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[attachment=2377]
EDDY CURRENT BRAKES
EDDY CURRENT:
It is a swirling current set up in a conductor in response to a changing magnetic field.
By Lenz's law, the current swirls in such a way as to create a magnetic field opposing the change
Eddy Current Brakes
It slow an object by creating eddy currents through emi which create resistance, and in turn either heat or electricity.
Braking action is made by varying the strength of the magnetic field.
¢ A braking force is possible when electric current is passed through the electromagnets.
THEORY OF OPERATION
Eddy current brakes develop torque by the direct magnetic linking of the rotor to the stator.
This linking generates eddy currents in the driven rotor.
Eddy current brakes must have a slip between the rotor and the stator to generate torque.
An eddy current brake having an electromagnetic pole and the rotor is positioned in close proximity to the stator with an air gap between them
The stator comprises steel pole pieces with hollow cores that establish a magnetic circuit for a magnetic flux field.
The pole pieces have machine-wound electrical windings.
The windings are fastened with pole caps.
The hollow core reduces the weight and material of the stator without significantly adversely affecting the braking capacity.
The pole caps reduce the magnetic saturation and increases the overall brake torque output.
WORKING PRINCIPLE
Electromagnets produce magnetic field from supplied current
Change of magnetic flux (with time) induces eddy currents in conductor (disc)
Eddy Currents produce another magnetic field opposing first field
Opposing magnetic fields create force that reduces velocity
CONSTRUCTIONAL DETAILS
Components
Electromagnets
Cast Iron Core
Conducting (Copper) Wire
Mounting bolts
Disc
Mild steel
Machined from plates
It consists of two members, a stationary magnetic field system and a solid rotary member, generally of mild steel, which is sometimes referred to as the secondary because the eddy currents are induced in it.
Two members are separated by a short air gap, they're being no contact between the two for the purpose of torque transmission.
Consequently there is no wear as in friction brake.
Stator consists of pole core, pole shoe, and field winding.
The field winding is wounded on the pole core.
Pole core and pole shoes are made of east steel laminations and fixed to the state of frames by means of screw or bolts.
Copper and aluminum is used as winding materials.
CLASSIFICATION OF EDDY CURRENT
BRAKES
Linear eddy current brakes
It consists of a magnetic yoke with electrical coils which are being magnetized alternately.
This magnet does not touch the rail (held at approx 7 mm.)
When the magnet is moved along the rail, it generates a non-stationary magnetic field which generates electrical tension and causes eddy currents.
These disturb the magnetic field in such a way that the magnetic force is diverted to the opposite of the direction of the movement.
The braking energy of the vehicle is converted in eddy current losses which lead to a warming of the rail.
Circular eddy current brakes
When electromagnets are used, control of the braking action is made possible by varying the strength of the magnetic field.
A braking force is possible when electric current is passed through the electromagnets. The movement of the metal through the magnetic field of the electromagnets creates eddy currents in the discs.
These eddy currents generate an opposing magnetic field, which then resists the rotation of the discs, providing braking force.
The net result is to convert the motion of the rotors into heat in the rotors.
Advantages. . .
It uses electromagnetic force and not mechanical friction
Non-mechanical (no moving parts, no friction)
Fully resettable
Can be activated at will via electrical signal
Low maintenance
Operates at any rotational speed
Light weight
Disadvantages. . .
Braking force diminishes as speed diminishes with no ability to hold the load in position at standstill.
That could be considered to be a safety issue, but it really means that friction braking may need to be used as well.
Eddy-current brakes can only be used where the infrastructure has been modified to accept them.
APPLICATIONS
It is used as a stopping mechanism in trains.
It is also used in the smooth breaking and functioning of roller coasters and such fast moving machines.
CONCLUSION
¢ The ordinary brakes which are being used now days, stop the vehicle by means of mechanical blocking. This causes skidding and wear and tear of the vehicle. If the speed of the vehicle is very high, it cannot provide that much high braking force and it will cause problems.
¢ These drawbacks of ordinary brakes can be overcome by a simple and effective mechanism of braking system 'The eddy current brake'.
¢ It is an abrasion-free method for braking of vehicles including trains. It makes use of the opposing tendency of eddy current
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[attachment=4709]
eddy current brake full report
contects
EDDY CURRENT:
It is a swirling current set up in a conductor in response to a changing magnetic field.
By Lenz's law, the current swirls in such a way as to create a magnetic field opposing the change
Eddy Current Brakes
It slow an object by creating eddy currents through emi which create resistance, and in turn either heat or electricity.
