at understanding the interaction of mist, smoke and ventilation.The study is based on one intermediate Tunnel Test and an extensive use of the computational code Fire Dynamics Simulator (FDS, NIST). The approach consists first of reconstructing the Test with the CFD code by defining the relevant numerical parameters to accurately model the involved water mist system. Then, it consists of handling from the local data the complicated flows generated by the water mist flooding on the one hand and by fire and ventilation on the other hand. The last stage consists in quantifying each mechanism involved in interaction between water mist and hot gases. There are three main results in this study. Firstly, the CFD code prediction is also evaluated in this configuration, with and without water mist. Before the mist system activation, the agreement is satisfactory for gas temperatures and heat flux. After the activation time, the CFD code predicts well the thermal environment and in particular its stratification. Secondly, water mist plays a strong thermal role since in the Test studied, roughly half of the heat released by fire is absorbed by water droplets. Thirdly, heat transfer from gaseous phase to droplets is the main mechanism involved (73%). The remaining heat absorbed by droplets results from Tunnel surface cooling which represents (9%) and radiative attenuation (18%).
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experimental and numerical study of fire in a midscale Test Tunnel
Fire Safety Journal, 2012Co-Authors: Elizabeth Blanchard, P Boulet, S Desanghere, J P Garo, E Cesmat, R Meyrand, J P VantelonAbstract:Abstract An experimental study has been undertaken in a 1/3 scale Tunnel, using a heptane pool fire up to 4 MW. Temperatures, velocities and radiative fluxes have been registered by a set of 200 sensors located upstream and downstream from the fire location, while mass loss rate of fuel has been recorded. Experiments have been carried out for ventilation regimes below and above the critical backlayering velocity. The constituted database also allows a complete description of the fire development and of the flow regime in various conditions. Numerical simulations have been conducted in parallel. Efforts have been done in order to verify the validity of the simulation by comparing with the experimental database. Further use of the numerical model will allow a complete sensitivity study in order to improve our understanding of this kind of fire. One first analysis has for example demonstrated that the energy balance is strongly dependent on the ventilation regime. In fact, around 50% and 67% of the heat released were dissipated through exchanges with the wall in the sub-critical and over-critical regimes.
J B Martino - One of the best experts on this subject based on the ideXlab platform.
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observations of brittle failure around a circular Test Tunnel
International Journal of Rock Mechanics and Mining Sciences, 1997Co-Authors: C D Martini, R S Read, J B MartinoAbstract:Abstract In 1987, AECL proposed several experiments for its Underground Research Laboratory. Among these was the Mine-by Experiment, the main focus of which was to investigate the formation and characteristics of the excavation disturbed zone adjacent to an underground opening. The extent and nature of this zone are important concerns for both the operational safety and the sealing of a vault to control the migration of radionuclides. The excavation response phase of the Mine-by Experiment, which involved the excavation, without explosives, of a 46-m-long, 3.5-m-diameter Test Tunnel in brittle unfractured granite, was carried out between January and July 1992. State-of-the-art instrumentation comprising both geomechanical and geophysical instruments was used to monitor the progressive failure process around the circular Tunnel, and the in situ experiment was supplemented by extensive laboratory Tests. This paper provides a detailed record of the brittle failure process that was observed during excavation of the Tunnel.
Mayavanshi Vijay - One of the best experts on this subject based on the ideXlab platform.
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Experimental study of flow through compressor Cascade
'Elsevier BV', 2017Co-Authors: Panchal Satyam, Mayavanshi VijayAbstract:This article is open-access under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/. First published by Elsevier via http://dx.doi.org/10.1016/j.csite.2017.05.002 © 2017.The objective of this research work is to study the behaviour of flow at the inlet, within the blade passage and at the exit of a compressor cascade. For this purpose, a cascade with six numbers of aerofoil blades was designed and constructed. The cascade was fitted on the cascade Test Tunnel. Out of six blades two were instrumented for measuring the pressure distribution on the pressure and suction surface. The blades had a parabolic camber line, with a maximum camber position at 40% of the chord from the leading edge of the blade. The profile of the blade was C4, height of the blade was 160mm, chord length was 80mm, camber angle was 45° and stagger angle was 30°. Similarly, the length of the cascade was 300mm, span was 160mm, pitch was 60mm, the actual chord of the cascade was 80mm, the axial chord of the cascade was 70mm, the stagger angle of the cascade was 30° and the pitch-chord ratio was 0.75. The data was taken and analyzed at −500% of the axial chord before the cascade, −25% of the axial chord before the leading edge, 25%, 50%, 75% and 150% of the axial chord from the leading edge of the blade. The readings were taken from the cascade wall to the mid span position along the pitch wise direction. The angle of incidence was also changed during the experiment and varied from i=−50°, −30°, −10° to 5°
