The measurement of droplet temperature using thermochromic liquid crystals

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:442581

Peterson, D; Hu, S H; Richards, C D; Richards, R F ^[1]

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1. Washington State Univ., Pullman, WA (United States). Dept. of Mechanical and Materials Engineering

A noninvasive technique to determine the temperature of droplets in flight is under development. The technique involves atomizing droplets of neat thermochromic liquid crystals and then inferring the droplet temperatures form the liquid crystals` color-play. Previous work has shown the feasibility of atomizing the neat liquid crystal. The present work reports results of a calibration of the temperature response of 200 to 300 micron droplets of neat liquid crystal. The calibration is accomplished by suspending droplets of the neat liquid crystal on a microthermocouple within a controlled temperature environment. The droplet is imaged using a long-distance microscope, an RGB video camera, and a frame grabber. Images of the droplet are acquired and digitized to quantify changes in RGB values (color) with temperature. The RGB information is transformed into hue, saturation, intensity (HSI) space to relate hue, H, to temperature. The temperature of the droplet is measured directly with the micro-thermocouple.

• Sponsoring Organization: Washington State Univ., Pullman, WA (United States); National Science Foundation, Washington, DC (United States)
• OSTI ID: 442581
• Report Number(s): CONF-950828--; ISBN 0-7918-1707-5
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
ATOMIZATION
CALIBRATION
COLOR
DROPLETS
HEAT TRANSFER
LIQUID CRYSTALS
TEMPERATURE DEPENDENCE
TEMPERATURE MEASUREMENT
TWO-PHASE FLOW