Gas-Liquid Interfaces: Turbulence and Scalar Exchange

建议没有。当前位置主要研究者：S. banerjee机构：加州大学圣巴巴拉加分校-液体界面：湍流和标量交换气液界面的湍流输运过程仍然知之甚少，尽管它是许多工业和环境过程的核心——例如，对海洋温室气体吸收的可靠估计。这种贫乏的知识主要来自于对接近运动、变形和断裂界面的速度、温度和浓度场进行测量和数值模拟的困难。因此，人们对移动界面附近的湍流结构和输运过程的了解要比固体边界附近的少得多，尽管在化学和电力工业中，许多净化、反应和能量转移过程都是在这样的界面上进行的。该项目的目标是利用基于数字粒子成像测速（DPIV）和直接数值模拟（DNS）在复杂边界上的最新进展的实验和计算方法的结合，促进对这些问题的理解。特别是，将研究由风切变、破波、热对流、壁面切变和组合等多种来源引起的液侧近界面湍流的结构和影响。所提出的实验和模拟将在广泛的条件下提供高质量的数据，这将对理解机制和评估建模方法具有持久的价值。此外，结果将用于评估有关湍流传输过程的广泛影响假设，如果证明有效，将构成对该主题的基本理解的重大进展。这个项目的广泛影响在于它有可能降低多相处理设备的设计和扩大规模的成本，例如冷凝器、蒸发器、气体吸收器、洗涤器和气液反应器，以及在一些环境应用中。其中包括大气与海洋或河流系统之间的碳交换，汞和多氯联苯等挥发性有毒物质的命运和运输，以及缺氧水域的曝气。通过更好地为有关温室气体排放等问题的政策提供信息，其广泛的社会影响将非常显著。拟议工作的另一个影响是，它有可能在一个跨学科领域教育研究人员，在这个领域中，环境考虑和工程方法都很重要——这是解决未来社会需求的重要背景。

PROPOSAL NO.: CTS-0553333PRINCIPAL INVESTIGATOR: S. BANERJEEINSTITUTION: UNIVERSITY OF CALIFORNIA - SANTA BARBARAGAS-LIQUID INTERFACES: TURBULENCE AND SCALAR EXCHANGE Turbulent transport processes at gas-liquid interfaces remain poorly understood despite being central to many industrial and environmental processes- for example, to reliable estimation of greenhouse gas uptake by the oceans. This poor state of knowledge derives primarily from the difficulty of making measurements and doing numerical simulations of velocity, temperature and concentration fields close to moving, deforming and breaking interfaces. As a result much less is known about turbulence structure and transport processes near mobile interfaces than near solid boundaries, even though many purification, reaction and energy transfer processes are conducted across such interfaces in the chemical and power industries. The objective of this project is to contribute to improving the state of understanding of such problems using a combination of experimental and computational approaches based n recent advances in digital particle imaging velocimetry (DPIV) and direct numerical simulation (DNS) over complex boundaries. In particular, the structure and effects of liquid-side, near-interface turbulence, originating from a variety of sources such as wind shear, wave breaking, thermal convection, wall shear and combinations, will be studied. The proposed experiments and simulations will provide high quality data over a wide range of conditions that will be of lasting value in understanding mechanisms and evaluating modeling approaches. Also the results will be used to assess broad reaching hypotheses regarding turbulent transport processes that if proved valid, would constitute a significant advance in fundamental understanding of the subject. The broad impact of this project arises from its potential to reduce costs for design and scale-up of multiphase-processing equipment, such as condensers, evaporators, gas absorbers, scrubbers and gas-liquid reactors, as well in several environmental applications. These include exchange of carbon between the atmosphere and ocean or river systems, fate and transport of volatile toxics like mercury and PCBs, and the aeration of hypoxic waters. The broad societal impact by better informing policy regarding matters such as greenhouse gas emissions would be very significant. Another impact of the proposed work is its potential to educate researchers in an interdisciplinary area in which both environmental considerations and engineering approaches are important- a background of importance in addressing future societal needs.