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M. Ghaffarpour - One of the best experts on this subject based on the ideXlab platform.

  • Spray Drop Size and Velocity Measurements in a Swirl
    2015
    Co-Authors: B. Chehroudi, M. Ghaffarpour
    Abstract:

    A pressure—swirl fuel nozzle generating a hollow—cone spray with nominal cone angle of 30 degrees is used in a swirl—stabilized combustor. The combustor is circular in cross section with swirl plate and fuel nozzle axes aligned and coinciding with the axis of the chamber. Kerosene is injected upward inside the chamber from the fuel nozzle. Separate swirl and Dilution Air flows are uniformly distributed into the chamber that pass through the honey comb flow straighteners and screens. Calculated swirl number of 1.5 is generated with the design swirl plate exit Air velocity of 30 degrees with respect to the chamber axis. Effects of swirl and Dilution Air flow rates on the shape and stability of the flame are investigated. Stable and classical liquid fuel sheet disintegration zone exists close to the nozzle with no visible light followed by a luminous blue region and a mixed blue/yellow region that subsequently turns into yellow for most of the part in the flame. A Phase Doppler Particle Analyzer (PDPA) is used to measure drop size, mean and rms axial velocity for two cases of with and without combustion at six different axial locations from the nozzle. For the no—combustion case all Air and fuel flow rates were kept at the same values as the combusting spray condition. Results for mean axial drop velocity profiles indicate widening of the spray due to combustion while the magnitudes of the peak velocities are slightly increased. No measurements inside the hollow—cone spray are possible due to burning of fuel droplets. Drop turbulence decreases due to combination of increase in gas kinematic viscosity and elimination of small drops at high temperatures. Sauter Mean Diameter (SMD) radial profiles at all axial locations increase with combustion due to preferential burning of small drops.

  • Experiments on Spray Combustion in a Gas Turbine Model Combustor
    Combustion Science and Technology, 1993
    Co-Authors: M. Ghaffarpour, B. Chehroudi
    Abstract:

    Abstract A hollow-cone kerosene spray with a nominal cone angle of 30 degrees from a pressure-swirl fuel atomizer was used in a swirl-stabilized combustor. Swirling Air flow with a calculated swirl number of 0.36 is generated with a swirl plate having an exit Air velocity vector of 30 degrees with respect to the chamber axis. Effects of swirl and Dilution Air flow rates on the shape and stability of the flame are investigated. A Phase Doppler Particle Analyzer (PDPA) is used to measure drop size, mean and rms values of axial drop velocity, fuel volume flux, drop velocity and size distributions, and size-classified drop velocity profiles for two cases of with and without combustion and at six different axial locations from the nozzle. A thermocouple is used to measure the uncorrected average temperature at these axial positions. For the no-combustion case all Air and fuel flow rates were kept at the same values as the combusting spray condition. A Laser Doppler Velocimeter (LDV) is employed to measure the ...

  • Structure of a Hollow-Cone Spray With and Without Combustion
    Volume 3: Coal Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations, 1992
    Co-Authors: B. Chehroudi, M. Ghaffarpour
    Abstract:

    A hollow-cone spray with a nominal cone angle of 30 degrees from a pressure-swirl fuel atomizer was used in a swirl-stabilized combustor. The combustor is circular in cross section, with a swirl plate and fuel nozzle axis coinciding with the axes of the chamber. kerosene is injected upward inside the chamber from the fuel nozzle. Separate swirl and Dilution Air flows are distributed into the chamber that pass through honeycomb flow straighteners and screens. A calculated swirl number of 1.5 is generated with the design swirl plate exit Air velocity of 30 degrees with respect to the chamber axis. Effects of swirl and Dilution Air flow rates on the shape and stability of the flame are investigated. A Phase Doppler Particle Analyzer (PDPA) is used to measure drop size, mean and rms values of axial drop velocity, fuel volume flux, drop velocity and size distributions, and sizeclassified drop velocity profiles for two cases of with and without combustion and at six different axial locations from the nozzle. For the no-combustion case all Air and fuel flow rates were kept at the same values as the combusting spray condition. Results for mean axial drop velocity profiles indicate widening of the spray, with slight increase in the magnitudes of the peak drop velocities due to combustion. Root mean square (RMS) values of drop velocity fluctuations decrease due to a combination of increase in gas kinematic viscosity and elimination of small drops at high temperatures. Sauter mean diameter (SMD) radial profiles at all axial locations increase with combustion due to preferential burning of small drops. Fuel volume flux profiles indicate negligible drop vaporization and/or burning up to a distance of 25mm from the nozzle. Velocity number distributions at different radial points for without combustion at an axial distance of 55mm from the atomizer are symmetric in shape only close to the peak of the mean drop velocity and show a bimodal shape around the maximum mean drop axial velocity gradient. Corresponding number distributions for the combustion case are fAirly symmetric and quite different in behavior at all radial positions. Sizeclassified drop velocity profiles are also plotted and discussed.

