Atomization of High Viscosity and Suspension Fluids

高粘度和悬浮液的雾化

• 批准号: 250458-2012
• 负责人: Ashgriz, Nasser
• 金额: $ 2.26万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=570923
• 关键词: Atomization; Viscosity; Suspension; Fluids

In Canada's oil sands, bitumen is mixed with steam and the mixture is sprayed into a coker to upgrade bitumen to synthetic crude oil. The spray characteristics is one of the determining factors in the efficiently of this process. However, due to the complexity of this fluid (bitumen-steam mixture), there is very limited information on the spray characteristics of these sprays. The available studies on this type of systems, have replaced this complex mixtures with water and air mixtures or some oil and air mixtures. Bitumen-steam mixture is a highly viscous fluid with large percentage of suspended solid particles, and it is too simplistic to model it with mixture of water-air. The objective of the present proposed research is to characterize sprays of high viscosity fluids with suspended particles, in general, and actual bitumen-steam mixtures, as well as coal slurries, in particular. In order to achieve this objective the following tasks will be pursued. (1) Develop an atomization and spray model to predict the spray formation of heavy oils and liquids with suspensions from typical nozzles used in Canadian oil sands. (2) Conduct experimental spray testing on nozzles used in Canadian oil sands using actual fluids, such as bitumen and heavy oils with suspensions. (3) Use the atomization model developed here to predict spray characters from the Canadian oil sands with actual fluids. Use the experimental data to fine tune the spray model. (4) Use the validated spray code to predict the spray characteristics of large scale nozzles. (5) Perform parametric studies to improve nozzle performance both in terms of spray droplet sizes and also reducing wear and tear of the nozzle. The present research is also aimed at addressing the following questions: (i) In a highly turbulent jet, what triggers the gas-liquid interface instability and how does this instability grow resulting in the formation of ligaments and droplets. (ii) How does the liquid viscosity affect the breakup of liquid masses from an interface? (iii) How the existences of suspended particles effect the atomization process?

在加拿大的油砂中，沥青与蒸汽混合，然后将混合物喷入焦化装置，将沥青升级为合成原油。喷雾特性是影响该工艺效率的决定性因素之一。 然而，由于这种流体（沥青蒸汽混合物）的复杂性，关于这些喷雾的喷雾特性的信息非常有限。 对这种类型的系统的现有研究已经用水和空气混合物或一些油和空气混合物取代了这种复杂的混合物。沥青-蒸汽混合物是一种含有大量悬浮固体颗粒的高粘性流体，用水-空气混合物来模拟它过于简单。 目前提出的研究的目的是表征喷雾的高粘度流体与悬浮颗粒，在一般情况下，和实际的沥青蒸汽混合物，以及煤浆，特别是。为实现这一目标，将开展以下工作。(1)开发一个雾化和喷雾模型，以预测加拿大油砂中使用的典型喷嘴的重油和液体的喷雾形成。(2)对加拿大油砂中使用的喷嘴进行实验性喷雾测试，使用实际流体，如沥青和重油悬浮液。(3)用本文建立的雾化模型预测了加拿大油砂的喷雾特性。利用实验数据对喷雾模型进行微调。(4)用验证过的喷雾程序预测大型喷嘴的喷雾特性。 (5)执行参数研究，以提高喷嘴性能，包括喷雾液滴尺寸和减少喷嘴磨损。 本研究还旨在解决以下问题：（i）在高度湍流射流中，是什么触发了气液界面不稳定性，以及这种不稳定性如何增长，导致韧带和液滴的形成。(ii)液体粘度如何影响液体质量在界面上的破碎？(iii)悬浮颗粒的存在对雾化过程有何影响？