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Jet engines, airplanes, helicopters, car racing enthusiasts, wind generation, electricity generation, turbo chargers, vacuum cleaners, air compressors, and wind mills all involve turbines. Yet few know anything about them. A theory of operation; small, safe, models; and mechanism for testing them (video) is needed.


  • Demonstrate how turbines of various sorts work and where they are used. Inspiring video.
  • Develop compressed air driven models of various turbine engines.


Start with a jet-engine model found on Thingiverse.

How a jet engine works (Theory of Operation)
Parts of a basic jet engine

Video's explaining how jet engine works:

How the jet engine model works:

  1. Starter (left hand green air jet in model) is driven by compressed air in the model and an electric motor with electricity from the airport terminal in an airline.
  2. High Pressure Compressors (high speed) (small gold) are used to start the process. The compressed air is pushed past the green air jet (representing where the fuel will be inserted below) and pushed into the white low pressure turbines.
  3. The rear housing bearing cap is stationary. It acts like a nozzle curving the air between the white low pressure turbines for optimal power.
  4. The low pressure turbines turn the big gold intake turbine and the smaller white, low pressure compressors in the front.
  5. The low pressure turbines begin to force air through the left bearing cap. The bearing cap acts like a nozzle and curves the air so the high pressure compressors spin in the opposite direction.
  6. Light can be seen through the front fan on a real jet engine because birds, hail and water have to bypass the low pressure compressors. Air leaks in the model on purpose. In a jet, the combination of low and high compressors can evacuate the air in a 4 bedroom house in half a second, compressing the air 28 times higher than the input. Extra air is used at low speeds to help divert objects coming in through the front fan.
  7. The low pressure turbines spin at a lower speed and opposite direction to balance the torque. They power the the cabin (air conditioning, electricity) and they power the front fan (gold on the far right) and low pressure compressors.
  8. After the front fan and low speed compressor spins fast enough, fuel is added in the model by flowing compressed air through the right side green air jets. At this point the left side air jet representing the starter is no longer needed.
  9. Now electricity to power the cabin is available, the electric motor to the jet engine starter is turned off, so the electric power from the terminal is turned off, the cabin lights go out, everything is turned off, electric power from the jet engines is turned on and the lights come back on.
  10. There is a feedback loop that boosts power: Compressors pull/suck air -> Compressors shoot air into Combustion Chamber -> Combustion chamber expands air and shoots it out the back -> rushing air turns turbines -> turbines turn compressors -> compressors suck more air -> repeat
  11. The entire engine has the shape of a nozzle with the goal of shooting air out the back
Designing a transparent cover for the 3D-printed turbine

Considered two methods for covering the turbine compression chamber and housings.

Option 1 (Plexiglas):
a conceived method for bending plexiglas
Option 2 (Soda bottle):
Turbines in Wikicommons
Older Turbine Projects
Investigating Tread Mill Motor to attach wind turbine

Website containing exploded view of the original treadmill

Helicopter Turbine Engine

Helicopter engine turbine project video

The exhaust of this this engine is sent down the tail which uses the coanda affect to avoid a prop (turbine) at the end of the tail. This in effect causes the entire tail of the air craft to become a turbine.

Wind Turbine: Computer Fan

Here is the final soldered electronics including the resistors for the voltage divider, LCD connections, potentiometer, quick disconnect for the fan, and portable power source.

Final Code using LCD display
int sensorpin = A0; // input pin for power (positive)
int sensorValue = 0; // variable to store the value coming from the sensor
double Vout; // voltage output
double i; // amps (current)
double p; // watts 
double r1 = 7.5;
double r2 = 5.0;
double r = 12.5; // resistance value (ohms) 7.5k and 5k resistor
double c = 204.8; // constant value divider (1024 / 5) to get correct ratio. Analog pin reads up to 5v in 1024 increments.
#include <LiquidCrystal.h> // include the library code
LiquidCrystal lcd(12, 11, 8, 7, 4, 2); // numbers of the interface pins, more space between pins compared to last code
void setup() {
   lcd.begin(20, 4);  // sets up the LcD's number of columns and rows: 
   Serial.begin(9600); // initialize serial communication at 9600 bits per second:
void loop() { 
sensorValue = analogRead(A0);  // read the value from the sensor:    

