SBIR Phase I: A Fiber-Optic, Simultaneous, Multi-Point Turbulent Kinetic Energy Rate Dissipation Sensor

这一小型企业创新研究第一阶段项目提出了一种激光装置，用于测量海洋和实验室中的湍流动能耗散率。该传感器在许多海洋学/流体动力学应用中将是有价值的。例如，由于耗散率通常与摩擦速度的三次方成正比，因此它是对海底和表层边界层动力学最敏感的衡量标准；它对于海洋内部的观测同样至关重要，在那里，海洋中的混合对通过有机和地球化学颗粒输送进行碳循环的研究具有重要的基础意义和应用意义。新的传感器概念是基于对短时间段的加速度方差的无偏、直接估计，并随后使用泰勒假设对每个段进行空间梯度转换。激光设备不仅能够在提供欧拉耗散测量的固定平台上运行，而且还适用于比现有传感器测量的耗散率高得多的耗散率。最后，这里建议的能力不仅将提供单点测量，它将是一个基于另一项SBIR拨款正在进行的工作的同步多点传感器。由于欧拉测量的扩展能力、高耗散率范围和多点能力的结合，这一发展将对海洋学/流体动力学的广泛科学做出重大贡献。由此产生的仪器还将有助于研究海洋集合体的动力学，这些集合体假定根据消散微尺度而分裂。这一发展产生的耗散传感器将广泛用于研究海洋表面和海底边界层过程的科学家，研究生物初级生产力及其与湍流相互作用的其他科学家，以及研究海洋内部混合过程的科学家。

This Small Business Innovative Research Phase I project proposes a laser device for the measurement of the dissipation rate of turbulent kinetic energy in the sea as well as in the laboratory. The sensor would be valuable in a number of oceanographic/fluid dynamics applications. For example, since the dissipation rate scales typically with the third power of the friction velocity, it is the most sensitive measure of dynamics in the ocean bottom and surface boundary layers; it is similarly vital to observations in the ocean interior where mixing in the ocean is of strong fundamental interest as well as of applied interest in the study of carbon cycling via organic and geochemical particulate transport. The new sensor concept is based on the unbiased, direct estimation of acceleration variance for short-time segments, and subsequent conversion to spatial gradients using Taylor's hypothesis for each segment. The laser device will not only be able to operate from a fixed platform providing Eulerian measurements of dissipation, it is also suitable for much higher dissipation rates than can be measured with existing sensors. Finally, the capability proposed here will not only provide measurements at a single point, it will be a simultaneous multi-point sensor based on work in progress in another SBIR grant. Because of the combined capabilities of extension to Eulerian measurement, high range in dissipation rate and multi-point capability, the development could make significant contributions to a broad range of science in oceanography/fluid dynamics. The resulting instruments will also be useful in the study of dynamics of marine aggregates which are postulated to break apart depending on the dissipation microscales. The dissipation sensor resulting from this development will be of broad use of to scientists studying boundary layer processes on the ocean surface and bottom to other scientists studying biological primary productivity and its interaction with turbulence and to those studying mixing processes in the ocean interior.