System Validation Experiments for Obtaining Tracer Laser-Induced Fluorescence Data at Elevated Pressure and Temperature

Jason Hartwig; Gaurav Mittal; Kamal Kumar; Chih-Jen Sung

doi:10.1177/0003702817746409

System Validation Experiments for Obtaining Tracer Laser-Induced Fluorescence Data at Elevated Pressure and Temperature

Appl Spectrosc. 2018 Apr;72(4):618-626. doi: 10.1177/0003702817746409. Epub 2017 Dec 27.

Authors

Jason Hartwig¹, Gaurav Mittal², Kamal Kumar³, Chih-Jen Sung⁴

Affiliations

¹ 1 Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH, USA.
² 2 189455 Department of Mechanical Engineering, Graphic Era University , Dehradun, Uttarakhand, India.
³ 3 Department of Mechanical Engineering, University of Idaho, Moscow, ID, USA.
⁴ 4 242752 Department of Mechanical Engineering, University of Connecticut , Storrs, CT, USA.

PMID: 29164904
DOI: 10.1177/0003702817746409

Abstract

This paper presents a set of system validation experiments that can be used to qualify either static or flow experimental systems for gathering tracer photophysical data or conducting laser diagnostics at high pressure and temperature in order to establish design and operation limits and reduce uncertainty in data interpretation. Tests demonstrated here quantify the effect of tracer absorption at the test cell walls, stratification, photolysis, pyrolysis, adequacy of mixing and seeding, and reabsorption of laser light using acetone as the tracer and 282 nm excitation. Results show that acetone exhibits a 10% decrease in fluorescence signal over 36 000 shots at 127.4 mJ/cm², and photolysis is negligible below 1000 shots collected. Meanwhile, appropriately chosen gas residence times can mitigate risks due to pyrolysis and inadequate mixing and seeding; for the current work 100 ms residence time ensured <0.5% alteration of tracer number density due to thermal destruction. Experimental results here are compared to theoretical values from the literature.

Keywords: Acetone; LIF; absorption; laser-induced fluorescence; photolysis; pyrolysis.