Braking action is made by varying the strength of the magnetic field.
• A braking force is possible when electric current is passed through the electromagnets.
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I want full report on this topic 'Eddy current brake' with following sub heading : Introduction,Problem Identification and Its Objective,Methodology/Construction Details/Working Principle,Advantages and Disadvantages,Applications,Future Scope,
Conclusion,References.Kindly send me this by 19 Oct 2010.
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i want a working, operating principle,constructional details, advantageous, disadvantages,and its applications send with in one week.please ra
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Plz send some more data about eddy current brakes to prepare report on it
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EDDY CURRENT BRAKES
EDDY CURRENT:
It is a swirling current set up in a conductor in response to a changing magnetic field.By Lenz's law, the current swirls in such a way as to create a magnetic field opposing the change
Eddy Current Brakes
It slow an object by creating eddy currents through emi which create resistance, and in turn either heat or electricity.Braking action is made by varying the strength of the magnetic field. A braking force is possible when electric current is passed through the electromagnets.
THEORY OF OPERATION
Eddy current brakes develop torque by the direct magnetic linking of the rotor to the stator.This linking generates eddy currents in the driven rotor.Eddy current brakes must have a slip between the rotor and the stator to generate torque.An eddy current brake having an electromagnetic pole and the rotor is positioned in close proximity to the stator with an air gap between themThe stator comprises steel pole pieces with hollow cores that establish a magnetic circuit for a magnetic flux field.The pole pieces have machine-wound electrical windings.The windings are fastened with pole caps.The hollow core reduces the weight and material of the stator without significantly adversely affecting the brakingcapacity.The pole caps reduce the magnetic saturation and increases the overall brake torque output.
WORKING PRINCIPLE
Electromagnets produce magnetic field from supplied currentChange of magnetic flux (with time) induces eddy currents in conductor (disc)Eddy Currents produce another magnetic field opposing first fieldOpposing magnetic fields create force that reduces velocity
CONSTRUCTIONAL DETAILS
ComponentsElectromagnetsCast Iron CoreConducting (Copper) WireMounting boltsDiscMild steelMachined from platesIt consists of two members, a stationary magnetic field system and a solid rotary member, generally of mild steel,which is sometimes referred to as the secondary because the eddy currents are induced in it.Two members are separated by a short air gap, they're being no contact between the two for the purpose of torque transmission.Consequently there is no wear as in friction brake.Stator consists of pole core, pole shoe, and field winding.The field winding is wounded on the pole core.Pole core and pole shoes are made of east steel laminations and fixed to the state of frames by means of screwor bolts.
Copper and aluminum is used as winding materials.
CLASSIFICATION OF EDDY CURRENTBRAKESLinear eddy current brakes
It consists of a magnetic yoke with electrical coils which are being magnetized alternately.This magnet does not touch the rail (held at approx 7 mm.)When the magnet is moved along the rail, it generates a non-stationary magnetic field which generates electricaltension and causes eddy currents.These disturb the magnetic field in such a way that the magnetic force is diverted to the opposite of the directionof the movement.The braking energy of the vehicle is converted in eddy current losses which lead to a warming of the rail.
Circular eddy current brakes
When electromagnets are used, control of the braking action is made possible by varying the strength of themagnetic field.A braking force is possible when electric current is passed through the electromagnets. The movement of themetal through the magnetic field of the electromagnets creates eddy currents in the discs.These eddy currents generate an opposing magnetic field, which then resists the rotation of the discs, providingbraking force.The net result is to convert the motion of the rotors into heat in the rotors.
Advantages. .
. It uses electromagnetic force and not mechanical frictionNon-mechanical (no moving parts, no friction)Fully resettableCan be activated at will via electrical signalLow maintenanceOperates at any rotational speedLight weight
Disadvantages. . .
Braking force diminishes as speed diminishes with no ability to hold the load in position at standstill. That could be considered to be a safety issue, but it really means that friction braking may need to be used aswell.Eddy-current brakes can only be used where the infrastructure has been modified to accept them.
APPLICATIONS
It is used as a stopping mechanism in trains.It is also used in the smooth breaking and functioning of roller coasters and such fast moving machines.
