The Experts below are selected from a list of 135999 Experts worldwide ranked by ideXlab platform
Qingyan Chen - One of the best experts on this subject based on the ideXlab platform.
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predicting airflow distribution and contaminant transport in aircraft cabins with a simplified gasper model
Journal of Building Performance Simulation, 2016Co-Authors: Ruoyu You, Daniel Wei, Chao-hsin Lin, Jun Chen, Wei Liu, Qingyan ChenAbstract:This study investigated the air distribution and contaminant transport in aircraft cabins with gaspers by using computational fluid dynamics (CFD). If the detailed gasper geometry were used in the CFD simulations, the Grid Number would be unacceptably high. To reduce the Grid Number, this investigation proposed a method for simplifying the gasper geometry. The method was then validated by two sets of experimental data obtained from a cabin mockup and a real aircraft cabin. It was found that for the cabin mockup, the CFD simulation with the simplified gasper model reduced the Grid Number from 1.58 to 0.3 million and the computing cost from 2 days to 1 hour without compromising the accuracy. In the five-row economy-class cabin of the MD-82 airplane, the CFD simulation with the simplified gasper model was acceptable in predicting the distribution of air velocity, air temperature, and contaminant concentration.
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comparing the markov chain model with the eulerian and lagrangian models for indoor transient particle transport simulations
Aerosol Science and Technology, 2015Co-Authors: Chun Chen, Chao-hsin Lin, Wei Liu, Qingyan ChenAbstract:Correctly predicting transient particle transport in indoor environments is crucial to improving the design of ventilation systems and reducing the risk of acquiring airborne infectious diseases. Recently, a new model was developed on the basis of Markov chain frame for quickly predicting transient particle transport indoors. To evaluate this Markov chain model, this study compared it with the traditional Eulerian and Lagrangian models in terms of performance, computing cost, and robustness. Four cases of particle transport, three of which included experimental data, were used for this comparison. The Markov chain model was able to predict transient particle transport indoors with similar accuracy to the Eulerian and Lagrangian models. Furthermore, when the same time step size (Courant Number ≤1) and Grid Number were used for all three models, the Markov chain model had the highest calculation speed. The Eulerian model was faster than the Lagrangian model unless a super-fine Grid was used. This investigat...
Shijun You - One of the best experts on this subject based on the ideXlab platform.
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an alternative algorithm of tunnel piston effect by replacing three dimensional model with two dimensional model
Building and Environment, 2018Co-Authors: Minzhang Liu, Chunguang Zhu, Tong Cui, Huan Zhang, Wandong Zheng, Shijun YouAbstract:Abstract With the rapid development of the underground railways in China, the subway has become an increasingly important mode of transportation. Owing to the significant influence piston wind has on tunnel ventilation, piston wind has gained much attention from researchers. At present, the most common method for this research is a three-dimensional Computational Fluid Dynamics (CFD) simulation. However, the three-dimensional model has its inherent characteristics. Large Number of Grid quantities, long calculation times, significant computational requirements and high technical personnel requirements all influence the development of the three-dimensional model applied into the practical engineering. This study aimed to simplify the complicated three-dimensional model by creating a simple two-dimensional dynamic mesh model while ensuring the accuracy of the simplified simulation results. In order to explore suitable alternative methods, six types of two-dimensional simulation models are suggested in this study. Firstly, in order to prove the accuracy of the dynamic mesh simulation method, the CFD simulation results were validated with experimental results. Secondly, the six alternative methods were applied to the experimental model, full-scale model, train passing through a tunnel model, and subway station model in order to determine the best two-dimensional method. Finally, Grid Number, calculation time, and internal storage usage between the two-dimensional simulations and the three-dimensional simulation were evaluated, and these results demonstrated the superiority of the two-dimensional simulation model.
Minzhang Liu - One of the best experts on this subject based on the ideXlab platform.
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an alternative algorithm of tunnel piston effect by replacing three dimensional model with two dimensional model
Building and Environment, 2018Co-Authors: Minzhang Liu, Chunguang Zhu, Tong Cui, Huan Zhang, Wandong Zheng, Shijun YouAbstract:Abstract With the rapid development of the underground railways in China, the subway has become an increasingly important mode of transportation. Owing to the significant influence piston wind has on tunnel ventilation, piston wind has gained much attention from researchers. At present, the most common method for this research is a three-dimensional Computational Fluid Dynamics (CFD) simulation. However, the three-dimensional model has its inherent characteristics. Large Number of Grid quantities, long calculation times, significant computational requirements and high technical personnel requirements all influence the development of the three-dimensional model applied into the practical engineering. This study aimed to simplify the complicated three-dimensional model by creating a simple two-dimensional dynamic mesh model while ensuring the accuracy of the simplified simulation results. In order to explore suitable alternative methods, six types of two-dimensional simulation models are suggested in this study. Firstly, in order to prove the accuracy of the dynamic mesh simulation method, the CFD simulation results were validated with experimental results. Secondly, the six alternative methods were applied to the experimental model, full-scale model, train passing through a tunnel model, and subway station model in order to determine the best two-dimensional method. Finally, Grid Number, calculation time, and internal storage usage between the two-dimensional simulations and the three-dimensional simulation were evaluated, and these results demonstrated the superiority of the two-dimensional simulation model.
