The Experts below are selected from a list of 97275 Experts worldwide ranked by ideXlab platform

Qingyan Chen - One of the best experts on this subject based on the ideXlab platform.

  • Study of particle deposition on the complex components of Environmental Control Systems
    2019
    Co-Authors: Qing Cao, Daniel Wei, Chao-hsin Lin, Zhipeng Deng, Qingyan Chen
    Abstract:

    Abstract As most airplanes do not have HEPA filters for filtering outside air, particulate matter in the outdoor air can deposit on the Environmental Control Systems (ECS) of the airplanes. The particles that accumulate on the various surfaces of the ECS components can affect their thermal performance and may lead to component failures. This study experimentally and numerically investigated the particle deposition on a heat exchanger and a turbocharger, which are key components of ECS with complex geometry. A test rig was built to obtain the monodisperse particle deposition fractions by measuring the particle concentration upstream and downstream of the components with the weighing method. The tested particles ranged from 1 to 8 μm in diameter. Different Reynolds-averaged Navier-Stokes (RANS) models, together with a modified Lagrangian method, were used to predict the total particle deposition fractions in the tested components. The computed particle deposition was compared with the experimental data. The results showed that the RNG k-e model with near-wall correction provided the most accurate prediction of the particle deposition fraction on the heat exchanger and turbocharger. The particle deposition fraction increased significantly with the particle size. CFD simulation provided detailed information about the particle deposition distribution inside the heat exchanger and turbocharger. The location and number of deposited particles depended mainly on the particle size and air velocity. This investigation identified a suitable tool for studying particle deposition in the ECS of commercial airplanes.

  • in flight monitoring of particle deposition in the Environmental Control Systems of commercial airliners in china
    2017
    Co-Authors: Qing Cao, Daniel Wei, Chao-hsin Lin, Qingyan Chen, Wei Liu, Steven L Baughcum, Sharon L Norris
    Abstract:

    Abstract Severe air pollution and low on-time performance of commercial flights in China could increase particle deposition in the Environmental Control Systems (ECSs) of commercial airliners. The particles deposited in the ECSs could negatively affect the performance of the airplanes. In addition, particles that penetrate into the aircraft cabin could adversely impact the health of passengers and crew members. This investigation conducted simultaneous measurements of particle mass concentration and size distribution inside and outside the cabin during 64 commercial flights of Boeing 737 and Airbus 320 aircraft departing from or arriving at Tianjin Airport in China. The results showed that the PM2.5 mass concentration deposition in the ECSs of these airplanes ranged from 50% to 90%, which was much higher than that measured in an airplane with a ground air-conditioning unit. The average deposition rates of particles with diameters of 0.5–1 μm, 1–2 μm, 2–5 μm, 5–10 μm, and >10 μm were 89 ± 8%, 85 ± 13%, 80 ± 13%, 73 ± 15%, and 80 ± 14%, respectively. The in-flight measurement results indicated that the particle concentration in the breathing zone was higher than that in the air-supply zone, which implies a significant contribution by particles in the interior of the cabin. Such particles come from human emissions or particle resuspension from interior surfaces.

  • numerical modeling of particle deposition in the Environmental Control Systems of commercial airliners on ground
    2017
    Co-Authors: Yudi Liu, Daniel Wei, Xiong Shen, Chao-hsin Lin, Zhengwei Long, Qing Cao, Wei Liu, Steven L Baughcum, Qingyan Chen
    Abstract:

    The Environmental Control system (ECS) of a commercial airplane supplies air to the cabin in order to maintain a safe, comfortable, and healthy environment for passengers and crew members. Because about half of the air supplied to the cabin is outside air, atmosphere particles could deposit in the ECS before entering the cabin. This investigation developed a model to calculate the particle deposition rates in the ECS for different particle sizes on the basis of a set of empirical equations from the literature. The model was used to predict particle deposition in five types of commercial airplanes (a regional jet, Boeing 737-800, Airbus 319, Airbus 320, and MD-82). The predicted results were compared with data measured in-flight or during operation on the ground and agreed well with the measured data. Both the simulated and measured results showed that almost all the large particles (d p ≥ 5.0 μm) and 75% of small particles (d p = 0.3–5.0 μm) were deposited in the ECS. Most of the particle deposition occurred near the entrance to the ECS where the geometry was the most complex.