CONCLUSION
The ordinary brakes which are being used now days, stop the vehicle by means of mechanical blocking. Thiscauses skidding and wear and tear of the vehicle. If the speed of the vehicle is very high, it cannot provide that
much high braking force and it will cause problems
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Submitted By
U.SUNIL KUMAR
[attachment=12352]
EDDY CURRENT BRAKES
ABSTRACT:
Many of the ordinary brakes, which are being used now days stop the vehicle by means of mechanical blocking. This causes skidding and wear and tear of the vehicle. And if the speed of the vehicle is very high, the brake cannot provide that much high braking force and it will cause problems. These drawbacks of ordinary brakes can be overcome by a simple and effective mechanism of braking system 'The eddy current brake'. It is an abrasion-free method for braking of vehicles including trains. It makes use of the opposing tendency of eddy current
Eddy current is the swirling current produced in a conductor, which is subjected to a change in magnetic field. Because of the tendency of eddy currents to oppose, eddy currents cause energy to be lost. More accurately, eddy currents transform more useful forms of energy such as kinetic energy into heat, which is much less useful. In many applications, the loss of useful energy is not particularly desirable. But there are some practical applications. Such an application is the eddy current brake.
EDDY CURRENT BRAKING:
Eddy current brakes are simple magnetic devices that consist of a non-ferromagnetic conductor that moves through a magnetic field. An example is shown in Figure 1 where a magnetic field is created in the gap of a toroidal electromagnet, with diameter D. When the conductive disc rotates, eddy currents are induced at an average distance R from the axis of rotation where the pole’s magnetic field moves as a function of the angular velocity of the disk.1 Power is dissipated in the conductive disk by the Joule Effect, which creates a viscous-like torque applied to the disk.
INTRODUCTION:
Eddy currents are one of the most outstanding of electromagnetic induction phenomena. They appear in many technical problems and in a variety of everyday life situations. Sometimes they are undesirable because of their dissipative nature (e.g. transformer cores, metallic parts of generators and motors etc). In many other cases, however, eddy currents are valuable (metal detectors, coin recognition systems in vending machines, electricity meters, induction ovens, etc). However, little attention is paid to eddy currents in many of the textbooks commonly used in introductory physics courses they are often dealt with only from a phenomenological point of view, and they are considered in some cases only as a topic for optional reading Furthermore, most of the commercially available experimental setups concerning eddy currents treat only their qualitative aspects. This paper presents a set of laboratory experiments intended to help students better understand the phenomenon from a quantitative point of view.
Above figure is the sketch of eddy currents in a rotating disc. The crosses represent a steady magnetic field perpendicular to the plane of the disc. According to Faraday’s law, eddy currents appear in those points of the disc where the magnetic field increases or decreases.
PRINCIPLE OF OPERATIONS;
Eddy current brake works according to Faraday's law of electromagnetic induction. According to this law, whenever a conductor cuts magnetic lines of forces, an emf is induced in the conductor, the magnitude of which is proportional to the strength of magnetic field and the speed of the conductor. If the conductor is a disc, there will be circulatory currents i.e. eddy currents in the disc. According to Lenz's law, the direction of the current is in such a way as to oppose the cause, i.e. movement of the disc.
Essentially the eddy current brake consists of two parts, a stationary magnetic field system and a solid rotating part, which include a metal disc. During braking, the metal disc is exposed to a magnetic field from an electromagnet, generating eddy currents in the disc. The magnetic interaction between the applied field and the eddy currents slow down the rotating disc. Thus the wheels of the vehicle also slow down since the wheels are directly coupled to the disc of the eddy current brake, thus producing smooth stopping motion.
Theoretical foundation
Induced currents appear when electrical conductors undergo conditions of variable magnetic
flux. In particular, we talk about eddy currents when bulk conductor pieces instead of wires
are involved. There are two basic procedures to achieve such conditions:
• exerting a time-varying magnetic field on a static piece;
• exerting a steady magnetic field on a moving one.