Wei Liu - One of the best experts on this subject based on the ideXlab platform.
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predicting airflow distribution and contaminant transport in aircraft cabins with a simplified gasper model
Journal of Building Performance Simulation, 2016Co-Authors: Ruoyu You, Daniel Wei, Chao-hsin Lin, Jun Chen, Wei Liu, Qingyan ChenAbstract:This study investigated the air distribution and contaminant transport in aircraft cabins with gaspers by using computational fluid dynamics (CFD). If the detailed gasper geometry were used in the CFD simulations, the Grid Number would be unacceptably high. To reduce the Grid Number, this investigation proposed a method for simplifying the gasper geometry. The method was then validated by two sets of experimental data obtained from a cabin mockup and a real aircraft cabin. It was found that for the cabin mockup, the CFD simulation with the simplified gasper model reduced the Grid Number from 1.58 to 0.3 million and the computing cost from 2 days to 1 hour without compromising the accuracy. In the five-row economy-class cabin of the MD-82 airplane, the CFD simulation with the simplified gasper model was acceptable in predicting the distribution of air velocity, air temperature, and contaminant concentration.
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comparing the markov chain model with the eulerian and lagrangian models for indoor transient particle transport simulations
Aerosol Science and Technology, 2015Co-Authors: Chun Chen, Chao-hsin Lin, Wei Liu, Qingyan ChenAbstract:Correctly predicting transient particle transport in indoor environments is crucial to improving the design of ventilation systems and reducing the risk of acquiring airborne infectious diseases. Recently, a new model was developed on the basis of Markov chain frame for quickly predicting transient particle transport indoors. To evaluate this Markov chain model, this study compared it with the traditional Eulerian and Lagrangian models in terms of performance, computing cost, and robustness. Four cases of particle transport, three of which included experimental data, were used for this comparison. The Markov chain model was able to predict transient particle transport indoors with similar accuracy to the Eulerian and Lagrangian models. Furthermore, when the same time step size (Courant Number ≤1) and Grid Number were used for all three models, the Markov chain model had the highest calculation speed. The Eulerian model was faster than the Lagrangian model unless a super-fine Grid was used. This investigat...
Chao-hsin Lin - One of the best experts on this subject based on the ideXlab platform.
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predicting airflow distribution and contaminant transport in aircraft cabins with a simplified gasper model
Journal of Building Performance Simulation, 2016Co-Authors: Ruoyu You, Daniel Wei, Chao-hsin Lin, Jun Chen, Wei Liu, Qingyan ChenAbstract:This study investigated the air distribution and contaminant transport in aircraft cabins with gaspers by using computational fluid dynamics (CFD). If the detailed gasper geometry were used in the CFD simulations, the Grid Number would be unacceptably high. To reduce the Grid Number, this investigation proposed a method for simplifying the gasper geometry. The method was then validated by two sets of experimental data obtained from a cabin mockup and a real aircraft cabin. It was found that for the cabin mockup, the CFD simulation with the simplified gasper model reduced the Grid Number from 1.58 to 0.3 million and the computing cost from 2 days to 1 hour without compromising the accuracy. In the five-row economy-class cabin of the MD-82 airplane, the CFD simulation with the simplified gasper model was acceptable in predicting the distribution of air velocity, air temperature, and contaminant concentration.
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comparing the markov chain model with the eulerian and lagrangian models for indoor transient particle transport simulations
Aerosol Science and Technology, 2015Co-Authors: Chun Chen, Chao-hsin Lin, Wei Liu, Qingyan ChenAbstract:Correctly predicting transient particle transport in indoor environments is crucial to improving the design of ventilation systems and reducing the risk of acquiring airborne infectious diseases. Recently, a new model was developed on the basis of Markov chain frame for quickly predicting transient particle transport indoors. To evaluate this Markov chain model, this study compared it with the traditional Eulerian and Lagrangian models in terms of performance, computing cost, and robustness. Four cases of particle transport, three of which included experimental data, were used for this comparison. The Markov chain model was able to predict transient particle transport indoors with similar accuracy to the Eulerian and Lagrangian models. Furthermore, when the same time step size (Courant Number ≤1) and Grid Number were used for all three models, the Markov chain model had the highest calculation speed. The Eulerian model was faster than the Lagrangian model unless a super-fine Grid was used. This investigat...
