Spectrally-Resolved Laser Diagnostics for High-Enthalpy Flow Measurements
Abstract
PUBLICLY RELEASABLE PROJECT SUMMARY The Hanson Research Group at Stanford University proposes the development of new spectrallyresolved laser absorption spectroscopy (LAS) and laser induced fluorescence (SR-LIF) diagnosticstrategies targeting nitric oxide (NO), oxygen (O2), and potassium (K) in order to address a range ofcritical needs for improved non-intrusive and quantitative sensing capabilities in high-enthalpy airflows, particularly in the context of hypersonic ground testing. These needs include the measurementof gas temperatures (kinetic, rotational, vibrational), composition, velocity, mass flux, static pressure,and excited state populations under both equilibrium and non-equilibrium conditions.Hypersonic ground test facilities, such as blowdown tunnels, impulse tunnels, and arcjets, present anumber of unique sensing challenges, including high stagnation temperatures, reactive compositions,sensitivityto flow perturbation, and the need for fast response, that ultimately limitthe utility of manyconventional in-situ sensing approaches (e.g., wetted flow sensors like thermocouples and pitotprobes). These challenges inherently hinder the insights gained through hypersonic ground testing andlimit the data available to evaluate and improve the computational tools under development to modelboth multi-physics hypersonics phenomena and hypersonic vehicle performance.Ongoing research efforts at Stanford University in collaboration with a number of facility partners(e.g., AEDC, NASA Ames, Caltech) aim to address this need for improved sensing capabilities inhigh-enthalpy flow facilities through the development and implementation of new non-invasive, highbandwidth,and portable sensor strategies, capable of measuring composition, temperature, pressure,velocity, and quantum-state-specific populations.In this proposal, weaim to build upon our previous successes field-deploying a high-bandwidth KbasedLAS sensor, applying the SR-LIF concept to NO, OH, and K, and pushing SR-LIF to kHzmeasurement rates (supported by the ONR Hypersonic Aerothermodynamics, High-Speed Propulsionand Materials program under Dr. Eric Marineau).1#3To that end, the following research objectives are proposed:1. Develop, validate, and demonstrate kHz-rate UV-based LAS and SR-LIF diagnostics targetingnitric oxide and oxygen for measurements of temperature, pressure, velocity, and compositionin high-enthalpy air2. Develop, validate, and demonstrate 100+ kHz-rate LAS and SR-LIF diagnostics targetingpotassium for measurements of temperature, pressure, and velocity in high-enthalpy air3. Support the development, implementation, and broad adoption of field-deployable sensorsbased upon this work in academic, industry, and government high-enthalpy ground testfacilitiesThe fundamental knowledge gained by this effort would enable a suite of new non-intrusive highbandwidthsensors for directly addressing Navy measurement needs in hypersonic ground testing.[Approved for public release]
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 03, 2023
- Source ID
- N000142312303
Entities
People
- Ronald Kent Hanson
Organizations
- Office of Naval Research
- Stanford University
- United States Navy