Hypersonic Vehicle Electric Power System (HVEPS)

 

In 2002-2003 CLA led the UTSI research program to help develop MHD generators for a new generation of high-speed Air Force vehicles. The generator would provide short bursts of high power electrical energy to supply laser or other beamed energy weapon systems. UTSI’s effort, part of a program led by General Atomics, focused on computational modeling of the MHD generator and sub-scale tests of MHD generators for validation of design codes. A gap in funding during the second half of FY03 and the first half of FY04 resulted in decreased activities during this time. However, FY04 and FY05 funding were received, and the project continues to operate under these funds. During the last year, (1) the combustion test facility flow field characterization was completed, and (2) the facility was prepared for the installation of a subscale MHD generator with superconducting magnet.

The HVEPS test program will be completed during the next fiscal year with the testing of a subscale MHD generator/superconducting magnet. Diagnostics utilized during combustor facility flow characterization and the upcoming MHD generator tests provide data to help validate an advanced 3D electromagnetic CFD code that can be used in analyzing the detailed physical behavior in a MHD generator. When validated, this code will be an invaluable tool in the future development of MHD generators.

 Photograph of a total pressure probe exiting the flow exiting the facility. This probe, designed in-house, survived the multiple passes through the plume.

Principal Investigator: Dr. T. Moeller
Sponsor: US Air Force through a General Atomics sub-contract

Future Use of the Combustion Facility

With the HVEPS program coming to a close in the near future, the combustion driven test facility will be available for use in other programs. This facility burns jet fuel in gaseous oxygen to provide a Mach 2 flow with static temperatures exceeding 2700 K at the nozzle exit. This facility could be utilized in the study of new test materials for hypersonic thermal protection and propulsion systems, including thermal barrier materials, catalytic materials, and non-catalytic materials. The facility can also provide data for the evaluation of new thermal probe analysis techniques, such as those developed by Jay Frankel at UT in Knoxville [1, 2]. Frankel’s techniques allow for the determination of surface temperature and heat flux using temporal data from a single embedded thermocouple. Additional embedded thermocouples allow for the assessment of material thermal properties. Frankel’s analysis techniques have been utilized to determine preliminary estimates for the surface temperature and heat flux at two locations in the UTSI combustion-driven test facility nozzle. Temperature data associated with thermocouples embedded in the UTSI combustor nozzle and the associated projected surface temperatures and fluxes are shown in Figures 4 and 5. Dr. Moeller, in collaboration with Dr. Frankel, is submitting multiple whitepapers and proposals to pursue further development of this analysis approach.

 Normalized temperature data from two thermocouples embedded in combustor nozzle wall and projected temperatures based on half-space solutions. Data taken from a two-second combustor test.

 Normalized surface heat flux determined from two thermocouples embedded in combustor nozzle wall (half-space solution). Data taken from a two-second combustor test. Notice proposed inverse method [2] produces well-behaved (stable) predictions.

References:

  • Frankel, J.I., “Generalizing the Method of Kulish to One-Dimensional Unsteady Heat Conducting Slabs”, AIAA J. Thermophysics and Heat Transfer, Vol. 20, #2, pp. 945-950 (2006).
  • Frankel, J.I., “Regularization of Inverse Heat Conduction by Combination of Rate Sensors Analysis and Analytic Continuation”, J. Engineering Mathematics, Vol. 57, pp. 181-198   (2007).