Mathis Effusivity Sensor Package (ESP) Technology: Principles of Operation

摘要

Mathis effusivity sensor package (ESP) system measures effusivity of materials, based on the transient hot strip technique. It is used mainly as an online or inline process monitoring and control system in various industries such as pharmaceutical and cosmetics. Examples of applications are real time monitoring of the uniformity of blended powders in motion, and monitoring of drying processes. Presently, the system is being modified for applications that require thermal conductivity measurements up to 40 W/mK and temperature up to 200°C. The system combines a reduced calibration technique with improved algorithms that compensate for variations in sensor temperature, thus enabling reliable effusivity measurements seamlessly in a wide range of temperatures. In this paper, some aspects of the system are reviewed. The review includes theoretical principles, design considerations for the sensor and system, sensor calibration, uncertainty evaluation of measurements and finally typical experimental results are reported.