  • Spray Drop Size and Velocity Measurements in a Swirl-Stabilized Combustor
    Volume 3: Coal Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations, 1991
    Co-Authors: B. Chehroudi, M. Ghaffarpour
    Abstract:

    A pressure-swirl fuel nozzle generating a hollow-cone spray with nominal cone angle of 30 degrees is used in a swirl-stabilized combustor. The combustor is circular in cross section with swirl plate and fuel nozzle axes aligned and coinciding with the axis of the chamber. Kerosene is injected upward inside the chamber from the fuel nozzle. Separate swirl and Dilution Air flows are uniformly distributed into the chamber that pass through the honey comb flow straighteners and screens. Calculated swirl number of 1.5 is generated with the design swirl plate exit Air velocity of 30 degrees with respect to the chamber axis. Effects of swirl and Dilution Air flow rates on the shape and stability of the flame are investigated. Stable and classical liquid fuel sheet disintegration zone exists close to the nozzle with no visible light followed by a luminous blue region and a mixed blue/yellow region that subsequently turns into yellow for most of the part in the flame. A Phase Doppler Particle Analyzer (PDPA) is used to measure drop size, mean and rms axial velocity for two cases of with and without combustion at six different axial locations from the nozzle. For the no-combustion case all Air and fuel flow rates were kept at the same values as the combusting spray condition. Results for mean axial drop velocity profiles indicate widening of the spray due to combustion while the magnitudes of the peak velocities are slightly increased. No measurements inside the hollow-cone spray are possible due to burning of fuel droplets. Drop turbulence decreases due to combination of increase in gas kinematic viscosity and elimination of small drops at high temperatures. Sauter Mean Diameter (SMD) radial profiles at all axial locations increase with combustion due to preferential burning of small drops.Copyright © 1991 by ASME

B. Chehroudi - One of the best experts on this subject based on the ideXlab platform.

  • Spray Drop Size and Velocity Measurements in a Swirl
    2015
    Co-Authors: B. Chehroudi, M. Ghaffarpour
    Abstract:

    A pressure—swirl fuel nozzle generating a hollow—cone spray with nominal cone angle of 30 degrees is used in a swirl—stabilized combustor. The combustor is circular in cross section with swirl plate and fuel nozzle axes aligned and coinciding with the axis of the chamber. Kerosene is injected upward inside the chamber from the fuel nozzle. Separate swirl and Dilution Air flows are uniformly distributed into the chamber that pass through the honey comb flow straighteners and screens. Calculated swirl number of 1.5 is generated with the design swirl plate exit Air velocity of 30 degrees with respect to the chamber axis. Effects of swirl and Dilution Air flow rates on the shape and stability of the flame are investigated. Stable and classical liquid fuel sheet disintegration zone exists close to the nozzle with no visible light followed by a luminous blue region and a mixed blue/yellow region that subsequently turns into yellow for most of the part in the flame. A Phase Doppler Particle Analyzer (PDPA) is used to measure drop size, mean and rms axial velocity for two cases of with and without combustion at six different axial locations from the nozzle. For the no—combustion case all Air and fuel flow rates were kept at the same values as the combusting spray condition. Results for mean axial drop velocity profiles indicate widening of the spray due to combustion while the magnitudes of the peak velocities are slightly increased. No measurements inside the hollow—cone spray are possible due to burning of fuel droplets. Drop turbulence decreases due to combination of increase in gas kinematic viscosity and elimination of small drops at high temperatures. Sauter Mean Diameter (SMD) radial profiles at all axial locations increase with combustion due to preferential burning of small drops.

