Development of an ultrasonic acoustic interferometer for silicate liquids in an internally heated pressure vessel

这个项目的目标是开发一种高压声学干涉仪，可以用来测量内部加热压力容器（IHPV）中硅酸盐液体的声速和密度（以及压缩性）。我们计划在高压下开发两种不同的技术：(1)测量液体声速的频扫法，(2)测量液体密度的反射系数法。我们将使用现有的可在0.3 GPa和1200摄氏度下操作的IHPV。这笔赠款的资金将用于各种设备和机械车间的费用，并部分支助一名全职技术人员。在高压下测量硅酸盐液体的密度和可压缩性是地球科学中一项重要的实验任务，特别是当它应用于含挥发物熔体时。这些数据需要精确的晶体-熔体和流体-熔体平衡的热力学计算，进而需要部分熔融、熔体输送、结晶和脱气以及岩浆喷发力学的定量模型。参与该项目的研究生将获得热力学，声学和信号处理以及岩石学和地球化学的强大背景。预计我们开发的技术将在整个超声和地球科学界得到广泛应用。

EAR-0447113Lange The goal of this project is the development of a high-pressure acoustic interferometer that can be used to measure the sound speed and density (and thus compressibility) of silicate liquids in an internally heated pressure vessel (IHPV). We plan to develop two different techniques at elevated pressure: (1) the frequency sweep method to measure liquid sound speed, and (2) the reflection coefficient method to measure liquid density. We will use an existing IHPV that is operable to 0.3 GPa and 1200 degrees celsius. Funds from this grant will be used for various equipment and machine shop costs and to partially support a full-time technician. Measurement of the density and compressibility of silicate liquids at high pressure is a major experimental imperative in the earth sciences, especially when applied to volatile-bearing melts. These data are needed for accurate thermodynamic calculations of crystal-melt and fluid-melt equilibrium at depth, which in turn are required for quantitative models of partial melting, melt transport, crystallization and degassing, and the mechanics of magma eruption. The graduate students involved in this project will obtain a strong background in thermodynamics, acoustics and signal processing, as well as petrology and geochemistry. It is anticipated that the techniques that we develop will become widely used throughout the ultrasonics and earth sciences community.