Arc-heated facilities at AEDC offer unique test capabilities for hypersonic programs

  • Published
  • By Rick Gamble
  • AEDC contributing writer
ARNOLD AIR FORCE BASE, TENN. --  The AEDC High Temperature Materials Characterization and Evaluation is unique in capability and is supporting test and evaluation (T&E) for current and future hypersonic programs.

Testing materials, such as those for thermal protection systems (TPS), is accomplished by using the Complex's high enthalpy arc-heated facilities to provide test conditions and simulate aeroheating from Mach 8 to 20 hypersonic flight.

Aerothermal ground test simulations over a wide range of velocities and pressure altitudes are conducted by AEDC's experienced high temperature test team. Using the arc heaters, the team is able to expose materials and components for long periods of time necessary to validate thermo-structural performance and survivability.

The team and these facilities support materials and structures development for the Department of Defense and commercial aerospace industry. They have assisted the development of ballistic and hypersonic missiles, re-entry vehicles, high-speed transports, space transportation and space access vehicles, and ordnance and munitions systems.

AEDC has three arc heaters, each with varying capabilities to address different testing needs.

The H1 Arc Heater is a test unit that incorporates a selectable number of cooled, electrically-isolated, stacked segments to optimize heater efficiency, total enthalpy and flow uniformity. Normal operating conditions produce high stagnation enthalpies and heater chamber pressures up to 120 atmospheres. A programmable rotary model injection system positions up to seven test TPS samples sequentially into the freejet for preset dwell times.

Like the H1, the H2 Arc Heater unit generates high-enthalpy flow at pressures up to 120 atmospheres. However, it also uses a non-segmented Huels arc heater and a hypersonic nozzle to expand flow into an evacuated test cell. Flight conditions between Mach 3.4 and 8.3 are possible.

The H3 Arc Heater has sufficient size and performance for testing full- and large-scale missile and reentry samples and structures. H3 is a 12 module, 50 percent geometric scale-up of H1 and operates at over twice the available power level and mass flow, with pressures up to 150 atmospheres.

For future T&E capability, AEDC is replacing the Huels heater in H2 with a segmented heater and upgrading its exhaust diffuser. This will enable the test team to reach test conditions required for Conventional Prompt Global Strike (CPGS) by 2017.