{"title":"固体-气体锥形喷嘴床聚合物热解研究:CFD 模拟","authors":"Sobhan Jafari, Hadi Soltani, M. Gholizadeh","doi":"10.1515/ijcre-2023-0209","DOIUrl":null,"url":null,"abstract":"\n The hydrodynamics of a conical spouted bed was simulated utilizing the Eulerian–Eulerian Two-Fluid Model (TFM) incorporating a kinetic theory of granular flows. The simulations were confirmed with experimental data. To accurately examine the pyrolysis process, the hydrodynamics of the solid bed as well as the heat transfer inside it were analysed separately by considering a precise synthetic model. The effects of gas velocity, particle size, bed length, and temperature were thoroughly investigated. The results indicated that the amount of relative standard deviation increases with an increase in the inlet velocity into the bed. This amount of deviation at the inlet velocity (0.6 m/s for tar and gas flow to its maximum value of 9.1 and 9.4) is not desirable in product production and should be modified so that the amount of gas flow increases and the tar produced reaches the minimum possible amount. Also, the graphs of the relative standard deviation in terms of temperature indicate that the increase in temperature from 730 to 950 K is associated with a relatively smaller fluctuation of the relative standard deviation so that at the temperature of 730 K, it is 7.2 % for tar and 6.4 % for gas flow, while at temperature of 950 K, it is 6.5 % for wire and 6.8 % for gas flow. Finally, the results determined that small-diameter particles have a more significant fountain height and also higher velocity in the spout section.","PeriodicalId":51069,"journal":{"name":"International Journal of Chemical Reactor Engineering","volume":null,"pages":null},"PeriodicalIF":1.6000,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Investigation of polymers pyrolysis in a solid-gas conical spouted bed: CFD simulation\",\"authors\":\"Sobhan Jafari, Hadi Soltani, M. Gholizadeh\",\"doi\":\"10.1515/ijcre-2023-0209\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"\\n The hydrodynamics of a conical spouted bed was simulated utilizing the Eulerian–Eulerian Two-Fluid Model (TFM) incorporating a kinetic theory of granular flows. The simulations were confirmed with experimental data. To accurately examine the pyrolysis process, the hydrodynamics of the solid bed as well as the heat transfer inside it were analysed separately by considering a precise synthetic model. The effects of gas velocity, particle size, bed length, and temperature were thoroughly investigated. The results indicated that the amount of relative standard deviation increases with an increase in the inlet velocity into the bed. This amount of deviation at the inlet velocity (0.6 m/s for tar and gas flow to its maximum value of 9.1 and 9.4) is not desirable in product production and should be modified so that the amount of gas flow increases and the tar produced reaches the minimum possible amount. Also, the graphs of the relative standard deviation in terms of temperature indicate that the increase in temperature from 730 to 950 K is associated with a relatively smaller fluctuation of the relative standard deviation so that at the temperature of 730 K, it is 7.2 % for tar and 6.4 % for gas flow, while at temperature of 950 K, it is 6.5 % for wire and 6.8 % for gas flow. Finally, the results determined that small-diameter particles have a more significant fountain height and also higher velocity in the spout section.\",\"PeriodicalId\":51069,\"journal\":{\"name\":\"International Journal of Chemical Reactor Engineering\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.6000,\"publicationDate\":\"2024-04-03\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"International Journal of Chemical Reactor Engineering\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://doi.org/10.1515/ijcre-2023-0209\",\"RegionNum\":4,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"Chemical Engineering\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Chemical Reactor Engineering","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1515/ijcre-2023-0209","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"Chemical Engineering","Score":null,"Total":0}
引用次数: 0
摘要
利用包含颗粒流动动力学理论的欧拉-欧拉双流体模型(TFM)模拟了锥形喷流床的流体力学。模拟结果得到了实验数据的证实。为了准确检验热解过程,通过考虑一个精确的合成模型,分别分析了固体床的流体力学及其内部的热传导。对气体速度、颗粒大小、床层长度和温度的影响进行了深入研究。结果表明,相对标准偏差量随着床层入口速度的增加而增加。这种入口速度下的偏差量(焦油和气体流量为 0.6 m/s,最大值分别为 9.1 和 9.4)在产品生产中是不可取的,应加以修改,使气体流量增加,焦油产量达到最小值。此外,与温度有关的相对标准偏差图显示,温度从 730 K 升至 950 K 时,相对标准偏差的波动相对较小,因此在温度为 730 K 时,焦油的相对标准偏差为 7.2%,气体流量的相对标准偏差为 6.4%;而在温度为 950 K 时,金属丝的相对标准偏差为 6.5%,气体流量的相对标准偏差为 6.8%。最后,研究结果表明,小直径颗粒的喷泉高度更大,在喷口部分的速度也更高。
Investigation of polymers pyrolysis in a solid-gas conical spouted bed: CFD simulation
The hydrodynamics of a conical spouted bed was simulated utilizing the Eulerian–Eulerian Two-Fluid Model (TFM) incorporating a kinetic theory of granular flows. The simulations were confirmed with experimental data. To accurately examine the pyrolysis process, the hydrodynamics of the solid bed as well as the heat transfer inside it were analysed separately by considering a precise synthetic model. The effects of gas velocity, particle size, bed length, and temperature were thoroughly investigated. The results indicated that the amount of relative standard deviation increases with an increase in the inlet velocity into the bed. This amount of deviation at the inlet velocity (0.6 m/s for tar and gas flow to its maximum value of 9.1 and 9.4) is not desirable in product production and should be modified so that the amount of gas flow increases and the tar produced reaches the minimum possible amount. Also, the graphs of the relative standard deviation in terms of temperature indicate that the increase in temperature from 730 to 950 K is associated with a relatively smaller fluctuation of the relative standard deviation so that at the temperature of 730 K, it is 7.2 % for tar and 6.4 % for gas flow, while at temperature of 950 K, it is 6.5 % for wire and 6.8 % for gas flow. Finally, the results determined that small-diameter particles have a more significant fountain height and also higher velocity in the spout section.
期刊介绍:
The International Journal of Chemical Reactor Engineering covers the broad fields of theoretical and applied reactor engineering. The IJCRE covers topics drawn from the substantial areas of overlap between catalysis, reaction and reactor engineering. The journal is presently edited by Hugo de Lasa and Charles Xu, counting with an impressive list of Editorial Board leading specialists in chemical reactor engineering. Authors include notable international professors and R&D industry leaders.