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Mach and Speed of Sound Calculator allows you to specify the altitude and speed (or Mach) of an aircraft and the program uses the standard day atmosphere mathematical model to determine the speed of sound and the Mach number (speed) of your aircraft. Altitudes vary from 0 to 250,000 feet and Mach number varies from 0 to 25. Calculations are in English or Metric units.

Isentropic Flow Calculator solves the isentropic flow equations for a variety of inputs. Variables include the Mach number, static to total pressure, temperature, and density ratios, dynamic to static pressure ratio, critical area ratio, corrected airflow per unit area, Mach angle, and Prandtl-Meyer angle. Specifying any one variable determines the value of all the other variables.

Shock Wave Simulator solves the flow equations for supersonic flow past a 2D wedge, as described in NACA Report 1135. Input variables include the Mach number, and wedge angle. Depending on the combination, an attached oblique shock or a detached normal shock is generated. The simulator computes the static and total pressure ratio, the temperature and density ratio, the shock angle and the downstream Mach number. A graphic shows the shock angle.

Supersonic Cone Simulator solves the flow equations for supersonic flow past a cone, as described by the Taylor-Maccoll method. Input variables include the Mach number, and wedge angle. Depending on the combination, an attached oblique shock or a detached normal shock is generated. The simulator computes the static and total pressure ratio, the temperature and density ratio, the shock angle and the downstream Mach number. A graphic shows the shock angle.

Multiple Shock Wave Simulator solves the flow equations for supersonic flow past multiple wedges. Input variables include the Mach number, wedge angles, and the spacing between the wedges. Wedges may be located in series or opposite each other. Depending on the combination, attached oblique shocks or a detached normal shock is generated. The simulator computes the static and total pressure ratio, the temperature and density ratio, the shock angle, flow turning, and the downstream Mach number. A graphic shows the multiple shock intersections and reflections. This program also solves the single wedge problem; generating an oblique or normal shock, or a centered expansion fan.

There is an even more powerful version of the Multiple Shock Wave Simulator which is available for very experienced users. This program is a Java application, not an applet. It runs stand alone and you must have Java installed on your computer to run this program. The chief advantage of this program is that it can write files on your computer. You can save the output from the program to a file for printing.

MOC Nozzle is a simulator that performs a Method of Characteristics analysis of several different nozzle problems. The program works in three modes: analysis and design, design with plume into a static flow, and design with plume into a supersonic external flow. In any of the modes, you can change design variables including the design Mach number, throat area, plenum total pressure and temperature, external Mach number, and altitude. You can design 2D or axisymmetric ideal nozzles, external cowl nozzles or plug nozzles, or analyze simple cone or wedge nozzles.

There is an even more powerful version of MOC Nozzle which is available for very experienced users. This program is a Java application, not an applet. It runs stand alone and you must have Java installed on your computer to run this program. The chief advantage of this program is that it can read and write files on your computer. You can save your nozzle design and performance to a file for printing. You can also save your current design to a "Save" file. At your next session you can read the "Save" file information back into the program and continue your design.

Interactive Nozzle Simulator solves the isentropic flow equations for the flow through a rocket nozzle, a converging- diverging turbine nozzle or a converging turbine nozzle. Input variables include the throat area, throat to exit area ratio, total pressure and temperature in the plenum, and free stream pressure. You can select from a variety of propellant combinations, or specify your own molecular weight, ratio of specific heats, and combustion temperature. Output include the flow through the nozzle, the thrust, specific impulse, exit velocity and Mach number, and exit static pressure. This program does not design the surfaces necessary to produce a desired uniform exit flowfield; it only insures conservation of mass.

Supersonic Flows Simulator solves the flow equations for a variety of supersonic flows. The program is a collection of many of the other supersonic flow simulations described on this page. The current version of the program (Jan 2013) can solve the following problems:
1. Flow past a single wedge.
2. Taylor-Maccoll flow past a cone.
3. Shock-on-shock interactions.
4. Centered Prandtl-Meyer expansions.
5. External compressions inlets.
6. Shock diamonds from the exit of a nozzle.
7. Preliminary 2D nozzle design using method of characteristics (MOC).
8. Preliminary axisymmetric nozzle design using MOC.

EngineSimU is a simulator that performs a Brayton Cycle analysis of a turbine engine or ramjet. The program works in two modes: Design Mode or Tunnel Test Mode. In the Design Mode, you can change design variables including the flight conditions, the engine size, the inlet performance, the turbo machinery compressor and turbine performance, the combustors or burner performance, or the nozzle performance. For a turbofan engine design you can also vary the fan performance and the bypass ratio. When you have a design that you like, you can switch to the Tunnel Test Mode, where you can vary only the flight conditions (airspeed, altitude, and throttle setting).

EngineSimU is a special version of the EngineSim program that includes all of the options of the original version plus an additional input panel. Using this panel, you can reset the limits on all of the variables in the program.

There is an even more powerful version of EngineSimU which is available for very experienced users. This program is a Java application, not an applet. It runs stand alone and you must have Java installed on your computer to run this program. The chief advantage of this program is that it can read and write files on your computer. You can save your engine design and performance to a file for printing. You can also save your current design to a "Save" file. At your next session you can read the "Save" file information back into the program and continue your design.

FoilSimU III is a simulator that performs a Kutta-Joukowski analysis to compute the lift of an airfoil, and a table look-up of experimental data to determine the drag of the foil. The user can control the shape, size, and inclination of the airfoil and the atmospheric conditions in which the airfoil is flying. The program includes a stall model for the airfoil, a model of the Martian atmosphere, and the ability to specify a variety of fluids for lift comparisons. The program has graphical and numerical output, including an interactive probe which you can use to investigate the details of flow around an airfoil.

TunnelSys is a simulator to design, test, and analyze the performance of a wind tunnel model of an aircraft wing. TunnelSys combines three computer programs, a design program, a wind tunnel test programs, and a post-processing program, which can be operated by three different students to explore the process involved with wind tunnel testing. The wing analysis is based on FoilSim III.

Beginner's Guide to Aerodynamics
Beginner's Guide to Propulsion
Beginner's Guide to Hypersonics
Beginner's Guide to Compressible Aerodynamics
Beginner's Guide to Model Rockets
Beginner's Guide to Kites
Beginner's Guide to Wind Tunnels
Free Software
Aerospace Activities and Lessons
Aerospace Resources

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