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User:ClemonsLemons/project 3

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Cheryl Campo

Turbine Project

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  • A turbine is a machine for producing continuous power in which a wheel or rotor, typically fitted with vanes, is made to revolve by a fast-moving flow of water, steam, gas, air, or other fluid.

Examples of Turbines:

Previous groups Final Project

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Previous Groups Final project Wikiversity page [:3D Printed Turbine]

Project Objectives

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  • Learn more about how turbines work and what are some of the applications for turbines
  • Familiarize with the 3D printer, its process, and its applications
  • Reprint some of the previous groups parts that are falling apart and that are unclean and have rough edges that may influence the outcome of the project
  • Develop a system that blows air into the front of the turbine in order to demonstrate a working final creation

Turbine

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Turbine Information
  • A turbine is a machine that generates continuous and unending power through the use of wheels or rotors that are typically fitted with curved vanes that capture some type of fuel in order to rotate that are attached to a centrally located rotating axis. These rotors apply the use of continuous streams of water, steam, gas, air, or other fluid to rotate the vanes.
Real world applications of turbines
Types of turbine generators
Synchronous generator
  • Used in almost all stand-alone applications
  • Single phase used up to 10 kW.
  • Most three phase are smaller than equivalent single phase
Induction generator
  • Just an induction motor with negative slip.
  • Used most often with grid-tie systems.
  • Used by some for battery based systems.
  • Simple and robust.
  • Readily available and inexpensive.
  • Requires external excitation from the grid or from capacitors
  • Control is more difficult, especially for inductive loads
  • It requires frequency controls if not tied to the grid
DC Alternator
  • Produces rectified alternating current.
  • Readily available.
  • Easy to service.
  • A rheostat controls excitation.
Wind turbine
  • When the wind meets the blades it starts to spin which causes the axle that is connected to the rest of the rotors to spin which produces mechanical energy.
    • This mechanical energy can be used for purposes such as grinding grain or pumping water.
    • The mechanical energy can also be connected to a generator in order to produce electricity
  • The specific parts of a wind turbine and how they work can be found on the following link
Wind Turbine Components

Tower

  • Hold up the turbine in the path of the wind

Control system

  • Controls functioning of turbine
  • Number of sensor fittings reading speed and direction of wind, levels of electrical power generation, rotor speed, blades pitch angle, vibration levels, lubricant temp
  • Computer processes inputs to carry out operation with safety system that is able to override controller when emergency occurs
  • Protects turbine from operating in dangerous conditions
  • Ensures power generated has proper frequency, voltage, and current levels to be supplied to the grid

Yaw drive system

  • Keeps rotors facing the wind and unwind cables traveling down the tower base
  • Consists of electric or hydraulic motor on the nacelle driving the pinion on a vertical shaft through reducing gearbox
  • Brake to stop the turning of turbine and stabilizing turbine during normal operation

Drive Train

  • Heart of wind turbine

Nacelle

  • Box like component sitting on top of turbine
  • Contains 8,000 components of a wind turbine. Includes: gearbox, generator, main frame
  • Housing made of fiberglass protecting internal components

Rotor

  • Spins the shaft connected to the generator

Made of

  • High-tech blades
  • Hub- made of ductile cast iron, weighs 8 to 10 tons. Located on front of blade
  • Spinner
Pros of a Wind Turbine
  • Does not pollute the surrounding area because it generates electricity by using a natural everyday occurrence to power the turbine
  • Enormous potential because no matter where you are there will always be wind to turn the turbines so you can potentially build anywhere
  • Renewable because we never will run out of wind to turn the turbines
  • Space Efficient because the turbine can fully power multiple homes and you are able to use the land that surrounds the turbines
  • Rapid growth: wind power only accounts for about 2.5% of total worldwide electricity production, the capacity is growing at an incredible rate of 25% per year (2010)
  • Prices are decreasing due to technological advances and increased demand
  • Low operational cost: the major cost to use turbines is actually building the turbines, once they are built the only need periodic operational checkups
  • People can generate their own power for their homes
Cons of a Wind Turbine
  • There is not always wind which makes it very unpredictable
  • Costs enormous money in order to build the turbines
  • Threat to wildlife: because the blades are so big there is a chance for flying animals to get killed by running into the blades, this is especially true on Wind Turbine Farms
  • For those living near wind turbines it generates a lot of noise that may keep you up late into the night
  • Wind turbines disturb the natural scenes because of their great size especially when you see a farm of wind turbines
Water turbine

