The Experts below are selected from a list of 6015 Experts worldwide ranked by ideXlab platform
Francis Bonthoux - One of the best experts on this subject based on the ideXlab platform.
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experimental characterization of a plume of passive contaminant above a thermal source capture efficiency of a fume extraction hood
Annals of Occupational Hygiene, 2009Co-Authors: R Devienne, Jeanraymond Fontaine, Jeremie Kicka, Francis BonthouxAbstract:Industrial Ventilation problems can be linked to the formation of thermal plumes that develop due to natural convection above various heat sources. These plumes, independent of the energy losses and thermal constraints caused, can also be the carrier of polluting products. This article describes an experimental study of the dynamic, thermal, and mass fields that develop from a hot rectangular (0.5 3 1.25 m) horizontal source. The metrology available allows the measurement of not only the local temperatures and velocities but also the concentration of a tracer gas (helium). Mathematical models have been developed enabling representation of the fields concerned; their characterization by isothermal, iso-velocity, or iso-concentration curves; calculation of the flow rate carried by the plume at a given height; calculation of the enthalpy transport; and so on. Moreover, a pollutant capture device has been introduced, and the measurement technique used allows the determination of various efficiencies of practical interest. The ratio of capture flow to free plume flow at a particular height appears to correlate well with the mean efficiencies obtained for distinct source temperatures.
R Devienne - One of the best experts on this subject based on the ideXlab platform.
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experimental characterization and numerical simulation of plumes above thermal sources transport of a passive contaminant
2010 14th International Heat Transfer Conference Volume 7, 2010Co-Authors: R Devienne, Jeanraymond Fontaine, Talel MaalejAbstract:Industrial Ventilation problems are linked with plumes above heat sources. This paper proposes an experimental study of dynamic, thermal and concentration fields that develop from cylindrical complex or rectangular sources. The metrology allows the measurement of local velocities and temperatures but also of the concentration of a tracer gas (helium). The results are compared with the classical analytical formulae, more particularly in the proximal field and also to results issued from simulation.Copyright © 2010 by ASME
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experimental characterization of a plume of passive contaminant above a thermal source capture efficiency of a fume extraction hood
Annals of Occupational Hygiene, 2009Co-Authors: R Devienne, Jeanraymond Fontaine, Jeremie Kicka, Francis BonthouxAbstract:Industrial Ventilation problems can be linked to the formation of thermal plumes that develop due to natural convection above various heat sources. These plumes, independent of the energy losses and thermal constraints caused, can also be the carrier of polluting products. This article describes an experimental study of the dynamic, thermal, and mass fields that develop from a hot rectangular (0.5 3 1.25 m) horizontal source. The metrology available allows the measurement of not only the local temperatures and velocities but also the concentration of a tracer gas (helium). Mathematical models have been developed enabling representation of the fields concerned; their characterization by isothermal, iso-velocity, or iso-concentration curves; calculation of the flow rate carried by the plume at a given height; calculation of the enthalpy transport; and so on. Moreover, a pollutant capture device has been introduced, and the measurement technique used allows the determination of various efficiencies of practical interest. The ratio of capture flow to free plume flow at a particular height appears to correlate well with the mean efficiencies obtained for distinct source temperatures.
Jeanraymond Fontaine - One of the best experts on this subject based on the ideXlab platform.
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experimental characterization and numerical simulation of plumes above thermal sources transport of a passive contaminant
2010 14th International Heat Transfer Conference Volume 7, 2010Co-Authors: R Devienne, Jeanraymond Fontaine, Talel MaalejAbstract:Industrial Ventilation problems are linked with plumes above heat sources. This paper proposes an experimental study of dynamic, thermal and concentration fields that develop from cylindrical complex or rectangular sources. The metrology allows the measurement of local velocities and temperatures but also of the concentration of a tracer gas (helium). The results are compared with the classical analytical formulae, more particularly in the proximal field and also to results issued from simulation.Copyright © 2010 by ASME
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experimental characterization of a plume of passive contaminant above a thermal source capture efficiency of a fume extraction hood
Annals of Occupational Hygiene, 2009Co-Authors: R Devienne, Jeanraymond Fontaine, Jeremie Kicka, Francis BonthouxAbstract:Industrial Ventilation problems can be linked to the formation of thermal plumes that develop due to natural convection above various heat sources. These plumes, independent of the energy losses and thermal constraints caused, can also be the carrier of polluting products. This article describes an experimental study of the dynamic, thermal, and mass fields that develop from a hot rectangular (0.5 3 1.25 m) horizontal source. The metrology available allows the measurement of not only the local temperatures and velocities but also the concentration of a tracer gas (helium). Mathematical models have been developed enabling representation of the fields concerned; their characterization by isothermal, iso-velocity, or iso-concentration curves; calculation of the flow rate carried by the plume at a given height; calculation of the enthalpy transport; and so on. Moreover, a pollutant capture device has been introduced, and the measurement technique used allows the determination of various efficiencies of practical interest. The ratio of capture flow to free plume flow at a particular height appears to correlate well with the mean efficiencies obtained for distinct source temperatures.