  • Experiments on Spray Combustion in a Gas Turbine Model Combustor
    Combustion Science and Technology, 1993
    Co-Authors: M. Ghaffarpour, B. Chehroudi
    Abstract:

    Abstract A hollow-cone kerosene spray with a nominal cone angle of 30 degrees from a pressure-swirl fuel atomizer was used in a swirl-stabilized combustor. Swirling Air flow with a calculated swirl number of 0.36 is generated with a swirl plate having an exit Air velocity vector of 30 degrees with respect to the chamber axis. Effects of swirl and Dilution Air flow rates on the shape and stability of the flame are investigated. A Phase Doppler Particle Analyzer (PDPA) is used to measure drop size, mean and rms values of axial drop velocity, fuel volume flux, drop velocity and size distributions, and size-classified drop velocity profiles for two cases of with and without combustion and at six different axial locations from the nozzle. A thermocouple is used to measure the uncorrected average temperature at these axial positions. For the no-combustion case all Air and fuel flow rates were kept at the same values as the combusting spray condition. A Laser Doppler Velocimeter (LDV) is employed to measure the ...

  • Structure of a Hollow-Cone Spray With and Without Combustion
    Volume 3: Coal Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations, 1992
    Co-Authors: B. Chehroudi, M. Ghaffarpour
    Abstract:

    A hollow-cone spray with a nominal cone angle of 30 degrees from a pressure-swirl fuel atomizer was used in a swirl-stabilized combustor. The combustor is circular in cross section, with a swirl plate and fuel nozzle axis coinciding with the axes of the chamber. kerosene is injected upward inside the chamber from the fuel nozzle. Separate swirl and Dilution Air flows are distributed into the chamber that pass through honeycomb flow straighteners and screens. A calculated swirl number of 1.5 is generated with the design swirl plate exit Air velocity of 30 degrees with respect to the chamber axis. Effects of swirl and Dilution Air flow rates on the shape and stability of the flame are investigated. A Phase Doppler Particle Analyzer (PDPA) is used to measure drop size, mean and rms values of axial drop velocity, fuel volume flux, drop velocity and size distributions, and sizeclassified drop velocity profiles for two cases of with and without combustion and at six different axial locations from the nozzle. For the no-combustion case all Air and fuel flow rates were kept at the same values as the combusting spray condition. Results for mean axial drop velocity profiles indicate widening of the spray, with slight increase in the magnitudes of the peak drop velocities due to combustion. Root mean square (RMS) values of drop velocity fluctuations decrease due to a combination of increase in gas kinematic viscosity and elimination of small drops at high temperatures. Sauter mean diameter (SMD) radial profiles at all axial locations increase with combustion due to preferential burning of small drops. Fuel volume flux profiles indicate negligible drop vaporization and/or burning up to a distance of 25mm from the nozzle. Velocity number distributions at different radial points for without combustion at an axial distance of 55mm from the atomizer are symmetric in shape only close to the peak of the mean drop velocity and show a bimodal shape around the maximum mean drop axial velocity gradient. Corresponding number distributions for the combustion case are fAirly symmetric and quite different in behavior at all radial positions. Sizeclassified drop velocity profiles are also plotted and discussed.

  • Spray Drop Size and Velocity Measurements in a Swirl-Stabilized Combustor
    Volume 3: Coal Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations, 1991
    Co-Authors: B. Chehroudi, M. Ghaffarpour
    Abstract:

    A pressure-swirl fuel nozzle generating a hollow-cone spray with nominal cone angle of 30 degrees is used in a swirl-stabilized combustor. The combustor is circular in cross section with swirl plate and fuel nozzle axes aligned and coinciding with the axis of the chamber. Kerosene is injected upward inside the chamber from the fuel nozzle. Separate swirl and Dilution Air flows are uniformly distributed into the chamber that pass through the honey comb flow straighteners and screens. Calculated swirl number of 1.5 is generated with the design swirl plate exit Air velocity of 30 degrees with respect to the chamber axis. Effects of swirl and Dilution Air flow rates on the shape and stability of the flame are investigated. Stable and classical liquid fuel sheet disintegration zone exists close to the nozzle with no visible light followed by a luminous blue region and a mixed blue/yellow region that subsequently turns into yellow for most of the part in the flame. A Phase Doppler Particle Analyzer (PDPA) is used to measure drop size, mean and rms axial velocity for two cases of with and without combustion at six different axial locations from the nozzle. For the no-combustion case all Air and fuel flow rates were kept at the same values as the combusting spray condition. Results for mean axial drop velocity profiles indicate widening of the spray due to combustion while the magnitudes of the peak velocities are slightly increased. No measurements inside the hollow-cone spray are possible due to burning of fuel droplets. Drop turbulence decreases due to combination of increase in gas kinematic viscosity and elimination of small drops at high temperatures. Sauter Mean Diameter (SMD) radial profiles at all axial locations increase with combustion due to preferential burning of small drops.Copyright © 1991 by ASME

Xinghua Li - One of the best experts on this subject based on the ideXlab platform.

