Laser-Induced Breakdown Spectroscopy of Hydrocarbon Flame and Rocket Engine Simulator Plume

Abstract

Laser-induced breakdownspectroscopy (LIBS) ofmetal-seeded aerosols and a hydrocarbon flame werestudied t o determine the pmper experimental condition for rocket motor application. LIBS and atomic emission spectroscop y (AES) were also performed in the rocket motor simulator to evaluate both technologies for the health monitorir g of the rocket engine. The LIBS signal of the seeded element goes down drastically in the presence of the flame i n comparison to the signal obtained from the aemsols of the elements. Similarly the LIBS signal of the trace elemen is was very weak in the luminous flame and the simulator plume in comparison to the messurement outside iL Tlre intensity of the LIBS signal from the trace elements pr€s€nt in the plume/flame was iound to be dependent on tlc process of seeding, the transition probabilitS and the decay time of the background emission. Ultimately LIBS wrs found to be more sensitive than AES in detecting the trace elements in the simulator plume. This study establish,s LIBS as an improved health-monitoring system over AES for the plume studied.