DEVELOPMENT OF THE OBSERVATION SYSTEM FOR THE BOUNDARY PHENOMENA IN THE HIGH TEMPERATURE FLUID.

本文发展了一种检测400℃以上高温加压熔体中气泡、固体颗粒及其混合物的超声波技术。第一年，根据一些单探头实验的结果，讨论和设计了整个装置的系统，如合适的频率、声功率等；第二年，建立了估算气液混合物中声学衰减和声速的数学模型。在研制用于高温熔体的硬件之前，从材料、形状、声场和耦合等方面进行了实验讨论。研究结果如下：(1)利用该数学模型对气泡-液体和固体微珠-液体两相体系中气泡和固体微珠的浓度和尺寸进行了估算。该模型也适用于三相系统。(2)实现了在超声探头中应用一些高能陶瓷作为缓冲棒。这些材料的使用使得系统成本低，用途广泛。(3)讨论了线性扫描探头类超声多探头的设计。(4)通过对锡液中固体颗粒和上升气泡的检测，发现该系统对高温熔体的适用性。

In this work, ultrasonic techniques was developed to detect the bubbles, solid particles and their mixtures in pressurized high temperature melts over 400 C.During the first year, total system of the apparatus, for example the suitable frequency, acoustic power etc., was discussed and designed by the results of some experiments with single probe.The following year, a mathematical model to estimate the acoustic attenuations and sound velocities in the mixture of gassolid liquid system was established. Prior to developing the hardware for application to high temperature melts, experimental discussion regarding the material, shape, acoustic field and coupling etc. were made. The results are as follows, (1) Concentration and size of bubbles and solid beads in two phase systems, gas bubble-liquid and solid bead-liquid are estimated by ultrasonic detection with the mathematical model. The model was also applied the three phase systems. (2) It was made possible to apply some high ceramics to the ultrasonic detecting probes as a buffer rod. The use of these materials made the system cost low and wide use. (3) The design of ultrasonic multi-probe like a linear scanning probe was discussed. (4) The applicability of this system to the high temperature melts was found by the detection of solid particles and rising up bubbles in the molten tin.