Inlet CFD Analysis
CFDRC engineers have conducted detailed analysis for both in-house and
3rd party applications, ranging from supersonic inlets to subsonic commercial
transport inlets. Analysis typically focuses on pressure recovery and
possible boundary layer separation. Shown below left is one quadrant of
a "quadfurcated" supersonic inlet for an ATR-powered missile,
while on the right is half of a bifurcated inlet at ground test conditions.
Inlet Protection Systems
Inlet systems for some vehicles, such as helicopters, must be able to
ingest significant quantities of sand, and separate these particles from
the core air stream so that the engine can function properly. CFDRC engineers
have supported our customers in conducting detailed inlet system analysis
to predict sand particle trajectory and separation characteristics. Shown
below is a generic inlet system in which almost all the sand bypasses
the main core flow.
For more information, please contact
us.
Ramjets and Scramjets
CFDRC can contribute on all levels of hypersonic vehicle analysis and
simulation.
Previous CFD activity has included the following areas:
- 2D and 3D inlet analysis
- Isolator and mixing analysis going into combustor
- Injection of hydrocarbon fuels in ramjet combustor
- 3D reacting flowfields in scramjet combustors
CFDRC personnel also have experience in running the 1D cycle codes:
- RJPA (JHU/APL)
- RAMSCRAM (NASA GRC)
Shown below is the Mach number field from a nose-to-tail analysis of
a Mach 5 ramjet-powered vehicle. The analysis featured discrete boundary
layer bleed in the inlet, injection and combustion of a hydrocarbon fuel
in the combustor, and the passing of the combustion products through a
choked throat and out the nozzle.
Air Turbo Rocket (ATR) Engine
CFDRC has developed engine cycle software to simulate all possible versions
of the ATR engine. Gas generator options include:
- Solid Propellant
- Liquid Bi-Propellant
- Liquid Monopropellant
- Turbo Hybrid (Paraffin)
Software includes specific maps of actual engine components.
Shown at right is the main page from the latest ATR analysis software
suite.
|
 |
Below is a schematic of a solid propellant ATR-powered tactical missile
For more information, please contact
us.
Liquid Rocket Engines
CFDRC engineers have developed and applied advanced computational spray
technologies and reaction dynamics to enable the transient simulation
of bi-propellant rocket engines, including start transients and motor
pressurization. The first figure shows the very initial stages of a transient
simulation involving the propellants IRFNA and MMH being injected from
7 unlike doublet paired elements.
Solid Rocket Motors
CFDRC personnel are knowledgeable on issues affecting solid propellant
motors and combustion. Capabilities include:
- Limited grain design and ballistics
- Internal burning
- Nozzle flow
- Throttleable Solids
CFDRC's APMOD pintle motor software can be used to design and analyze
axial pintle motors such as that shown to the right.
See also the Pintle
Motor section under Prototypes.
|
 |
For more information, please contact
us.
Solid Propellant Controls
CFDRC has several years of experience in developing technologies for
control of throttleable solid propellant systems. These include both solid
propellant gas generators, such as for ramjets, and throttleable tactical
solids. CFDRC's pintle-controlled SRM demonstrated on-demand thrust modulation
of a tactical solid. Shown below is a comparison of the final boost/sustain/re-boost
firing trace (blue) from CFDRC's pintle motor test bed program with the
original uncontrolled progressive burn (red).
Gelled Propellant Technology
CFDRC has experience in all phases of the use of gelled propellants for tactical
and strategic missile systems: mixing of gelled propellant, rheology of
gels in feed systems and combustion dynamics in the rocket chamber. Feed
system CFD modeling incorporates the Non-Newtonian flow behavior or the
propellants in steady state or transient simulations.
Electrostatic Atomization
CFDRC's advanced CFD flow solvers include special models for the droplet
breakup caused by electrostatically charging the droplets. This simulates
the true physical process.
For more information on our technologies and capabilities in this area
and to discuss your specific needs, please contact
us.
Return To Top |
