Hypersonic Test Bed Development using Fiber Optic Sensing Technology

ABSTRACT:IFOS proposes to design and fabricate a hypersonic test bed using a research cone instrumented with optical fiber sensors. IFOS will demonstrate the feasibility of developing an innovative optical fiber based system to enable precision measurement of high-frequency heat flux/skin friction in hypersonic flows. The proposed sensing system is based on fiber Bragg gratings (FBGs) and will be mounted so as to be non-intrusive to the hypersonic flow. In Phase I we develop a test article design and fabrication process, and sensorize the test article with a new fiber optic heat flux and skin friction measurement system. We assess merits and deficiencies of each with respect to expected performance, fabrication, and testing. We will develop plans for hypersonic wind tunnel experiments. In Phase II, we will produce more test articles, conduct extensive hypersonic wind tunnel tests, and collect wind tunnel and other performance data for the test article and demonstrate utility for computational tool application and CFD modeling and simulation validation.BENEFIT:The proposed diagnostic system will have Phase III application within an Air Force sponsored ground or flight research campaign to high Mach numbers. Initial work would develop techniques that can be applied in many different hypersonic tunnels. These verified techniques could then be used to measure heat flux on other geometries of interest, such as blunt geometries of interest to NASA, cowl inlets on scramjet vehicles, hypersonic gliding reentry vehicles (for Earth and other planetary atmospheres) and other geometries of interest to the Department of Defense and NASA.