  • Modeling dynamic responses of aircraft Environmental Control Systems by coupling with cabin thermal environment simulations
    2016
    Co-Authors: Haishen Yin, Zhuangbo Feng, Daniel Wei, Balasubramanyam Sasanapuri, Xiong Shen, Ran Duan, Chao-hsin Lin, Zhengwei Long, Yan Huang, Qingyan Chen
    Abstract:

    Commercial aircraft use Environmental Control Systems (ECSs) to Control the thermal environment in cabins and thus ensure passengers’ safety, health, and comfort. This study investigated the interaction between ECS operation and cabin thermal environment. Simplified models were developed for the thermodynamic processes of the key ECS components in a commercial software program, ANSYS Simplorer. A computational fluid dynamics (CFD) program, ANSYS Fluent, was employed to simulate the thermal environment in a cabin. Through the coupling of Simplorer and Fluent, a PID Control method was applied to the aircraft ECS in Simplorer to achieve dynamic Control of the temperature of the supply air to the cabin, which was used as a Fluent input. The calculated supply air temperature agreed with the corresponding experimental data obtained from an MD-82 aircraft on the ground. The coupled model was then used to simulate a complete flight for the purpose of studying the interaction between ECS operation and the cabin thermal environment. The results show that the PID Controller in the ECS can maintain the cabin air temperature within ±0.6 K of the set point, with an acceptable air temperature distribution. The coupled models can be used for the design and analysis of the ECS and cabin thermal environment for commercial airplanes.

Wei Liu - One of the best experts on this subject based on the ideXlab platform.

  • numerical modeling of particle deposition in the Environmental Control Systems of commercial airliners on ground
    2017
    Co-Authors: Yudi Liu, Daniel Wei, Xiong Shen, Chao-hsin Lin, Zhengwei Long, Qing Cao, Wei Liu, Steven L Baughcum, Qingyan Chen
    Abstract:

    The Environmental Control system (ECS) of a commercial airplane supplies air to the cabin in order to maintain a safe, comfortable, and healthy environment for passengers and crew members. Because about half of the air supplied to the cabin is outside air, atmosphere particles could deposit in the ECS before entering the cabin. This investigation developed a model to calculate the particle deposition rates in the ECS for different particle sizes on the basis of a set of empirical equations from the literature. The model was used to predict particle deposition in five types of commercial airplanes (a regional jet, Boeing 737-800, Airbus 319, Airbus 320, and MD-82). The predicted results were compared with data measured in-flight or during operation on the ground and agreed well with the measured data. Both the simulated and measured results showed that almost all the large particles (d p ≥ 5.0 μm) and 75% of small particles (d p = 0.3–5.0 μm) were deposited in the ECS. Most of the particle deposition occurred near the entrance to the ECS where the geometry was the most complex.

  • in flight monitoring of particle deposition in the Environmental Control Systems of commercial airliners in china
    2017
    Co-Authors: Qing Cao, Daniel Wei, Chao-hsin Lin, Qingyan Chen, Wei Liu, Steven L Baughcum, Sharon L Norris
    Abstract:

    Abstract Severe air pollution and low on-time performance of commercial flights in China could increase particle deposition in the Environmental Control Systems (ECSs) of commercial airliners. The particles deposited in the ECSs could negatively affect the performance of the airplanes. In addition, particles that penetrate into the aircraft cabin could adversely impact the health of passengers and crew members. This investigation conducted simultaneous measurements of particle mass concentration and size distribution inside and outside the cabin during 64 commercial flights of Boeing 737 and Airbus 320 aircraft departing from or arriving at Tianjin Airport in China. The results showed that the PM2.5 mass concentration deposition in the ECSs of these airplanes ranged from 50% to 90%, which was much higher than that measured in an airplane with a ground air-conditioning unit. The average deposition rates of particles with diameters of 0.5–1 μm, 1–2 μm, 2–5 μm, 5–10 μm, and >10 μm were 89 ± 8%, 85 ± 13%, 80 ± 13%, 73 ± 15%, and 80 ± 14%, respectively. The in-flight measurement results indicated that the particle concentration in the breathing zone was higher than that in the air-supply zone, which implies a significant contribution by particles in the interior of the cabin. Such particles come from human emissions or particle resuspension from interior surfaces.

