The Experts below are selected from a list of 138 Experts worldwide ranked by ideXlab platform
Jiawei Zhou - One of the best experts on this subject based on the ideXlab platform.
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Efficiency and stability of lump coal particles swirling flow pneumatic Conveying system
Chemical Engineering Research and Design, 2020Co-Authors: Jiawei Zhou, Xiaoming Han, Shuangxi Jing, Yu LiuAbstract:Abstract To clear the swirling flow pneumatic Conveying Performance for blocky fuel particles, particularly for lump coal particles, a side inlet guide vane swirling generator was developed and employed to study the efficiency and stability of lump coal particles in swirling flow pneumatic Conveying. In total, 32 pilot scale tests for different conditions, including different airflow rates, solid mass flow rates, and swirling intensities, were conducted in this paper. The efficiency and stability of lump coal particles in swirling flow pneumatic Conveying are thoroughly discussed by considering the static pressure loss and pressure fluctuation standard deviation. The pressure characteristics for different Conveying stages and frequency spectrum constituents of the static pressure are also discussed. The results show that the swirling flow has better energy preservation characteristics and Conveying Performance in proper conditions. Four main factors contribute to the static pressure fluctuation in three different frequency bands. The results also show that a low mean gas velocity with a medium swirling intensity and a high mean gas velocity with a weak swirling intensity can improve the Conveying stability. The swirling flow is more stable at the front of the pipeline; meanwhile, the axial flow is better in the second half.
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Prediction of lump coal particle pickup velocity in pneumatic Conveying
Powder Technology, 2019Co-Authors: Jiawei ZhouAbstract:Abstract To reduce the airflow velocity and improve the pneumatic Conveying Performance of lump coal particle, the pickup process and pickup prediction of lump coal particles with 5–15 mm diameters are firstly studied in this paper. The pickup velocity of lump coal particles were determined by the weight loss method and observed by a high speed camera. The results show that the pickup mechanism, the pickup process, and the variation in the weight loss curve of the lump coal particle are similar to the results of Geldart D particles and Geldart B particles. Notably, two observations are worth highlighting: (1) the pickup of lump coal particles is determined by the critical motion, namely, initial shaking and rolling, which are mainly affected by the disturbance of airflow, the disturbance of particle impact, and the disturbance of unstable-support; and (2) the K & R model has a favorable adaptability to large lump coal particles, and an exponential equation, based on the foundation of the K & R model and taking the dimensionless particle size into account, is employed to predict the pickup velocity of lump coal particles. The prediction deviations agree well with the experimental results.
Yu Liu - One of the best experts on this subject based on the ideXlab platform.
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Efficiency and stability of lump coal particles swirling flow pneumatic Conveying system
Chemical Engineering Research and Design, 2020Co-Authors: Jiawei Zhou, Xiaoming Han, Shuangxi Jing, Yu LiuAbstract:Abstract To clear the swirling flow pneumatic Conveying Performance for blocky fuel particles, particularly for lump coal particles, a side inlet guide vane swirling generator was developed and employed to study the efficiency and stability of lump coal particles in swirling flow pneumatic Conveying. In total, 32 pilot scale tests for different conditions, including different airflow rates, solid mass flow rates, and swirling intensities, were conducted in this paper. The efficiency and stability of lump coal particles in swirling flow pneumatic Conveying are thoroughly discussed by considering the static pressure loss and pressure fluctuation standard deviation. The pressure characteristics for different Conveying stages and frequency spectrum constituents of the static pressure are also discussed. The results show that the swirling flow has better energy preservation characteristics and Conveying Performance in proper conditions. Four main factors contribute to the static pressure fluctuation in three different frequency bands. The results also show that a low mean gas velocity with a medium swirling intensity and a high mean gas velocity with a weak swirling intensity can improve the Conveying stability. The swirling flow is more stable at the front of the pipeline; meanwhile, the axial flow is better in the second half.
Pw Wypych - One of the best experts on this subject based on the ideXlab platform.
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Effect of Rotary Valve Leakage on Pneumatic Conveying Performance
Particulate Science and Technology, 2008Co-Authors: Pw WypychAbstract:A new theoretical air leakage model was developed for both conventional and high-pressure rotary valves. Different sizes of rotary valves (D = 250 and 300 mm) and a single-slit apparatus were tested over a wide range of conditions (N = 0 to 30 rpm; Δp v = 0 to 300 kPa; c = 0.10 to 0.25 mm). All the model predictions were found to be within ±6% of the experimental data. This was a dramatic improvement compared with all previous models and even suppliers' curves, where errors were found to be between − 48% and + 39%. A new centrifugal vent hopper also was developed to maximize the removal of air leakage and, hence, feed rate capacity. Based on data from three products (130 µm Poly Powder, fibrous perlite, and 10 µm ground powder), the new vent hopper was found to increase feed rate and Conveying capacity by at least a factor of two.