  • Development of a Dilution sampler for measuring fine particle from stationary sources
    Huanjing Kexue Xuebao Acta Scientiae Circumstantiae, 2015
    Co-Authors: Xinghua Li, Jianguo Deng, Yang Cao, Lei Duan, Jingkun Jiang, Qiang Zhang, Junzan Han
    Abstract:

    A compact Dilution sampler was developed to measure fine particles from stationary sources. The sampler could simulate the cooling, Dilution and condensation process and collect primary PM2.5after the hot flue gas left the stack. Main technical parameters of the Dilution sampler were Dilution ratio from 20:1 to 50:1, residence time of 10 seconds, temperature and relative humidity of the sampling gas after Dilution less than 42℃ and 70%, respectively, which satisfied ISO 25597: 2013. Performance assessment of the Dilution sampler in the laboratory showed excellent Air tightness and extremely low fine particle concentration in the Dilution Air. Fine mixing of sampling gas and Dilution Air was achieved, and fine particle loss in the sampler was acceptable, which indicated that the Dilution sampler is excellent and suitable for measuring fine particles from stationary sources.

  • Design of a compact Dilution sampler for stationary combustion sources.
    Journal of The Air & Waste Management Association, 2011
    Co-Authors: Xinghua Li, Shuxiao Wang, Lei Duan, Zhengwei Long
    Abstract:

    ABSTRACT The Dilution sampling method simulates the rapid cooling and Dilution processes after hot flue gas have left the stack. This allows gases or vapors to nucleate both homogeneously and heterogeneously, and to condense on preexisting particles in processes analogous to those that occur in the ambient environment. Using this method the authors can collect filterable particulate matter (PM) and condensible PM, that is, primary PM, simultaneously. In order to make this method more suitable for field investigation, a compact Dilution sampler was developed. The sampler enhances mixing of Dilution Air with the stack gas, and thus shortens the length of the mixing section. The design decreases the nominal flow rate through the aging section, and accordingly reduces the size of the residence chamber. The decreased size of the sampler is suitable for field test. Sampling gas is pressured into the residence chamber, and Air pressure in the chamber is micro-positive. Uncollected redundant gas is automatically ...

  • Journal of the Air & Waste Management Association Design of a Compact Dilution Sampler for Stationary Combustion Sources Design of a Compact Dilution Sampler for Stationary Combustion Sources
    Journal of the Air & Waste Management Association J. Air & Waste Manage. Assoc, 2011
    Co-Authors: Xinghua Li, Lei Duan, Jiming Hao, Shuxiao Wang, Zhengwei Long
    Abstract:

    The Dilution sampling method simulates the rapid cooling and Dilution processes after hot flue gas have left the stack. This allows gases or vapors to nucleate both homoge-neously and heterogeneously, and to condense on preex-isting particles in processes analogous to those that occur in the ambient environment. Using this method the authors can collect filterable particulate matter (PM) and condensi-ble PM, that is, primary PM, simultaneously. In order to make this method more suitable for field investigation, a compact Dilution sampler was developed. The sampler enhances mixing of Dilution Air with the stack gas, and thus shortens the length of the mixing section. The design decreases the nominal flow rate through the aging section, and accordingly reduces the size of the residence chamber. The decreased size of the sampler is suitable for field test.

Zhengwei Long - One of the best experts on this subject based on the ideXlab platform.

  • Design of a compact Dilution sampler for stationary combustion sources.
    Journal of The Air & Waste Management Association, 2011
    Co-Authors: Xinghua Li, Shuxiao Wang, Lei Duan, Zhengwei Long
    Abstract:

    ABSTRACT The Dilution sampling method simulates the rapid cooling and Dilution processes after hot flue gas have left the stack. This allows gases or vapors to nucleate both homogeneously and heterogeneously, and to condense on preexisting particles in processes analogous to those that occur in the ambient environment. Using this method the authors can collect filterable particulate matter (PM) and condensible PM, that is, primary PM, simultaneously. In order to make this method more suitable for field investigation, a compact Dilution sampler was developed. The sampler enhances mixing of Dilution Air with the stack gas, and thus shortens the length of the mixing section. The design decreases the nominal flow rate through the aging section, and accordingly reduces the size of the residence chamber. The decreased size of the sampler is suitable for field test. Sampling gas is pressured into the residence chamber, and Air pressure in the chamber is micro-positive. Uncollected redundant gas is automatically ...