  • experimental study of particle deposition in the Environmental Control Systems of commercial airliners
    2016
    Co-Authors: Qing Cao, Daniel Wei, Xiong Shen, Chao-hsin Lin, Yudi Liu, Wei Liu, Steven L Baughcum, Sharon L Norris, Zhengwei Long
    Abstract:

    Abstract Serious air pollution and low on-time performance of commercial flights in China could result in more particles being deposited in the Environmental Control Systems (ECS) of the commercial airliners and ground air-conditioning carts (GAC). The particle deposited in the ECS and GAC could cause performance issues of the airplanes and GAC. In addition, particles penetrated to the aircraft cabin could cause adverse health impact on the passengers and crew. This investigation measured the PM 2.5 particle concentrations and the quantities of particles of different sizes at the inlet and outlet of the GAC and ECS in an MD-82 airplane parked next to Tianjin Airport under different air quality levels. The results showed that the deposition rate of the PM 2.5 mass in the GAC and ECS was 40–50%, with most (30–40%) of the deposition occurring in the ECS. For particles with a diameter of 5 μm or larger, the deposition rate was greater than 90%. For particles with a diameter of 0.5 μm or less, the deposition rate was less than 25% so they entered into the aircraft cabin. In addition, particle mass and number concentration was measured on commercial flights. The results indicated that particle concentrations were high compared with that during the cruising when the airplanes were on the ground at the Chinese airports where ambient particle concentrations were also high.

Qing Cao - One of the best experts on this subject based on the ideXlab platform.

  • Study of particle deposition on the complex components of Environmental Control Systems
    2019
    Co-Authors: Qing Cao, Daniel Wei, Chao-hsin Lin, Zhipeng Deng, Qingyan Chen
    Abstract:

    Abstract As most airplanes do not have HEPA filters for filtering outside air, particulate matter in the outdoor air can deposit on the Environmental Control Systems (ECS) of the airplanes. The particles that accumulate on the various surfaces of the ECS components can affect their thermal performance and may lead to component failures. This study experimentally and numerically investigated the particle deposition on a heat exchanger and a turbocharger, which are key components of ECS with complex geometry. A test rig was built to obtain the monodisperse particle deposition fractions by measuring the particle concentration upstream and downstream of the components with the weighing method. The tested particles ranged from 1 to 8 μm in diameter. Different Reynolds-averaged Navier-Stokes (RANS) models, together with a modified Lagrangian method, were used to predict the total particle deposition fractions in the tested components. The computed particle deposition was compared with the experimental data. The results showed that the RNG k-e model with near-wall correction provided the most accurate prediction of the particle deposition fraction on the heat exchanger and turbocharger. The particle deposition fraction increased significantly with the particle size. CFD simulation provided detailed information about the particle deposition distribution inside the heat exchanger and turbocharger. The location and number of deposited particles depended mainly on the particle size and air velocity. This investigation identified a suitable tool for studying particle deposition in the ECS of commercial airplanes.

  • in flight monitoring of particle deposition in the Environmental Control Systems of commercial airliners in china
    2017
    Co-Authors: Qing Cao, Daniel Wei, Chao-hsin Lin, Qingyan Chen, Wei Liu, Steven L Baughcum, Sharon L Norris
    Abstract:

    Abstract Severe air pollution and low on-time performance of commercial flights in China could increase particle deposition in the Environmental Control Systems (ECSs) of commercial airliners. The particles deposited in the ECSs could negatively affect the performance of the airplanes. In addition, particles that penetrate into the aircraft cabin could adversely impact the health of passengers and crew members. This investigation conducted simultaneous measurements of particle mass concentration and size distribution inside and outside the cabin during 64 commercial flights of Boeing 737 and Airbus 320 aircraft departing from or arriving at Tianjin Airport in China. The results showed that the PM2.5 mass concentration deposition in the ECSs of these airplanes ranged from 50% to 90%, which was much higher than that measured in an airplane with a ground air-conditioning unit. The average deposition rates of particles with diameters of 0.5–1 μm, 1–2 μm, 2–5 μm, 5–10 μm, and >10 μm were 89 ± 8%, 85 ± 13%, 80 ± 13%, 73 ± 15%, and 80 ± 14%, respectively. The in-flight measurement results indicated that the particle concentration in the breathing zone was higher than that in the air-supply zone, which implies a significant contribution by particles in the interior of the cabin. Such particles come from human emissions or particle resuspension from interior surfaces.

