Laser-Based Diagnostics for Arc Heated Flows

Arc jet facilities are crucial tools in the development of thermal protection materials for vehicles re-entering Earth’s atmosphere. These facilities are designed to simulate the heat load experienced during re-entry. To ensure that the arc jet tests provide the desired conditions, the state of the test gas in the arc jet facility must be accurately known. Existing instrumentation on the arc jets at Arnold Engineering Development Center (AEDC) relies on the use of probes which perturb the flow and which cannot distinguish between the multiple species comprising the flow. PSI proposes to develop and deliver to AEDC a laser-induced fluorescence system to provide non-intrusive, real-time measurements of several key properties of the flow, including number densities of atomic oxygen and atomic nitrogen, flow velocities, translational temperatures, and spatial profiles of the atomic species. As a result, the facilities operators at AEDC will be able to provide more accurate testing services to their customers in the US Air Force and in the aerospace industry.