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.
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.
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.
The rear housing bearing cap is stationary. It acts like a nozzle curving the air between the white low pressure turbines for optimal power.
The low pressure turbines turn the big gold intake turbine and the smaller white, low pressure compressors in the front.
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.
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.
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.
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.
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.
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
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):
STEP 1: Find 2-liter bottle and remove wrapping. Make sure it fits around turbine.
STEP 2: Measure 3D-printed turbine. Mark bottle at appropriate lengths.
STEP 3: Cut off top and bottom of bottle.
STEP 4: Cut a line parallel to the length of the bottle. Bottle should curl up as seen in photo.
STEP 5: Measure turbine and cut plastic to proper lengths. Bottle shown not cut appropriately due to lack of measuring tools and scissors in work environment.
STEP 6: Size up cover to fit turbine.
STEP 7: Measure turbine, mark cover, and cut precisely to fit perfectly.
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
Wind Turbine Completed with resistive load
Circuit box printed on 3D printer
Plexiglass cut with circular saw
Measuring circuit powered by 9V battery
video of testing LCD readout of voltage/current/power
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.
Close up of Soldered Pins
Soldered LCD board for Wind Turbine
Portable Power Source for Wind Turbine Electronics
Circuit design
Final Code using LCD display
intsensorpin=A0;// input pin for power (positive)intsensorValue=0;// variable to store the value coming from the sensordoubleVout;// voltage outputdoublei;// amps (current)doublep;// watts doubler1=7.5;doubler2=5.0;doubler=12.5;// resistance value (ohms) 7.5k and 5k resistordoublec=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 codeLiquidCrystallcd(12,11,8,7,4,2);// numbers of the interface pins, more space between pins compared to last codevoidsetup(){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:}voidloop(){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/rp=Vout*Vout/r;// power = (V^2)/rlcd.clear();lcd.setCursor(0,0);lcd.print("Amps= ");lcd.print(i);lcd.setCursor(0,1);lcd.print("Volts= ");lcd.print(Vout);lcd.setCursor(0,2);lcd.print("Watts= ");lcd.print(p);lcd.setCursor(0,3);lcd.print("SensorValue= ");lcd.print(analogRead(A0));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 */constintanalogInPin=A0;voidsetup(){Serial.begin(9600);analogReference(INTERNAL);}voidloop(){intsensorValue=analogRead(analogInPin);/* Serial.print("sensor = " ); Serial.print(sensorValue); */Serial.print(" Voltage=");Serial.println(voltage(sensorValue));delay(100);// wait 1/10 of a second }doublevoltage(intanalogIn){//double voltage = (analogIn/1023.)*32.2;returnvoltage;}
Wind Turbine: Ceiling Fan
Tried to use ceiling fan motor (AC). A DC motor seemed easier. Would not need rectifier.
Ceiling Fan
testing the voltage
had three speeds: inside, outside, inside+outside
inside coil was to far from the magnet to be able to generate a voltage
one of the coils in the outside coil had a major break
the break
Wind Turbine: Car Fan
A Project Poster
Found the DC motor/generator in these videos in dual radiator fan from a car junk yard.
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
Isometric view of The design of the turbine
Side view of The design of the turbine
Front view of The design of the turbine
Construction
Trying to remove case off of a PC fan
connecting the 2 shrouds together
Connecting the piece of wood to the shrouded PC fan so that the lamp shred would fit inside
Trying to remove the motor off of a PC fan
How the design for the double shrouded fan looks like
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.
Slipped high-pressure parts onto low-pressure shaft
Glued low-pressure compressors to low-pressure shaft, with high-pressure parts in between low-pressure turbines and compressors
Fit high and low-pressure parts onto housing. Filed, re-glued, and adjusted parts as needed.
Cut any sticking out shaft to appropriate length. Added fan blades.
Fit entire assembly onto Cowlings
Placed clear plastic cover over turbine parts
Labeled parts of Howard Community College's 3D printed jet-engine turbine. Part layout shows general configuration of parts in finished assembly.
The labeled parts of a 3D printed turbine design
Top view of jet-engine
Bottom of jet-engine
Low-pressure compressors
High-pressure compressors
Low and high-pressure turbines
A Jet Engine turbine printed from the Howard Community College Makerbot
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:
Before. Note jagged lines sticking up in middle of compressor.
After. Although not perfectly uniform in appearance, compression chamber is now smooth enough for compressors to spin with little resistance.
STEP 1: Use pliers to pull as much excess as possible
STEP 2: Use the tips of scissors or wire cutters to cut or pull finer excess that pliers could not reach. Be sure not to cut or scrape good parts of object.
Use safety goggles from here on, as plastic shavings may reach eyes.
STEP 3: Use a metal file to sand away as much excess and rough as possible.
Use edge of file to dig into more stubborn excess.
Plastic should still be rough and scratched. Use 150 grit sand paper to smooth plastic. Will not be able to reach perfection. Blow loose dust away.
STEP 4: Gently rinse with cool low-pressure water to wet remaining dust. Get only necessary parts of plastic wet.
STEP 5: Use fingers to rub away whetted dust until content.
STEP 6: Quickly dry off all water using a towel. Feel for any more excess, roughness, or edges. If not satisfied, file, sand, and/or rinse until content.
Chamber is now smooth enough for compressors and turbines to fit nicely.
Gluing compressors and turbines to shaft
FIRMLY GLUING PARTS: Slide part partially onto shaft. Apply hot glue where part is supposed to go.
FIRMLY GLUING PARTS: Slide part down shaft and over glued portion to proper location.
This low-pressure turbine had been poorly drilled, making it slip and tilt. Rather than trying to hot glue in precise orientation, glued directly to exhaust cone. Cone then fit tightly and properly onto axle with no additional glue required.
assembled
printed pieces
another picture of the printed pieces