  • numerical modeling of particle deposition in the Environmental Control Systems of commercial airliners on ground
    2017
    Co-Authors: Yudi Liu, Daniel Wei, Xiong Shen, Chao-hsin Lin, Zhengwei Long, Qing Cao, Wei Liu, Steven L Baughcum, Qingyan Chen
    Abstract:

    The Environmental Control system (ECS) of a commercial airplane supplies air to the cabin in order to maintain a safe, comfortable, and healthy environment for passengers and crew members. Because about half of the air supplied to the cabin is outside air, atmosphere particles could deposit in the ECS before entering the cabin. This investigation developed a model to calculate the particle deposition rates in the ECS for different particle sizes on the basis of a set of empirical equations from the literature. The model was used to predict particle deposition in five types of commercial airplanes (a regional jet, Boeing 737-800, Airbus 319, Airbus 320, and MD-82). The predicted results were compared with data measured in-flight or during operation on the ground and agreed well with the measured data. Both the simulated and measured results showed that almost all the large particles (d p ≥ 5.0 μm) and 75% of small particles (d p = 0.3–5.0 μm) were deposited in the ECS. Most of the particle deposition occurred near the entrance to the ECS where the geometry was the most complex.

  • experimental study of particle deposition in the Environmental Control Systems of commercial airliners
    2016
    Co-Authors: Qing Cao, Daniel Wei, Xiong Shen, Chao-hsin Lin, Yudi Liu, Wei Liu, Steven L Baughcum, Sharon L Norris, Zhengwei Long
    Abstract:

    Abstract Serious air pollution and low on-time performance of commercial flights in China could result in more particles being deposited in the Environmental Control Systems (ECS) of the commercial airliners and ground air-conditioning carts (GAC). The particle deposited in the ECS and GAC could cause performance issues of the airplanes and GAC. In addition, particles penetrated to the aircraft cabin could cause adverse health impact on the passengers and crew. This investigation measured the PM 2.5 particle concentrations and the quantities of particles of different sizes at the inlet and outlet of the GAC and ECS in an MD-82 airplane parked next to Tianjin Airport under different air quality levels. The results showed that the deposition rate of the PM 2.5 mass in the GAC and ECS was 40–50%, with most (30–40%) of the deposition occurring in the ECS. For particles with a diameter of 5 μm or larger, the deposition rate was greater than 90%. For particles with a diameter of 0.5 μm or less, the deposition rate was less than 25% so they entered into the aircraft cabin. In addition, particle mass and number concentration was measured on commercial flights. The results indicated that particle concentrations were high compared with that during the cruising when the airplanes were on the ground at the Chinese airports where ambient particle concentrations were also high.

Daniel Wei - One of the best experts on this subject based on the ideXlab platform.

  • Study of particle deposition on the complex components of Environmental Control Systems
    2019
    Co-Authors: Qing Cao, Daniel Wei, Chao-hsin Lin, Zhipeng Deng, Qingyan Chen
    Abstract:

    Abstract As most airplanes do not have HEPA filters for filtering outside air, particulate matter in the outdoor air can deposit on the Environmental Control Systems (ECS) of the airplanes. The particles that accumulate on the various surfaces of the ECS components can affect their thermal performance and may lead to component failures. This study experimentally and numerically investigated the particle deposition on a heat exchanger and a turbocharger, which are key components of ECS with complex geometry. A test rig was built to obtain the monodisperse particle deposition fractions by measuring the particle concentration upstream and downstream of the components with the weighing method. The tested particles ranged from 1 to 8 μm in diameter. Different Reynolds-averaged Navier-Stokes (RANS) models, together with a modified Lagrangian method, were used to predict the total particle deposition fractions in the tested components. The computed particle deposition was compared with the experimental data. The results showed that the RNG k-e model with near-wall correction provided the most accurate prediction of the particle deposition fraction on the heat exchanger and turbocharger. The particle deposition fraction increased significantly with the particle size. CFD simulation provided detailed information about the particle deposition distribution inside the heat exchanger and turbocharger. The location and number of deposited particles depended mainly on the particle size and air velocity. This investigation identified a suitable tool for studying particle deposition in the ECS of commercial airplanes.