  • Journal of the Air & Waste Management Association Design of a Compact Dilution Sampler for Stationary Combustion Sources Design of a Compact Dilution Sampler for Stationary Combustion Sources
    Journal of the Air & Waste Management Association J. Air & Waste Manage. Assoc, 2011
    Co-Authors: Xinghua Li, Lei Duan, Jiming Hao, Shuxiao Wang, Zhengwei Long
    Abstract:

    The Dilution sampling method simulates the rapid cooling and Dilution processes after hot flue gas have left the stack. This allows gases or vapors to nucleate both homoge-neously and heterogeneously, and to condense on preex-isting particles in processes analogous to those that occur in the ambient environment. Using this method the authors can collect filterable particulate matter (PM) and condensi-ble PM, that is, primary PM, simultaneously. In order to make this method more suitable for field investigation, a compact Dilution sampler was developed. The sampler enhances mixing of Dilution Air with the stack gas, and thus shortens the length of the mixing section. The design decreases the nominal flow rate through the aging section, and accordingly reduces the size of the residence chamber. The decreased size of the sampler is suitable for field test.

Lei Duan - One of the best experts on this subject based on the ideXlab platform.

  • Development of a Dilution sampler for measuring fine particle from stationary sources
    Huanjing Kexue Xuebao Acta Scientiae Circumstantiae, 2015
    Co-Authors: Xinghua Li, Jianguo Deng, Yang Cao, Lei Duan, Jingkun Jiang, Qiang Zhang, Junzan Han
    Abstract:

    A compact Dilution sampler was developed to measure fine particles from stationary sources. The sampler could simulate the cooling, Dilution and condensation process and collect primary PM2.5after the hot flue gas left the stack. Main technical parameters of the Dilution sampler were Dilution ratio from 20:1 to 50:1, residence time of 10 seconds, temperature and relative humidity of the sampling gas after Dilution less than 42℃ and 70%, respectively, which satisfied ISO 25597: 2013. Performance assessment of the Dilution sampler in the laboratory showed excellent Air tightness and extremely low fine particle concentration in the Dilution Air. Fine mixing of sampling gas and Dilution Air was achieved, and fine particle loss in the sampler was acceptable, which indicated that the Dilution sampler is excellent and suitable for measuring fine particles from stationary sources.

  • Design of a compact Dilution sampler for stationary combustion sources.
    Journal of The Air & Waste Management Association, 2011
    Co-Authors: Xinghua Li, Shuxiao Wang, Lei Duan, Zhengwei Long
    Abstract:

    ABSTRACT The Dilution sampling method simulates the rapid cooling and Dilution processes after hot flue gas have left the stack. This allows gases or vapors to nucleate both homogeneously and heterogeneously, and to condense on preexisting particles in processes analogous to those that occur in the ambient environment. Using this method the authors can collect filterable particulate matter (PM) and condensible PM, that is, primary PM, simultaneously. In order to make this method more suitable for field investigation, a compact Dilution sampler was developed. The sampler enhances mixing of Dilution Air with the stack gas, and thus shortens the length of the mixing section. The design decreases the nominal flow rate through the aging section, and accordingly reduces the size of the residence chamber. The decreased size of the sampler is suitable for field test. Sampling gas is pressured into the residence chamber, and Air pressure in the chamber is micro-positive. Uncollected redundant gas is automatically ...

  • Journal of the Air & Waste Management Association Design of a Compact Dilution Sampler for Stationary Combustion Sources Design of a Compact Dilution Sampler for Stationary Combustion Sources
    Journal of the Air & Waste Management Association J. Air & Waste Manage. Assoc, 2011
    Co-Authors: Xinghua Li, Lei Duan, Jiming Hao, Shuxiao Wang, Zhengwei Long
    Abstract:

    The Dilution sampling method simulates the rapid cooling and Dilution processes after hot flue gas have left the stack. This allows gases or vapors to nucleate both homoge-neously and heterogeneously, and to condense on preex-isting particles in processes analogous to those that occur in the ambient environment. Using this method the authors can collect filterable particulate matter (PM) and condensi-ble PM, that is, primary PM, simultaneously. In order to make this method more suitable for field investigation, a compact Dilution sampler was developed. The sampler enhances mixing of Dilution Air with the stack gas, and thus shortens the length of the mixing section. The design decreases the nominal flow rate through the aging section, and accordingly reduces the size of the residence chamber. The decreased size of the sampler is suitable for field test.