Jeremie Kicka - One of the best experts on this subject based on the ideXlab platform.
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experimental characterization of a plume of passive contaminant above a thermal source capture efficiency of a fume extraction hood
Annals of Occupational Hygiene, 2009Co-Authors: R Devienne, Jeanraymond Fontaine, Jeremie Kicka, Francis BonthouxAbstract:Industrial Ventilation problems can be linked to the formation of thermal plumes that develop due to natural convection above various heat sources. These plumes, independent of the energy losses and thermal constraints caused, can also be the carrier of polluting products. This article describes an experimental study of the dynamic, thermal, and mass fields that develop from a hot rectangular (0.5 3 1.25 m) horizontal source. The metrology available allows the measurement of not only the local temperatures and velocities but also the concentration of a tracer gas (helium). Mathematical models have been developed enabling representation of the fields concerned; their characterization by isothermal, iso-velocity, or iso-concentration curves; calculation of the flow rate carried by the plume at a given height; calculation of the enthalpy transport; and so on. Moreover, a pollutant capture device has been introduced, and the measurement technique used allows the determination of various efficiencies of practical interest. The ratio of capture flow to free plume flow at a particular height appears to correlate well with the mean efficiencies obtained for distinct source temperatures.
Yaser Baharfar - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of Tobacco Dust and Designing of Local Exhaust Ventilation (LEV) Systems in a Tobacco Processing Industry Evaluation of Tobacco Dust and Designing of Local Exhaust Ventilation (LEV) Systems in a Tobacco Processing Industry
2012Co-Authors: Mahmoud Mohammadyan, Yaser BaharfarAbstract:This study was carried out to evaluate tobacco dust concentration and also designing a suitable Ventilation system for reduction of tobacco dust concentration in a tobacco processing factory in the north of Iran.Gravimetric method was used to determine the tobacco dust concentrations in the emission sources an also indoor workplace. A local exhaust Ventilation system was designed according to the velocity pressure method recommended by ACGIH. Mean tobacco dust concentrations (ranged from 23.56 to 432.59 µgm -3 ) were higher than TLV-TWA in the proximity of all indoor emission sources where some individuals were working. However, mean indoor and outdoor tobacco dust concentrations (7.71and 0.04 µgm-3 respectively) were lower than TLV-TWA. Totally 5 separated Ventilation systems and 5 centrifugal fans were designed and selcted to pull the air through 46 different hoods. Some downward slot hoods similar to VS-708 type were designed for the work-tables in tipping unit and some upward slot hoods that are similar to VS-903 type recommended by ACGIH's Industrial Ventilation committee were also selected for tipping manipulation unit. Some enclosing hoods were designed for feeders. Duct velocity of 1060 mmin -1 has been selected for all systems. Total air flow rates ranged from 240-369 m 3 min -1 . A very high efficient bag house containing several bag filters was used to collect dust. In conclusion, because of a high concentartion of tobacco dust in the proximity of sources and risk of workers exposure to tobacco dust, a suitable local exhaust Ventilation system was designed to reduce particulate air pollution concentrations in a tobacco processing factory. This study was carried out to evaluate tobacco dust concentration and also designing a suitable Ventilation system for reduction of tobacco dust concentration in a tobacco processing factory in the north of Iran.Gravimetric method was used to determine the tobacco dust concentrations in the emission sources an also indoor workplace. A local exhaust Ventilation system was designed according to the velocity pressure method recommended by ACGIH. Mean tobacco dust concentrations (ranged from 23.56 to 432.59 µgm -3 ) were higher than TLV-TWA in the proximity of all indoor emission sources where some individuals were working. However, mean indoor and outdoor tobacco dust concentrations (7.71and 0.04 µgm-3 respectively) were lower than TLV-TWA. Totally 5 separated Ventilation systems and 5 centrifugal fans were designed and selcted to pull the air through 46 different hoods. Some downward slot hoods similar to VS-708 type were designed for the work-tables in tipping unit and some upward slot hoods that are similar to VS-903 type recommended by ACGIH's Industrial Ventilation committee were also selected for tipping manipulation unit. Some enclosing hoods were designed for feeders. Duct velocity of 1060 mmin -1 has been selected for all systems. Total air flow rates ranged from 240-369 m 3 min -1 . A very high efficient bag house containing several bag filters was used to collect dust. In conclusion, because of a high concentartion of tobacco dust in the proximity of sources and risk of workers exposure to tobacco dust, a suitable local exhaust Ventilation system was designed to reduce particulate air pollution concentrations in a tobacco processing factory.