In-Situ Measurement Of Temperature And Pressure In Fluid Films Using Ultrasound

Measuring and controlling temperature and pressure isof paramount importance to ensure safe and thrivingconditions for life, and reliable operation for machines andprocesses. Conventional measurement techniques areseldom suited to confined environments and tribologicalcontacts. This work aims to enable in-situ measurementof temperature and the pressure of any confined liquidlayer. To achieve this, an ultrasonic viscosity measurementdevice equipped with a matching layer was repurposed.Changes in the operating conditions caused theexpansion and compression of the matching layer, inturn causing a time shift of the ultrasonic signal. Thetemperature range spanned from 20 °C to 60 °C, whilepressures were measured from ambient pressure up 600MPa. It is further proposed that tailoring the material ofthe matching layer to the expected operating conditionscan enhance both the sensitivity and accuracy of themeasurements.