An example of the latter class will be investigated. It consists of a rotating metallic disc, which is subjected to the magnetic field present at the gap of an electromagnet. Eddy currents appear inside the disc and brake its rotation. This is the foundation of the electromagnetic braking systems used by heavy vehicles such as trains, buses or lorries. Even in such a geometrically simple case, the pattern of eddy currents is complex. Figure 1 and [3] show simplified sketches of this pattern. It is easy, however, to obtain an approximate expression for the power dissipated by eddy currents. Since the magnetic field B is steady, the induced electric field in each point of the disc is given by E = v × B, where v is the velocity of that point [4]. Instead of measuring B directly, we will relate it to the excitation current Iex in the coil of the electromagnet, which is easily measurable. For the moment we will assume that B is proportional to Iex (the validity of this hypothesis, which is not true for magnetic media, will be discussed later). Then the following proportionality law holds:
E ∝ ωIex
where ω is the angular speed of the disc. This means that for any loop of eddy current the induced electromotive force, being the line integral of the induced field, is also proportional to ωIex . Finally, the basic laws of electric current state that the power dissipated in that particular loop is proportional to the square of the electromotive force and to the inverse of the electrical resistivity of the disc. The same holds for the power dissipated in the whole disc:
Pe = K ω2I 2 exρ(1)
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PRESENTED BY:
Rodney Kremer
Aaron Noel
Mike Martinez
James Witt
[attachment=13009]
Eddy Current Brake Mechanism
Introduction
Sponsor
Outline
Background of current Honeywell application
Customer needs
Functional requirements
Constraints and Design effects
Ideal Final Result
Final Design
Analysis
FMEA-Disc Component
Ideality
Bill of Materials
Plans For Next Semester
Background
Honeywell’s current disconnect system
Shear neck
Not effective with variable speeds
Irreversible
Cannot be activated at will
Honeywell’s new disconnect
Needs activation system
Schematic of Shear Neck
Customer Needs
Decelerates ball screw nut to activate disconnect system
Produce required differential torque within given constraints and parameters
Recommended use of eddy current brake system
Mission Statement
Our mission is to develop, design, and test an innovative braking mechanism that will activate a mechanical disconnect system, applicable in a broad range of aerospace generators.
Functional Requirements
Activate Disconnect
Unscrew the ball-screw nut
Be Resettable
Maintenance free
Constraints
Eddy Current Brake
Produce magnetic field
Changing of Magnetic flux induces eddy currents
Eddy Currents produce another magnetic field opposing first
Opposing magnetic fields create force that reduces velocity.
Eddy Current Brake Rationale
Frictionless
Resetable
Light Weight
Few moving parts
Honeywell Recommendation
Components
Electromagnets
Cast Iron Core
Conducting (Copper) Wire
Mounting bolts
Disc
7075 Aluminum
Machined from plates
FMEA - Disc component
Driving Factors for Disc Design
Stress in Disc
Due to Imbalance
Due to Eddy Current Force
Due to Rotating Disc
Temperature of Disc
Electrical Conductivity
Density
Modeling Stress Due to Imbalance
Stress Due to Eddy Current Force
Force on Disc from Eddy currents
Stress Due to Rotating Disc
Heat Transfer (assumptions)
Disc is approximated as flat plate with average velocity, V
Radiation Heat Transfer Rate is Negligible
Disc Rotation Rate 7,200 RPM
Thermo-physical of oil mist can be approximated with that of engine oil
Neglect Heat Transfer out of outer edge of the disc
Neglect Conduction through Disc/shaft mating surface
Eddy Current Force Analysis
Preliminary MATLAB analysis
Faraday Software
Verification
Optimization
Single vs. Paired Electromagnets
Constant vs. Alternating Polarity
Relative Proximity
Coil Shape
Radius
Number of electromagnets/pairs
Visualization
Test Rig
Test Rig Supports
Design Matrix
Ideal Final Result
Predictable and Scalable Torque
No weight
Perfectly balanced
No parts
No frictional contact
Lasts Forever
Takes up no space
Operates at any angular velocity
Needs no power supply
Maintenance Free
Ideality
Bill of Materials
Plans for Next Semester
Continue Remaining Analysis
Build the Test Rig
Build ECBS
Testing and Optimization
Develop Final Product
Faraday’s Law
Equations used with Faraday’s Law:
Lenz’s Law, ,
Induced Current by changing magnetic Flux
Faraday’s Law & Eddy Current Brake Theory
Our understanding of Eddy Current
Relation of Faraday’s Law and Eddy Current brake
Ampere and Faraday’s Equations: &
Design Concepts
A single electro-magnet
Two electro-magnets of opposite Polarity
Two electro-magnets on each side of disc
Rotating arms of electro-magnets
Problem Statement
Activate an existing disconnect system for high-speed Aerospace generator
Non mechanical
Resettable
Activated at will (variable speeds)
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13-06-2011, 03:21 PM
I request for eddy current brake full report
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eddy current brake full report
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[attachment=15477]
1. Executive Summary
The Eddy Current Brake Mechanism team has been given the task of designing a braking system that will create a differential torque for the activation of a Honeywell Aerospace Generator Disconnect. This document will state the problem with the current Honeywell disconnect system and how we have taken the voice of the customer into consideration in coming up with a Final Design that will analytically produce the necessary torque for disconnect activation, thereby fulfilling the requirements set by Honeywell Corporation. Upon establishing a Final Design we will explain how the design works and why this particular design is ideal for application for disconnect activation. Our Final Design will comply with all given environmental, functional, and financial constraints and conditions, which will also be clearly defined within this document as well as showing how they were taken into consideration for our design. Seeing as we do not have the capability to transport any testing equipment from Honeywell, the production of a test rig was another task required of us for proof of concept and design. This report will discuss how our design will work within all technical specifications including the test rig’s ability accurately simulating all conditions. We will establish an innovative solution to an existing irreversible, damaging, and costly disconnect system.