Vout=(sensorValue/c) * (r2/r); //vout = vin(Divided by c to scale down to 5v) * r2/(r1+r2)
i=Vout/r; // current = V/r
p=Vout*Vout/r; // power = (V^2)/r
lcd.setCursor(0, 0);
lcd.print("Amps= ");
lcd.setCursor(0, 1);
lcd.print("Volts= ");
lcd.setCursor(0, 2);
lcd.print("Watts= ");
lcd.setCursor(0, 3);
lcd.print("SensorValue= ");
delay(500);        // delay in between reads for stability
Arduino code to measure voltage
/* Displaying Voltage input Using the Serial Monitor with Arduino
 Patrick Thoreson, 1 October, 2012 */

const int analogInPin = A0;  

void setup() {

void loop() {
  int sensorValue = analogRead(analogInPin);
 /* Serial.print("sensor = " );                       
  Serial.print(sensorValue);   */   
  Serial.print(" Voltage=");

  delay(100); // wait 1/10 of a second                    

double voltage(int analogIn){

  //double voltage = (analogIn/1023.)*32.2;

  return voltage;

Wind Turbine: Ceiling Fan

Tried to use ceiling fan motor (AC). A DC motor seemed easier. Would not need rectifier.

Wind Turbine: Car Fan
A Project Poster

Found the DC motor/generator in these videos in dual radiator fan from a car junk yard.

large wind turbine spinning in natural wind
small wind turbine over powering LED
small wind turbine powering LED
PVC fan blades

Table of LED chain that lights up more LED's as more power is generated:

First Diode Turn-on Second Diode Turn-on Third Diode Turn-on
1.7V 3.2V 5V
3mA 17mA 5.2mA
Shrouded Wind Turbine
Shrouded Wind Turbine

Inspired by OginEnergy's Turbine and the wikipedia entry Wind_lens, tried to see if could demonstrate the difference on a small scale with a lamp shade and a PC power supply fan. Drawings


Videos of Testing:

Traditional Bladed Wind Turbine
Shrouded Wind Turbine
Turbo Booster

This project created a turbo booster that was tested:

here is an active DIY Gas Trubine group who publishes video all over youtube.


Design Resources


Compressed Air Connection

Cabin fever demonstrates a variety of engines within a building. Most everything at this exhibit runs off of compressed air.

3D printed parts will not be operational until air compressors arrive. Future operation of turbines could go far beyond quick demos, they could be used to power other projects and tools.

The Thingiverse air jet pieces measured at a quarter inch (1/4in.) in diameter. Here is a beginning of items that may need to be purchased to hook to a compressor.

Assembly of 3D-printed turbine
  1. Began with printing and naming all parts
  2. Later re-named all parts on finished design (see two leftmost photos below)
  3. Used this Thingiverse page as a basic assembly guide
  4. Glued both housings to combustion chamber
  5. Glued all high-pressure parts together
  6. Glued low-pressure turbines onto low-pressure shaft
  7. Slipped high-pressure parts onto low-pressure shaft
  8. Glued low-pressure compressors to low-pressure shaft, with high-pressure parts in between low-pressure turbines and compressors
  9. Fit high and low-pressure parts onto housing. Filed, re-glued, and adjusted parts as needed.
  10. Cut any sticking out shaft to appropriate length. Added fan blades.
  11. Fit entire assembly onto Cowlings
  12. Placed clear plastic cover over turbine parts
Fixing 3D printed parts
  • Found flaws on many parts. The team named these flaws excess, because excess plastic stuck up in places where the surface had to be smooth. Here is how excess was removed:
Gluing compressors and turbines to shaft



Next Steps[edit]

  • develop theory of operation of helicopter engine by adding titles to the old helicopter turbine project
  • review cabin fever implementation
  • add clear shroud and compressed air to turbine and troubleshoot
  • design helicopter instead of jet turbine