  • in flight monitoring of particle deposition in the Environmental Control Systems of commercial airliners in china
    2017
    Co-Authors: Qing Cao, Daniel Wei, Chao-hsin Lin, Qingyan Chen, Wei Liu, Steven L Baughcum, Sharon L Norris
    Abstract:

    Abstract Severe air pollution and low on-time performance of commercial flights in China could increase particle deposition in the Environmental Control Systems (ECSs) of commercial airliners. The particles deposited in the ECSs could negatively affect the performance of the airplanes. In addition, particles that penetrate into the aircraft cabin could adversely impact the health of passengers and crew members. This investigation conducted simultaneous measurements of particle mass concentration and size distribution inside and outside the cabin during 64 commercial flights of Boeing 737 and Airbus 320 aircraft departing from or arriving at Tianjin Airport in China. The results showed that the PM2.5 mass concentration deposition in the ECSs of these airplanes ranged from 50% to 90%, which was much higher than that measured in an airplane with a ground air-conditioning unit. The average deposition rates of particles with diameters of 0.5–1 μm, 1–2 μm, 2–5 μm, 5–10 μm, and >10 μm were 89 ± 8%, 85 ± 13%, 80 ± 13%, 73 ± 15%, and 80 ± 14%, respectively. The in-flight measurement results indicated that the particle concentration in the breathing zone was higher than that in the air-supply zone, which implies a significant contribution by particles in the interior of the cabin. Such particles come from human emissions or particle resuspension from interior surfaces.

  • numerical modeling of particle deposition in the Environmental Control Systems of commercial airliners on ground
    2017
    Co-Authors: Yudi Liu, Daniel Wei, Xiong Shen, Chao-hsin Lin, Zhengwei Long, Qing Cao, Wei Liu, Steven L Baughcum, Qingyan Chen
    Abstract:

    The Environmental Control system (ECS) of a commercial airplane supplies air to the cabin in order to maintain a safe, comfortable, and healthy environment for passengers and crew members. Because about half of the air supplied to the cabin is outside air, atmosphere particles could deposit in the ECS before entering the cabin. This investigation developed a model to calculate the particle deposition rates in the ECS for different particle sizes on the basis of a set of empirical equations from the literature. The model was used to predict particle deposition in five types of commercial airplanes (a regional jet, Boeing 737-800, Airbus 319, Airbus 320, and MD-82). The predicted results were compared with data measured in-flight or during operation on the ground and agreed well with the measured data. Both the simulated and measured results showed that almost all the large particles (d p ≥ 5.0 μm) and 75% of small particles (d p = 0.3–5.0 μm) were deposited in the ECS. Most of the particle deposition occurred near the entrance to the ECS where the geometry was the most complex.

  • Modeling dynamic responses of aircraft Environmental Control Systems by coupling with cabin thermal environment simulations
    2016
    Co-Authors: Haishen Yin, Zhuangbo Feng, Daniel Wei, Balasubramanyam Sasanapuri, Xiong Shen, Ran Duan, Chao-hsin Lin, Zhengwei Long, Yan Huang, Qingyan Chen
    Abstract:

    Commercial aircraft use Environmental Control Systems (ECSs) to Control the thermal environment in cabins and thus ensure passengers’ safety, health, and comfort. This study investigated the interaction between ECS operation and cabin thermal environment. Simplified models were developed for the thermodynamic processes of the key ECS components in a commercial software program, ANSYS Simplorer. A computational fluid dynamics (CFD) program, ANSYS Fluent, was employed to simulate the thermal environment in a cabin. Through the coupling of Simplorer and Fluent, a PID Control method was applied to the aircraft ECS in Simplorer to achieve dynamic Control of the temperature of the supply air to the cabin, which was used as a Fluent input. The calculated supply air temperature agreed with the corresponding experimental data obtained from an MD-82 aircraft on the ground. The coupled model was then used to simulate a complete flight for the purpose of studying the interaction between ECS operation and the cabin thermal environment. The results show that the PID Controller in the ECS can maintain the cabin air temperature within ±0.6 K of the set point, with an acceptable air temperature distribution. The coupled models can be used for the design and analysis of the ECS and cabin thermal environment for commercial airplanes.

