Investigation of continuous-flow mixing of non-newtonian fluids through tomography, ultrasonic velocimetry and computational fluid dynamics techniques

通过断层扫描、超声测速和计算流体动力学技术研究非牛顿流体的连续流动混合

• 批准号: 311795-2009
• 负责人: EinMozaffari, Farhad
• 金额: $ 2.19万
• 依托单位: Ryerson University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=496819
• 关键词: Investigation; continuous; flow; mixing; non

Continuous-flow mixing of non-Newtonian fluids is a vital component to many processes including polymerization, fermentation, waste water treatment, and pulp and paper manufacturing because of its demonstrated ability to improve product uniformity and minimize shut down, loading and unloading times. The current design of continuous mixing of non-Newtonian fluids is based on limited published information, and trial and error methods. The assumption of ideal mixing has traditionally been used to design these mixing processes. However, the complex rheology displayed by non-Newtonian fluids can create considerable deviation from ideal mixing. Studies show that the non-ideal flow such as short circuiting, recirculation, and dead zones significantly affect the performance of continuous mixing processes. In fact, a thorough search of the literature suggests that our current understanding and implementation of continuous mixing of non-Newtonian fluids is insufficient to ensure good mixing. In particular, design criteria incorporating mixing dynamics are needed so that acceptable mixing responses can be attained from continuous mixing systems. Thus, the long term research program goal is to develop methodology and tools to design continuous mixing systems for fluids with complex rheology through advanced flow visualization techniques (e.g. tomography and ultrasonic velocimetry), and advanced computational fluid dynamics methods. The work is of great importance to the chemical industry of Canada. The annual loss due to poor mixing is estimated at $10 billion in the North America chemical industry alone [Handbook of Industrial Mixing]. The proposed experimental and modeling research program will improve our understanding of continuous mixing of non-Newtonian fluids and answer some of the fundamental questions about the design criteria. Applying the finding of this study will improve variability reduction in the continuous mixing processes. This will lead to capital cost savings, chemical cost reduction, improved quality of products, and more efficient use of power. The proposed research will contribute to the training of highly qualified personnel by actively involving Ph.D. and master's students.

非牛顿流体的连续流动混合是许多过程的重要组成部分，包括聚合、发酵、废水处理以及纸浆和造纸，因为其被证明能够提高产品均匀性并最大限度地减少停机、装载和卸载时间。非牛顿流体连续混合的当前设计是基于有限的公开信息和试错法。理想混合的假设传统上被用于设计这些混合过程。然而，非牛顿流体所表现出的复杂流变学可能会产生与理想混合的相当大的偏差。研究表明，短路、回流、死区等非理想流动对连续混合过程的性能有着重要的影响。事实上，对文献的彻底搜索表明，我们目前对非牛顿流体连续混合的理解和实施不足以确保良好的混合。特别是，需要结合混合动力学的设计标准，以便可以从连续混合系统获得可接受的混合响应。因此，长期研究计划的目标是开发方法和工具，通过先进的流动可视化技术（如断层扫描和超声波测速）和先进的计算流体动力学方法，为具有复杂流变性的流体设计连续混合系统。这项工作对加拿大的化学工业具有重要意义。据估计，仅在北美化学工业中，每年因混合不良而造成的损失就达100亿美元[工业混合手册]。拟议的实验和建模研究计划将提高我们对非牛顿流体连续混合的理解，并回答有关设计标准的一些基本问题。应用本研究的发现将改善连续混合过程中的变异性降低。这将导致资本成本节约、化学品成本降低、产品质量提高以及更有效地使用电力。拟议的研究将有助于培养高素质的人才，积极参与博士。和硕士生。