• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>AIChE Journal >Microwave Assisted Flow Synthesis: Coupling of Electromagnetic and Hydrodynamic Phenomena
【24h】

Microwave Assisted Flow Synthesis: Coupling of Electromagnetic and Hydrodynamic Phenomena

机译：微波辅助流动合成：电磁和流体动力现象的耦合

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

This article describes the results of a modeling study performed to understand the microwave heating process in continuous-flow reactors. It demonstrates the influence of liquid velocity profiles on temperature and microwave energy dissipation in a microwave integrated milli reactor-heat exchanger. Horizontal cocurrent flow of a strong microwave absorbing reaction mixture (ethanol + acetic acid, molar ratio 5:1) and a microwave transparent coolant (toluene) was established in a Teflon supported quartz tube (i.d.: 3 × 10~(-3) m and o.d.: 4 × 10~(-3) m) and shell (i.d.: 7 × 10~(-3) m and o.d.: 9 × 10~(-3) m), respectively. Modeling showed that the temperature rise of the highly microwave absorbing reaction mixture was up to four times higher in the almost stagnant liquid at the reactor walls than in the bulk liquid. The coolant flow was ineffective in controlling the outlet reaction mixture temperature. However, at high flow rates it limits the overheating of the stagnant liquid film of the reaction mixture at the reactor walls. It was also found that the stagnant layer around a fiber optic temperature probe, when inserted from the direction of the flow, resulted in much higher temperatures than the bulk liquid. This was not the case when the probe was inserted from the opposite direction. The experimental validations of these modeling results proved that the temperature profiles depend more on the reaction mixture velocity profiles than on the microwave energy dissipation/electric field intensity. Thus, in flow synthesis, particularly where a focused microwave field is applied over a small tubular flow reactor, it is very important to understand the large (direct/indirect) influence of reactor internals on the microwave heating process.
机译：本文介绍了进行建模研究的结果，以了解连续流反应器中的微波加热过程。它证明了微波集成毫波反应器-热交换器中液体速度分布对温度和微波能量耗散的影响。在特氟龙支撑的石英管（id：3×10〜（-3）m）中建立强微波吸收反应混合物（乙醇+乙酸，摩尔比5：1）和微波透明冷却剂（甲苯）的水平并流。和od：4×10〜（-3）m）和壳（id：7×10〜（-3）m和od：9×10〜（-3）m）。模型表明，在反应器壁处几乎停滞的液体中，高度吸收微波的反应混合物的温度升高比在本体液体中的温度升高高四倍。冷却剂流在控制出口反应混合物温度方面无效。然而，在高流速下，它限制了反应混合物在反应器壁处停滞的液膜的过热。还发现，当从流动方向插入时，光纤温度探头周围的停滞层会导致温度比散装液体高得多。从相反方向插入探针时，情况并非如此。这些建模结果的实验​​验证证明，温度分布更多地取决于反应混合物的速度分布，而不是微波能量耗散/电场强度。因此，在流动合成中，尤其是在小型管状流动反应器上施加聚焦微波场的情况下，了解反应器内部对微波加热过程的巨大（直接/间接）影响非常重要。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号