  • experimental study of particle deposition in the Environmental Control Systems of commercial airliners
    2016
    Co-Authors: Qing Cao, Daniel Wei, Xiong Shen, Chao-hsin Lin, Yudi Liu, Wei Liu, Steven L Baughcum, Sharon L Norris, Zhengwei Long
    Abstract:

    Abstract Serious air pollution and low on-time performance of commercial flights in China could result in more particles being deposited in the Environmental Control Systems (ECS) of the commercial airliners and ground air-conditioning carts (GAC). The particle deposited in the ECS and GAC could cause performance issues of the airplanes and GAC. In addition, particles penetrated to the aircraft cabin could cause adverse health impact on the passengers and crew. This investigation measured the PM 2.5 particle concentrations and the quantities of particles of different sizes at the inlet and outlet of the GAC and ECS in an MD-82 airplane parked next to Tianjin Airport under different air quality levels. The results showed that the deposition rate of the PM 2.5 mass in the GAC and ECS was 40–50%, with most (30–40%) of the deposition occurring in the ECS. For particles with a diameter of 5 μm or larger, the deposition rate was greater than 90%. For particles with a diameter of 0.5 μm or less, the deposition rate was less than 25% so they entered into the aircraft cabin. In addition, particle mass and number concentration was measured on commercial flights. The results indicated that particle concentrations were high compared with that during the cruising when the airplanes were on the ground at the Chinese airports where ambient particle concentrations were also high.

Chao-hsin Lin - One of the best experts on this subject based on the ideXlab platform.

  • Study of particle deposition on the complex components of Environmental Control Systems
    2019
    Co-Authors: Qing Cao, Daniel Wei, Chao-hsin Lin, Zhipeng Deng, Qingyan Chen
    Abstract:

    Abstract As most airplanes do not have HEPA filters for filtering outside air, particulate matter in the outdoor air can deposit on the Environmental Control Systems (ECS) of the airplanes. The particles that accumulate on the various surfaces of the ECS components can affect their thermal performance and may lead to component failures. This study experimentally and numerically investigated the particle deposition on a heat exchanger and a turbocharger, which are key components of ECS with complex geometry. A test rig was built to obtain the monodisperse particle deposition fractions by measuring the particle concentration upstream and downstream of the components with the weighing method. The tested particles ranged from 1 to 8 μm in diameter. Different Reynolds-averaged Navier-Stokes (RANS) models, together with a modified Lagrangian method, were used to predict the total particle deposition fractions in the tested components. The computed particle deposition was compared with the experimental data. The results showed that the RNG k-e model with near-wall correction provided the most accurate prediction of the particle deposition fraction on the heat exchanger and turbocharger. The particle deposition fraction increased significantly with the particle size. CFD simulation provided detailed information about the particle deposition distribution inside the heat exchanger and turbocharger. The location and number of deposited particles depended mainly on the particle size and air velocity. This investigation identified a suitable tool for studying particle deposition in the ECS of commercial airplanes.

  • in flight monitoring of particle deposition in the Environmental Control Systems of commercial airliners in china
    2017
    Co-Authors: Qing Cao, Daniel Wei, Chao-hsin Lin, Qingyan Chen, Wei Liu, Steven L Baughcum, Sharon L Norris
    Abstract:

    Abstract Severe air pollution and low on-time performance of commercial flights in China could increase particle deposition in the Environmental Control Systems (ECSs) of commercial airliners. The particles deposited in the ECSs could negatively affect the performance of the airplanes. In addition, particles that penetrate into the aircraft cabin could adversely impact the health of passengers and crew members. This investigation conducted simultaneous measurements of particle mass concentration and size distribution inside and outside the cabin during 64 commercial flights of Boeing 737 and Airbus 320 aircraft departing from or arriving at Tianjin Airport in China. The results showed that the PM2.5 mass concentration deposition in the ECSs of these airplanes ranged from 50% to 90%, which was much higher than that measured in an airplane with a ground air-conditioning unit. The average deposition rates of particles with diameters of 0.5–1 μm, 1–2 μm, 2–5 μm, 5–10 μm, and >10 μm were 89 ± 8%, 85 ± 13%, 80 ± 13%, 73 ± 15%, and 80 ± 14%, respectively. The in-flight measurement results indicated that the particle concentration in the breathing zone was higher than that in the air-supply zone, which implies a significant contribution by particles in the interior of the cabin. Such particles come from human emissions or particle resuspension from interior surfaces.

