超声蒸发器传热性能数值模拟

发布时间：2018-04-27 12:48

  本文选题：超声蒸发器 + 回归分析　； 参考：《天津科技大学》2016年硕士论文

【摘要】：化工工艺生产过程中，有效地提氋传热强度，节约能源的消耗以及降低生产的运行成本等是其重点关注的问题。而传统的蒸发设备中高耗能、低产率的问题还是普遍存在的。如何对其进行优化改进成了目前化工生产中亟待解决的问题。本文把超声波技术应用到蒸发单元操作中，结合超声波技术和蒸发技术的各自特点，设计出新型的蒸发操作装置，合理优化蒸发操作工艺，对其传热性能方面进行了实验研究和数值模拟分析。本文使用课题组设计制造的超声蒸发装置，进行了纯水的强化传热实验，并结合实验进行了超声蒸发器加热室内流场和温度场的数值模拟，对指导超声蒸发器的工艺优化和技术改进提供参考。得出如下结论：1)本文选取固定效应模型，分别对进料量、蒸发温度、功率密度等参数进行了单因素实验分析，并结合实验数据进行了单因素的回归模型的建立，通过验证性实验表明回归模型的准确性，可用来预测单因素条件下的传热系数。单因素实验条件下最佳操作参数点分别为进料量40 L/h，，蒸发温度70℃，功率密度0.8A。2)实验设计中采用均匀设计，分析双因素对传热系数的影响，建立双因素条件下最佳实验操作参数，并建立了传热系数与操作参数的回归方程，提出此回归方程在实验条件下的适用性。采用实验设计的最佳操作参数范围是进料量30L/h-55L/h，蒸发温度70℃-90℃，功率密度0A-1.2A。3)利用FLUENT软件进行超声蒸发器加热室内的传热性能的数值模拟，模拟了管内沸腾情况下的流场和温度场，形象地表征了管内沸腾的超声空化状态，对管内壁面剪切力和出口管板进行分析，得出管内循环时剧烈湍动而使得核态沸腾持续进行，对实验的强化传热结果得以验证，该结果对指导超声蒸发器的工艺改进和优化设计具有重要的参考价值。
[Abstract]:In the process of chemical process, it is important to raise heat transfer intensity effectively, to save energy consumption and to reduce production cost. However, the problem of high energy consumption and low yield in traditional evaporating equipment is widespread. How to optimize and improve it has become an urgent problem in chemical production. In this paper, ultrasonic technology is applied to evaporative unit operation. Combined with the respective characteristics of ultrasonic technology and evaporation technology, a new type of evaporation operation device is designed, and the evaporation operation technology is optimized reasonably. Experimental study and numerical simulation are carried out on the heat transfer performance. In this paper, the experiments of enhanced heat transfer of pure water are carried out by using the ultrasonic evaporator designed and manufactured by the research group, and the numerical simulation of the flow field and temperature field in the heating chamber of the ultrasonic evaporator is carried out in combination with the experiment. It provides a reference for guiding the process optimization and technical improvement of ultrasonic evaporator. The following conclusions are drawn as follows: (1) in this paper, the fixed effect model is selected, and the parameters such as feed quantity, evaporation temperature and power density are analyzed by single factor experiment, and the regression model of single factor is established by combining the experimental data. The verificative experiments show that the regression model is accurate and can be used to predict the heat transfer coefficient under the condition of single factor. The optimum operating parameters under single factor experimental conditions are as follows: feed quantity 40 L / h, evaporation temperature 70 鈩

本文编号：1810791