Temperature and Viscosity in-Situ Sensor for Hostile Processes

Viscosity of a fluid is known to affect the reflection of shear waves from a solid/fluid interface. In this paper, we will discuss the experimental work to simultaneously measure both temperature and viscosity of a fluid at very high temperatures using a buffer rod technique. The sensor is based on the effect of melt viscosity on ultrasonic shear wave reflections from the solid-melt interface. We have used refractory materials for the solid buffer rod delay line which is water cooled. The sensor has been calibrated using various calibration samples and has been tested for repeatability. A portable instrument and a database has been created for temperatures up to 1500 degree Celcius. The results based on this sensor and their interpretations will be discussed. This sensor can find applications both as a process monitor as well as a tool for improving melter design for high temperature melt processes