Spacecraft & Hypersonic Vehicles
CFDRC develops multi-physics software technologies and delivers expert engineering design services for spacecraft, hypersonic vehicles, and re-entry systems. Programs we have supported with expert engineering services include Space Shuttle, Orbital Space Plane, X-43A Hyper-X, Beagle-2, Orion, and others.
Aero-thermodynamic Modeling & Simulation
Vehicles flying through the atmosphere at hypersonic speeds excite the air surrounding them to very high temperatures in the post-shock and boundary layer regions. Various chemical reactions associated with the elevated temperatures of these regions are initiated as a result. CFDRC ADS has developed fully-coupled finite rate chemistry with an arbitrary number of species models, as well as thermal non-equilibrium models. The models are designed to handle flows with a calorically perfect gas, or with thermo-chemical non-equilibrium gas. These technologies have been incorporated into our CFD-FASTRAN and Unified Flow Solver (UFS) codes.
- Space Shuttle Re-entry modeling
- Orion CEV Thermal Seal Analyses
- Trans-atmospheric Vehicle Design
- X-43A Hyper-X Vehicle Analyses
- Cargo Transfer Vehicle (XTV)
- Waverider Hypersonic Glide Vehicle
Launch Abort Systems
Crew abort systems are a significant driver in human spacecraft design, requiring a detailed understanding of multi-moving body separation, aero-thermal heating effects, plume impingement from separation motors, integrated flight controls, and parachute recovery systems. Human-rated designs must also consider the physiological effects of acceleration loads, stability and control induced loads, and blast induced loads translated through a spacecraft to the crew compartment. In collaboration with NASA and private industry, CFDRC has developed and applied modeling and simulation technologies for crew abort or escape system (CES) applications, mitigating risk through optimized designs that reduce the complexity and weight that would otherwise be added to compensate for uncertainties in crew abort scenarios.
- Apollo/Saturn launch escape system studies
- Space Shuttle crew escape simulation
- Orbital Space Plane CES modeling
- X-38 Crew Return Vehicle (CRV)
- Orion CEV Launch Abort System (LAS)
Planetary Aero-capture Systems
Aero-capture systems allow space vehicles to decelerate near a planet to enable atmospheric entry for a controlled descent and landing in the surface. Inflatable ballute structures have emerged as a promising enabling technology for future planetary exploration. In ballute systems, a large, inflatable space structure can be launched in its collapsed configuration to a destination in space where the structure is subsequently deployed to full size to slow the space vehicle for descent and landing. CFDRC has developed a multi-disciplinary analysis tool for predicting the impact of aeroelastic and aerothermal effects on the functionality of inflatable aero-capture systems in both the continuum and rarefied flow regimes.
- Tightly coupled fluid-structure interaction (FSI) simulation of thin film ballute system concepts, such as the NASA Inflatable Re-entry Vehicle Experiment (IRVE)
- Modeling & simulation of hybrid isotensoid inflatable fabrics such as Ultra High Performing Vessel (UHPV) for Mars deceleration atmospheric entry applications
- Developed an aerodynamic-coefficient database for the ESA Beagle 2 Mars probe, covering the entire entry trajectory, from Mach 1.5 to Mach 28, and angles-of-attack up to 30 degrees
Lunar Lander Plume Analyses
Soil liberated by rocket plume impingement can cause significant damage and contaminate co-landing spacecraft and surrounding habitat structures during Lunar or planetary landing operations. CFDRC and the University of Florida are developing an innovative simulation system for predicting surface erosion and debris transport caused by Lunar surface rocket plume impingement. Advanced multi-physics numerical methodologies have been incorporated in the UFS tool for accurate predictions of plume interaction with lunar soil.
- Development of a fundamentally improved granular mechanics model for realistic lunar soil
- Accurate multi-phase modeling by integrating the UFS (continuum-rarefied gas phase) and soil erosion model (solid phase) through an Eulerian-Eulerian approach
- Developed Lagrangian debris transport model for mixed flow regimes, and realistic lift/drag forces on soil particles
- Boundary layer analysis of hypersonic rocket exhaust plume flow under lunar environment
- Analysis on the unsteady or streaking effect of surface roughness on plume boundary layer
In-Space Propulsion Thruster Design
Various advanced mono- and bipropellant rocket engines are being developed by NASA and DoD for in-space propulsion applications such as orbital maneuvering and station keeping. Such engines typically use hypergolic propellants from a single injection element and expand the reaction products through a nozzle to vacuum. The reactive flow conditions in the rocket chamber are very complex, and are sensitive to various geometric parameters and operative conditions. CFDRC has experience performing physics-based modeling and simulation to understand the internal reactive flow field associated with thruster design concepts, which is essential for satisfying optimum performance and mission reliability requirements.