Two types of water turbines

Impulse Turbine

How it Works

  • Fast moving fluid fired from a narrow nozzle thus spinning the turbine with bucket shaped blades that work by directing the fluid spray at an angle or sometimes even back the way it came.
  • Fluid is forced to hit the turbine at high speed
  • Water turbines are often based around an impulse turbine
Types of Impulse Turbines
Pelton
  • At least one jet of water strikes the bucket at atmospheric pressure
  • Maximum jet diameter is about 1/3 bucket width
  • More jets increase flow
  • Multiple Runners have the advantage of greater flow and flow control and may be placed in the same housing or separate housings
Turgo
  • More complex blade design then pelton runner
  • Greater flow possible
  • Multiple nozzles

Four to six nozzles may be added before splash interference occurs and the power output is proportional to the number of nozzles

  • Spear valve changes the nozzle sizes without the turbine stopping
  • Deflectors can be used to vary flow and usually used for emergency stop without causing water hammer
Crossflow
  • Banki or Mitchell turbine
  • Shaft oriented horizontally
  • Rectangular nozzle forms the jet
  • Water strikes the blade twice
  • A control vane changes jet size
  • Draft tube increases head
  • Longer Blades increase flow and power
  • Part flow is achieved with partition vanes
Reaction Turbine

How it Works

  • Blades of the turbine sit in a large volume of fluid that spins the blades as the water flows through it.
  • Unlike a impulse turbine where the water flow is redirected, in a reaction turbine the blade simply spins when the fluid flows through the blades
  • The most familiar examples of a reaction turbine is a wind turbine
Types of Reaction Turbines
Francis
  • Guide vanes may be adjusted by governor
  • Efficiency decreases as flow decreases
  • Water flow is radial from exterior to interior
  • Flow changes gradually from radial to axial
Propeller and Kaplan
  • Propeller is similar to a ships propeller
  • Has guide veins similar to Francis turbine
  • Kaplan has variable pitch blades
  • Part flow efficiency is poor
Pump as Turbine
  • Centrafugal pumps may be used as turbines
  • Low cost due to mass production
  • No direct correlation between pump charistics and turbine characteristics
  • Flow is fixed for a given head
Steam Turbine

How it Works

  • Cross between a wind and water turbine.
  • Like a wind turbine when steam blows past the blades they start to spin
  • Like a water turbine the blades are in a sealed contained unit so that the steam is constrained and forced to move past the blades
  • Use high-pressure steam that turns a electricity generator making them rotate faster then both a wind and water turbine

Similar to a water turbine, steam turbines can utilize both a impulse and reaction turbine blades

  • The impulse steam turbine has the same blades as the water powered impulse turbine. The steam in this type of turbine hits the blades pushing them around utilizing a series of impulses which then bounce off the other side of the blade with a velocity reduced pressure.
  • In a steam powered reaction turbine it includes a second set of blades that have been attached to the inside of the turbine case. The second set of blades helps to speed up and redirect the steam at the right angle where it leaves with a lower temperature and pressure but similar velocity as the steam when it first entered the turbine. Both of the blade sets are made of incredibly tough material that allow continuous high-pressure steam to be directed at them.

Components

  • Rotors and blades
  • Speed control mechanism
  • Set of nozzles that direct steam onto either the stationary or rotating blades
Real complete turbine

Stages of Real Steam Turbine

  • Multiple blades allow to extract the most energy it can before the steam is exhausted
  • Each of the sets of blades are called a stage which works by either impulse or reaction
  • Typical turbine has a mixture of both types of stage that are mounted on the same rotor as each other all turning the generator at the same time
  • Often the stage that comes first is the impulse then reaction stages. The impulse stages extract the energy from high pressure steam and the reaction stages remove extra energy from expanded steam volume which utilizing bigger and longer blades.
  • This multi-stage approach was invented by Charles Parsons who created it in a way that each of the stages of the turbine are slowly slowing or reducing the steam pressure. This reduces the forces applied on each blade which improves the overall power output

Project Work Documentation

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Week 1: 3D Printer Certification
Introduction to Makerbot

The Makerbot Replicator 2 is a 3D printer that extrudes a biodegradable thermoplastic (PLA) to create parts. This is the older and smaller of two Makerbot 3D printers at HCC, but it prints faster than the newer (5th Gen) model.

