AeroRocket Engineering The sole source for AeroCFD, FinSim, AeroSpike and HyperCFD  MAIN PAGE  SUMMARY OF EXPERIENCE  Providing Affordable Aerodynamics Software Since November 1, 1999


Latest Publications
"Rocket Spin Stabilization Using Canted Fins",
SpinSim (2002)


Nozzle 10:
Nozzle
is a onedimensional and twodimensional,
compressible flow computer program for the analysis of
convergingdiverging nozzles, including ramjet and scramjet engines. Nozzle models inviscid, adiabatic and hence isentropic flow of a
calorically perfect gas through variablearea ducts. Nozzle internal flow may be entirely subsonic, entirely
supersonic or a combination of subsonic
and supersonic including
shock waves in the diverging part of the nozzle. Shock waves are
clearly identified as vertical red lines on all plots. The crosssectional
shape in the axial direction of the nozzle is specified by selecting
from five standard nozzle types or by defining nozzle geometry
using the FreeForm nozzle geometry method. Nozzle plots color
contours of pressure ratio, temperature ratio, density ratio,
and Mach number and has a slider bar that displays realtime values
of all nozzle flow properties. New in this version is the ability
to determine shockangle, jetangle (plumeangle) and Mach number
for axisymmetric and twodimensional nozzles in the region near
the lip for underexpanded and overexpanded flow. The convergingdiverging nozzle
featured in the new AeroRocket supersonic blowdown wind tunnel
was designed
using
Nozzle
applying the concept of a normal shock diffuser. FinSIM 10 and the new Flutter Velocity Tool: Quickly and easily predict fin flutter velocity, UF and fin divergence velocity, UD for any rocket while specifying fins in the Fin Geometry screen by simply using a slider bar. Predict flutter velocity from sea level all the way to maximum altitude that was defined on the main AeroFinSim analysis screen. Get instant flutter velocity feedback while specifying fin geometry and get an idea of fin shock angle and fin Surface Mach number that a fin will experience during supersonic flight. Flutter velocity accuracy is enhanced by using the NASA web site atmospheric model that predicts free stream pressure (P) temperature (T), density (r)and speed of sound as a function of altitude from sea level while flying through the Troposphere (h < 36,152 feet), Lower Stratosphere (36,152 feet < h < 82,345 feet) and finally the Upper Stratosphere (h > 82,345 feet). The atmospheric model used in FinSim is not limited to only the Troposphere or 36,152 feet. AeroCFD^{®} is a "true" threedimensional axisymmetric and twodimensional implicit finite volume CFD program that solves the inviscid Euler equations for subsonic, transonic and supersonic flow using automatic mesh generation and graphical results visualization. AeroCFD provides a maximum of 100 cells in the axial direction, 50 cells in the transverse direction and 10 cells in the circumferential (3D) or thickness (2D) direction. The latest version of AeroCFD has increased the number of discrete finitevolumes available for analysis from 18,000 cells to 50,000 cells. Due to its "true" 3dimensional formulation, AeroCFD provides nonzero lift and nonzero pitching moment for axisymmetric shapes at angle of attack without requiring computational times exceeding one hour. Model geometry is specified by selecting from a library of standard shapes. Nose sections are defined using one of five basic shapes that include Conical, Ogive, Elliptical, Parabolic and SearsHaack with power series coefficient. The user has the option for adding up to two constant diameter sections, one variable diameter transition section and one variable diameter boat tail section to complete the library of userdefined shapes. For added flexibility AeroCFD can import up to 1,000 XR data points for generating axisymmetric and twodimensional designs that require grid clustering in regions where shock waves dominate the flow. The RESULTS section clearly displays FX, FY, MZ, CX, CY, CM, CD, CL, base drag, surface friction drag and center of pressure location. Flow fields are displayed using fillcontour plots, linecontour plots and surface distribution plots for pressure coefficient, pressure ratio, temperature ratio, density ratio and Mach number. All output can be sent directly to a color printer. AeroSpike performs an expansionwave analysis from the throat of the thruster nozzle, where Mn = 1.0, to the thruster nozzle internalexit as a series of simple wave expansions. Then, for the external ramp AeroSpike performs a series of PrandtlMeyer expansions from the lip of the cowl, where R=Re, to the entire length of the external ramp of the aerospike nozzle. The ideal contour or shape of the external ramp of the aerospike nozzle is determined using isentropic supersonic flow theory. Then, depending on whether the flow is underexpanded or if the flow is overexpanded AeroSpike performs either a PrandtlMeyer expansion analysis or an oblique shock wave analysis to determine the angle of the outer flow boundary from the lip of the cowl. As a by product of the oblique shock wave analysis AeroSpike determines the shock wave angle for overexpanded flow and plots both the outer boundary contour and the initial shock wave from the lip of the cowl. StarTravel performs twobody astrodynamics analyses of spacecraft and satellites knowing burnout velocity and flightpath angle at burnout. For this purpose StarTravel uses twobody astrodynamics theory for determining suborbital, orbital and interplanetary motion around the Earth and Sun. In addition, StarTravel performs general heliocentric and Hohmann Transfer orbital analyses for determining minimum velocity and flight time required for travel from Earth to other planets in the solar system. StarTravel also has a Solar System Calculator for animating orbital motion of the planets around the Sun. Finally, StarTravel uses the Special Theory of Relativity to determine elapsed time on Earth and aboard our starship when speeds approach the speed of light and determines the relativistic Doppler frequency shift of star light observed by our starship in the form of a color contour plot of the firmament. New in the latest version is the ability to determine the ballistic trajectory of rockets and missiles launched vertically, horizontally and everything in between. 

Additional Links 

Author's viXra eprint archive 
Warp Drive Research  Contact AeroRocket  


