Turbulant Convection in a Fluid Heater from Below

非技术摘要：从下面加热的流体中的湍流对流自然地发生在地球的大气层和海洋中，在那里它影响气候和天气，在地球的地幔中，它有助于大陆板块的运动，在地球的外核，它决定着磁场，在太阳中，它影响地球上的温度，以及在许多工业过程中，它可能会产生重大的经济后果。这笔赠款将支持在高度受控的实验室条件下和在理想形状的样品中进行实验，在这些样品中，可以对这一过程的一些核心物理成分进行定量研究。这些组件包括底部上方和顶部板块下方相对安静的流体层(“边界层”)，以及具有高度波动的温度和流体流动的湍流内部。在这些内部起伏上叠加了一个大型对流单体，被称为“湍流之风”。将对热量输送的湍流增强、内部温度分布和风的动力学进行定量测量。这些高度定量的实验具有中等的复杂性，因此为参与这项工作的研究生和本科生提供了非常多样化的学习体验。技术摘要：从下面加热的流体中的湍流对流在许多地球物理、天体物理和工业环境中都会发生。这笔赠款将支持在高度受控的实验室条件下和在理想化的、主要是圆柱形的样品中进行实验，在这些样品中，可以对这一过程的一些核心物理成分进行定量研究。这些组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。大尺度流(LSC)叠加在内部涨落上。热传输的定量测量将以尽可能大的瑞利数(无因次温差)进行，以寻找可能对天体物理条件进行外推的最终制度。将进行内部温度分布和LSC动力学的研究。建立了LSC动力学的理论模型。这些高度量化的实验具有适度的复杂性，因此为参与工作的研究生和本科生提供了异常多样化的学习体验。

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.