HO-18-C020 -- Use of Optical Distributed Sensors for Spatial Temperature Measurements in HVAC&R Research PDF

In this paper, we will summarize the principles of operation of a distributed temperature measurement systems using fiber optics and variable frequency laserand a coherent optical frequency domain reflectometer. We will then present experimental results characterizing temperature distribution along a water tubecooled due to natural convection. These measurements are confirmed with conventional thermocouple measurements co-located within the test section.Demonstration of the viability of this technique for HVAC&R related work opens up the possibility of understanding temperature distributions in airflow, temperature glides of zeotropic mixtures, coil tube surface measurement and other applications of interest to ASHRAE.