  • numerical modeling of particle deposition in the Environmental Control Systems of commercial airliners on ground
    2017
    Co-Authors: Yudi Liu, Daniel Wei, Xiong Shen, Chao-hsin Lin, Zhengwei Long, Qing Cao, Wei Liu, Steven L Baughcum, Qingyan Chen
    Abstract:

    The Environmental Control system (ECS) of a commercial airplane supplies air to the cabin in order to maintain a safe, comfortable, and healthy environment for passengers and crew members. Because about half of the air supplied to the cabin is outside air, atmosphere particles could deposit in the ECS before entering the cabin. This investigation developed a model to calculate the particle deposition rates in the ECS for different particle sizes on the basis of a set of empirical equations from the literature. The model was used to predict particle deposition in five types of commercial airplanes (a regional jet, Boeing 737-800, Airbus 319, Airbus 320, and MD-82). The predicted results were compared with data measured in-flight or during operation on the ground and agreed well with the measured data. Both the simulated and measured results showed that almost all the large particles (d p ≥ 5.0 μm) and 75% of small particles (d p = 0.3–5.0 μm) were deposited in the ECS. Most of the particle deposition occurred near the entrance to the ECS where the geometry was the most complex.

  • Modeling dynamic responses of aircraft Environmental Control Systems by coupling with cabin thermal environment simulations
    2016
    Co-Authors: Haishen Yin, Zhuangbo Feng, Daniel Wei, Balasubramanyam Sasanapuri, Xiong Shen, Ran Duan, Chao-hsin Lin, Zhengwei Long, Yan Huang, Qingyan Chen
    Abstract:

    Commercial aircraft use Environmental Control Systems (ECSs) to Control the thermal environment in cabins and thus ensure passengers’ safety, health, and comfort. This study investigated the interaction between ECS operation and cabin thermal environment. Simplified models were developed for the thermodynamic processes of the key ECS components in a commercial software program, ANSYS Simplorer. A computational fluid dynamics (CFD) program, ANSYS Fluent, was employed to simulate the thermal environment in a cabin. Through the coupling of Simplorer and Fluent, a PID Control method was applied to the aircraft ECS in Simplorer to achieve dynamic Control of the temperature of the supply air to the cabin, which was used as a Fluent input. The calculated supply air temperature agreed with the corresponding experimental data obtained from an MD-82 aircraft on the ground. The coupled model was then used to simulate a complete flight for the purpose of studying the interaction between ECS operation and the cabin thermal environment. The results show that the PID Controller in the ECS can maintain the cabin air temperature within ±0.6 K of the set point, with an acceptable air temperature distribution. The coupled models can be used for the design and analysis of the ECS and cabin thermal environment for commercial airplanes.

  • experimental study of particle deposition in the Environmental Control Systems of commercial airliners
    2016
    Co-Authors: Qing Cao, Daniel Wei, Xiong Shen, Chao-hsin Lin, Yudi Liu, Wei Liu, Steven L Baughcum, Sharon L Norris, Zhengwei Long
    Abstract:

    Abstract Serious air pollution and low on-time performance of commercial flights in China could result in more particles being deposited in the Environmental Control Systems (ECS) of the commercial airliners and ground air-conditioning carts (GAC). The particle deposited in the ECS and GAC could cause performance issues of the airplanes and GAC. In addition, particles penetrated to the aircraft cabin could cause adverse health impact on the passengers and crew. This investigation measured the PM 2.5 particle concentrations and the quantities of particles of different sizes at the inlet and outlet of the GAC and ECS in an MD-82 airplane parked next to Tianjin Airport under different air quality levels. The results showed that the deposition rate of the PM 2.5 mass in the GAC and ECS was 40–50%, with most (30–40%) of the deposition occurring in the ECS. For particles with a diameter of 5 μm or larger, the deposition rate was greater than 90%. For particles with a diameter of 0.5 μm or less, the deposition rate was less than 25% so they entered into the aircraft cabin. In addition, particle mass and number concentration was measured on commercial flights. The results indicated that particle concentrations were high compared with that during the cruising when the airplanes were on the ground at the Chinese airports where ambient particle concentrations were also high.