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Mechanism for Unstable Pneumatic Conveying of Granular Materials through Horizontal Pipe
2001Co-Authors: Pw Wypych, David B HastieAbstract:Since the pneumatic Conveying Performance of granular materials in the transition zone between dilutephase and dense-phase still lacks full understanding and assessment, especially the mechanism for the formation of unstable flow, tests have been carried out on poly pellets (particle diameter = 4.7 mm, particle density = 897 kg/m) and two different stainless steel pipelines (60.3 and 98.4 mm ID, each 21 m long). By careful observation and analysis of flow behaviours (covering dilute-phase, unstable zone and low-velocity slugflow), five different flow modes (as the air velocity is decreased): fully suspended flow; strand flow; stable or unstable strand flow over a stationary layer for low solid mass flow rates; strand flow over a slowly moving bed for high solid mass flow rates; low-velocity slug-flow are identified. The mechanism involved in the formation of unstable zone was explored.
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Low-velocity pneumatic Conveying of powders
1995Co-Authors: B. Mi, Pw WypychAbstract:Most studies into low-velocity pneumatic Conveying are confined to the transportation of coarse granular materials that display natural slugging ability. However, some powders also exhibit natural slugging tendency and can be good candidates for low-velocity pneumatic Conveying. This paper studies the Conveying characteristics of a semolina powder over a broad range of operating conditions. From this study it is found that the low-velocity pneumatic Conveying Performance of powders is quite different to coarse granular materials. The most significant effect appears to be slug velocity. Based on experimental results, a model for predicting pipeline pressure drop in low-velocity pneumatic Conveying of powders is obtained by modifying a model that was developed previously for coarse granular materials. The results predicted by the modified model agree well with the experimental data.
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Low-velocity Pneumatic Conveying of Fine Powders
1995Co-Authors: B. Mi, Pw WypychAbstract:Most studies into low-velocity pneumatic Conveying are confined to the transportation of coarse granular materials that display natural slugging ability. However, some fine powders, such as semolina, also exhibit natural slugging tendency and can be good candidates for low-velocity pneumatic Conveying. This paper studies the Conveying characteristics of fine powders by Conveying semolina over a broad range of operating conditions. From this study it is found that the low-velocity pneumatic Conveying Performance of fine powder is quite different to coarse granular materials. The most significant effect appears to be slug velocity. Based on experimental results, a model for predicting pipeline pressure drop in low-velocity pneumatic Conveying of fine powders is obtained by modifying a model that was developed previously for coarse granular materials. The results predicted by the modified model agree well with the experimental data.
Xiaoming Han - One of the best experts on this subject based on the ideXlab platform.
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Efficiency and stability of lump coal particles swirling flow pneumatic Conveying system
Chemical Engineering Research and Design, 2020Co-Authors: Jiawei Zhou, Xiaoming Han, Shuangxi Jing, Yu LiuAbstract:Abstract To clear the swirling flow pneumatic Conveying Performance for blocky fuel particles, particularly for lump coal particles, a side inlet guide vane swirling generator was developed and employed to study the efficiency and stability of lump coal particles in swirling flow pneumatic Conveying. In total, 32 pilot scale tests for different conditions, including different airflow rates, solid mass flow rates, and swirling intensities, were conducted in this paper. The efficiency and stability of lump coal particles in swirling flow pneumatic Conveying are thoroughly discussed by considering the static pressure loss and pressure fluctuation standard deviation. The pressure characteristics for different Conveying stages and frequency spectrum constituents of the static pressure are also discussed. The results show that the swirling flow has better energy preservation characteristics and Conveying Performance in proper conditions. Four main factors contribute to the static pressure fluctuation in three different frequency bands. The results also show that a low mean gas velocity with a medium swirling intensity and a high mean gas velocity with a weak swirling intensity can improve the Conveying stability. The swirling flow is more stable at the front of the pipeline; meanwhile, the axial flow is better in the second half.
Shuangxi Jing - One of the best experts on this subject based on the ideXlab platform.
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Efficiency and stability of lump coal particles swirling flow pneumatic Conveying system
Chemical Engineering Research and Design, 2020Co-Authors: Jiawei Zhou, Xiaoming Han, Shuangxi Jing, Yu LiuAbstract:Abstract To clear the swirling flow pneumatic Conveying Performance for blocky fuel particles, particularly for lump coal particles, a side inlet guide vane swirling generator was developed and employed to study the efficiency and stability of lump coal particles in swirling flow pneumatic Conveying. In total, 32 pilot scale tests for different conditions, including different airflow rates, solid mass flow rates, and swirling intensities, were conducted in this paper. The efficiency and stability of lump coal particles in swirling flow pneumatic Conveying are thoroughly discussed by considering the static pressure loss and pressure fluctuation standard deviation. The pressure characteristics for different Conveying stages and frequency spectrum constituents of the static pressure are also discussed. The results show that the swirling flow has better energy preservation characteristics and Conveying Performance in proper conditions. Four main factors contribute to the static pressure fluctuation in three different frequency bands. The results also show that a low mean gas velocity with a medium swirling intensity and a high mean gas velocity with a weak swirling intensity can improve the Conveying stability. The swirling flow is more stable at the front of the pipeline; meanwhile, the axial flow is better in the second half.