Warnings
  • Printing gun parts violates US Federal Law
  • Printing trademarked or actively patented stuff could result in a legal problems
  • The school can not support printing personal stuff including personal inventions
  • Focus printing on things that are related to engineering projects.
Quick Start Guide
  1. Find or create a 3D model of a part.
  2. Use MakerWare software to convert 3D model (STL file) into X3G file.
  3. Use Makerbot Replicator 2 to print part.
  4. Carefully remove the part from the build platform.

If you have a problem and don't know what to do, STOP and ask an instructor or lab aide for help.

Quiz for Makerbot Certification

quiz - Take this after reading through the tutorial, and before taking the Canvas quiz.

Old pages

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Replicator 2 MakerBot page

Original MakerBot Cupcake Tutorial Page

Week 2: Printing Parts

Objectives of the week

  • Create schematics of a few of the previous groups parts that need to be reprinted
  • Upload the parts onto a CAD program
  • Print created parts using the older and better 3D printer

Created Parts

Pieces waiting to be Approved

Next Steps

  • Print designed part on 3D printer
  • Replace previous groups printed piece with new printed piece
Week 3:Problem Identification and Problem Solving

Objectives

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  • Locate any problems that might cause the turbine to not work properly
  • Determine ways of eliminating the problems that occured

Objective 1

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Problems

  • Back blades are rubbing against each other and since they are on different shafts this affects the spinning motion of both shafts and the rotors on those shafts.

Solution: Move the pieces that are rubbing together apart

Remaining Problems

  • Front housing is not stable and not firmly connected with the big front housing
  • Housings don't stay connected when not attended to and fall apart if left alone

Next Steps

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  • Fix problem with front housings stability
  • Place each blade and rotor in its place and secure the position while allowing part to be removed when needed to be fixed or replaced
  • Connect the three different housings together to prevent it from falling apart when not holding it up in a way where they can be separated easily
  • Design and implement a way of transferring an air stream in a concentrated stream to spin the rotors and the rotary shafts
Week 4: Connectivity
Primary Week 4 Objectives
  1. Fix unstable big fan housing so that it is stable and doesn't wobble which would create friction between the blade and the housing
  2. Replace glue that fixed the blades and rotors to stick in one spot permanently which you may run into problems later on if you have to fix or replace one or more of the rotors and blades and are unable to be easily removed. Find a way to stick the rotors and blades in one place in a way that allows easy removal when having to replace the part.
  3. Create a removable way to stick the separate housing pieces together preventing it from falling apart that allows the next group to be able to remove the tubes, blades, and rotors
Objective Completion

Objective 1: Stabilizing front of turbine

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  • The nails that were placed onto the original groups turbine failed to have a hold on the drilled holes on the front housing so the nails kept on slipping out which caused the whole front part of the turbine unbalanced causing friction between the blade and the housing.
  • Replaced nails with screws to hold the turbine steady

Objective 2: Blade and rotor placement and attachment

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  • Previous group glued each piece to the tube making it so you have to get the glue of in order to remove the part if you need to replace that part.
  • Middle ring of the rotor was big enough that if you wrapped a piece of tape around where the parts are supposed to be located at. Tape creates a snug fit between the rotor and the rotary tube that allows part to be easily removed while once the turbine starts spinning the piece still stays in place.

Objective 3: Housing connecting

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The problem with using glue to connect the housings together is that they are unable to be separated. There are two ways of combating this problem:

  • Recreate and reprint the housing pieces with some kind of attached mechanism that fully connects the two housings together while being able to separate them if need be
  • Create a secondary attachment that allows the housings to connect with each other while still being able to separate

Solution to Problem: Velcro between the spot where the housings connect with each other on both sides of the housing and on the underside of the housing. Velcro holds the pieces together keeping the housings from separating while easily being able to disconnect the pieces.

  • Velcro keeps the pieces from being separated while the cylinder connectors attached to the housing keep the housings from being separated horizontally
Next Steps
  • Create something that closes off the turbine from the air except for the front and back of the turbine. Another choice would be to create a covering using the 3D printer to generate the pieces
  • Find or create bearings big enough enough to fit around the small inside rotary shaft allowing the turbine to spin easier with a lot less friction and if some friction remains find where it occurs and create a way to fix the problem.
  • Create a mechanism that directs a high enough stream of constant directed air that is able to spin the turbine
  • Real world applications of your built turbine
  • Create a different type of turbine and compare between turbines

Collective Turbine Final Work:

Project 3 Final: Turbine