NASA researchers recently demonstrated successful real-time fault detection and isolation of a virtual reusable launch vehicle main propulsion system. Using a detailed simulation of a vehicle propulsion system to produce synthesized sensor readings, the NASA team demonstrated that advanced diagnostic algorithms, running on flight-like computers, can, in real time, successfully diagnose the pres...

Since its founding, NASA has been dedicated to the advancement of aeronautics and space science. The NASA Scientific and Technical Information (STI) Program Office plays a key part in helping NASA maintain this important role. The NASA STI Program Office is operated by Langley Research Center, the Lead Center for NASA's scientific and technical information. The NASA STI Program Office provides ...

Abstract This paper identifies potential weaknesses and challenges of hydrogen fuel cell systems as main energy provider for electrified aircraft propulsion presents solutions. The general design, operating principles characteristics hydrogen-fuelled low-temperature polymer electrolyte membrane (PEMFCSs) are described. safety assessment process in aviation according to Aerospace Recommended Pra...

objectives: wheelchairs are the prime mobility aid of persons with spinal cord injuries. manual wheelchair propulsion puts a lot of demand on the cardiopulmonary as well as the skeletal system. the main purpose of the study was to compare the effects of both arm ergometry training and progressive resistance exercise training of upper limbs on resting heart rate and distance covered during wheel...

A study of low discharge voltage Hall thruster operation revealed the existence of two operating regimes. Small variations in cathode flow fraction and magnetic field resulted in sharp changes in discharge current with constant thrust, corresponding to a visible change in the jet-mode plume structure. The phenomenon is characterized with a systematic map of thruster operation for discharge volt...

A Faraday probe with three concentric rings was designed and fabricated to assess the effects of gap width and probe geometry in a systematic study of the Hall thruster plume. The nested Faraday probe consisted of two concentric collector rings and an outer guard ring, which enabled simultaneous current density measurements on the inner and outer collector. Two versions of the outer collector w...

An annular field reversed configuration (FRC) plasma concept is being developed by the Univeristy of Michigan and AFRL to investigate inductively-coupled high power electric propulsion. Presented is the continued exploration of an annular FRC with specific focus on main bank discharges, magnetized plasma toroid formation, and preliminary investigation into plasma translation. Additional detail ...

Towards direct simulations of counterflow flames with consistent differential-algebraic boundary conditions Report Title A new approach for the formulation of boundary conditions for the counterflow configuration is presented. Upon discretization of the steady-state Navier-Stokes equations at the inflow boundaries, numerically algebraic equations are imposed as boundary conditions, while upon d...

Having considered a number of possible future space activities and analysing their implications for future launch vehicle requirements in terms of economics, technological and policy aspects by overcoming the disadvantages of the current launch system, the development of the low-cost fully reusable new space transportation system to and from lower earth orbit, as driven by the clear need for af...

The Ultra High Temperature Ceramics (UHTCs) represent a very interesting family of materials and therefore they are the subject of increasing attention from different engineering sectors and notably the aerospace industry. Indeed, hypersonic flights, re-entry vehicles, propulsion applications and so on, require new materials that can perform in oxidizing or corrosive atmospheres at temperatures...