Turbulant Convection in a Fluid Heater from Below

流体加热器中的湍流对流从下方

• 批准号: 0702111
• 负责人: Guenter Ahlers
• 金额: $ 77.5万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-05-01 至 2013-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0702111&HistoricalAwards=false
• 关键词: Turbulant; Convection; Fluid; Heater; Below

Non-Technical Abstract:Turbulent convection in a fluid heated from below occurs naturally in Earth's atmosphere and oceans where it influences climate and weather, in Earth's mantle where it contributes to the motion of continental plates, in Earth's outer core where it determines the magnetic field, in the Sun where it influences the temperature on Earth, and in many industrial processes where it may have significant economic consequences. This grant will support experiments under highly controlled laboratory conditions and in samples of idealized shapes where some of the central physical components of this process can be studied quantitatively. These components include relatively quiet fluid layers just above the bottom and below the top plate (the "boundary layers"), and a turbulent interior with highly fluctuating temperature and fluid-flow. A large convection cell, known as the "wind of turbulence", is superimposed on these interior fluctuations. Quantitative measurements will be made of the turbulent enhancement of the heat transport, of the temperature distribution in the interior, and of the wind dynamics. The highly quantitative experiments are of modest complexity and thus afford an exceptional diverse learning experience for both graduate and undergraduate students who participate in the work.Technical Abstract:Turbulent convection in a fluid heated from below occurs in many geophysical, astrophysical, and industrial situations. This grant will support experiments under highly controlled laboratory conditions and in samples of idealized, mostly cylindrical, shapes where some of the central physical components of this process can be studied quantitatively. These components include top and bottom boundary layers, and a turbulent interior with highly fluctuating temperature and velocity fields. A large-scale flow (LSC) is superimposed on the interior fluctuations. Quantitative measurements of heat transport will be made at the largest possible Rayleigh numbers (dimensionless temperature differences) in a search for an ultimate regime where extrapolation to astrophysical conditions may become possible. Studies of the temperature distribution in the interior and of the LSC dynamics will be undertaken. A theoretical model of the LSC dynamics will be developed. The highly quantitative experiments are of modest complexity and thus afford an exceptional diverse learning experience for both graduate and undergraduate students who participate in the work.

非技术摘要：从下面加热的流体中的湍流对流自然发生在地球的大气层和海洋中，它影响气候和天气，在地球的地幔中，它有助于大陆板块的运动，在地球的外核中，它决定了磁场，在太阳中，它影响地球上的温度，以及在许多工业过程中，它可能具有显着的经济后果。该补助金将支持在高度受控的实验室条件下进行的实验，以及在理想形状的样品中进行的实验，其中可以定量研究该过程的一些中心物理成分。这些组件包括相对安静的流体层，位于底部上方和顶板下方（“边界层”），以及具有高度波动的温度和流体流动的湍流内部。一个被称为“湍流风”的大型对流单体叠加在这些内部波动上。 将对热输送的湍流增强、内部温度分布和风动力学进行定量测量。高度定量的实验是适度的复杂性，从而提供了一个特殊的多样化的学习经验，研究生和本科生谁参加work.Technical摘要：湍流对流流体加热从下面发生在许多地球物理，天体物理和工业情况。该补助金将支持在高度受控的实验室条件下进行的实验，以及在理想化的（主要是圆柱形）形状的样品中进行的实验，其中可以定量研究该过程的一些中心物理成分。这些部件包括顶部和底部边界层，以及具有高度波动的温度和速度场的湍流内部。一个大尺度流（LSC）叠加在内部波动。 将在最大可能的瑞利数（无量纲温差）下对热传输进行定量测量，以寻找可能外推到天体物理条件的最终状态。将对内部的温度分布和LSC动态进行研究。将开发LSC动态的理论模型。高度定量的实验是适度的复杂性，从而提供了一个特殊的多样化的学习经验，研究生和本科生谁参加的工作。