2. Introduction
2.1. Document Purpose
The objective of this report is to establish an understanding of requirements set by Honeywell and presenting a conceptual design that fulfills those requirements that will later be put into production and become standard equipment on Honeywell generators. This report will present an Eddy current brake activation system per request of Honeywell. We will present analysis of an Eddy Current Brake System which will lead into why an Eddy Current Brake design is superior to other forms of disconnect activation which we will rule out on various systematic ways.
To give a brief overview, this document will include a problem statement and background as well as all customer needs for Honeywell’s current activation system. Upon establishing the Background and Problem Statement this report will include a brief Conceptual Solution which will adhere to the broad variety of Technical Specifications, also included in this report. The Technical Specifications will present various forms of constraints and information that will be considered and discussed in more detail about their influence in the Design Concept and Structural Analysis portions of this report. The following presents information included within this report:
2.2. Problem Statement
A disconnect system on a high-speed generator serves as a safety device. The disconnection occurs between the gear box and the generators drive shaft in order to prevent further propagation of failure. A disconnect system has already been developed and now needs and activation system. For more information on the disconnect system see Appendix A.
We have been given the task of designing an activation system that triggers this disconnection. A preference has been set in terms of function in the design of our innovative disconnect system. The problem with the current setup occurs with multiple disconnects. With the current design disconnection can happen once, then must be repaired before the generator and it’s disconnect will function again. We must design a reset able and reversible activation system that operates at variable speeds while remaining maintenance free.
2.3. Background
The disconnect system currently in use by Honeywell for a high speed generator comes in the form of a simple mechanically based part called a shear neck located between the generator and the gear box. For the shear neck to perform its function as a disconnection, the shear neck itself creates an additional constraint. The shear neck is design around a certain angular acceleration/velocity thereby limiting its ability to activate when desired. As a result, the shear neck might not engage at a certain angular acceleration/velocity. Once the shear neck does perform its function properly, and at the required torque, the shear neck must be replaced, hence making this particular disconnect system irreversible. Due to the irreversible nature of the shear neck and lack of function at variable speeds, the shear neck design proves very costly and labor intensive. Elimination of such a mechanically dependant component will prove extremely beneficial to the Honeywell corporation.
2.4. Customer Needs
Honeywell is a well respected and innovative company that develops vast amounts of products for both military and commercial applications. The innovative asset is important to the Honeywell Corporation; they must stay one step ahead of their competition at all times. We feel Honeywell has given us the opportunity to become an innovative asset to their company and help in their advancement of aerospace generators. Our contacts, Simon Waddell and Balwinder Birdi, have been extremely helpful in guiding us through the process of developing their new disconnect activation system.
Honeywell needs a new form of activation for their generator disconnect system. In order for the disconnection to take place we must provide a differential torque to decelerate a ball-screw-nut. The differential torque must also comply with all of the given Technical Specifications. The differential torque is the primary need. If the differential torque is not provided then disconnection fails. With the Technical Specifications given and the torque needed, Honeywell recommended designing an Eddy Current Brake System (ECBS).
2.5. Conceptual Solution
We took Honeywell’s recommendation and concluded that for the given Technical Specifications, the Eddy Current Brake System is an ideal final solution. The ECBS contains few moving parts and is completely free of contact with the exception of a disc being fastened to a drive shaft. Our team came up with a few other ideas aside from the ECBS that have their own strengths and weaknesses. Some of those concepts are:
Table #2: Design concepts
Design Concept Strengths Weaknesses
A Fluid Driven Turbine Brake
Use of bleed air
Non Electric
Potentially light weight Difficult to design/analyze
Requires pumps and release valves
Design around certain RPM
Reverse Direction Motor
No frictional contact
Motors are well established Heavy rotating parts/complicated controller
Heating
Angular Momentum Brake
Analytically simple
Impervious to EMP Many heavy moving parts
Physical contact
All of these were ruled out for the various reasons given as weaknesses. The ECBS turns out to fulfill all of the Technical Specifications and with further analysis we will find a reasonable torque for the ECBS design to prove itself as the superior design of the main for concepts. This report will go into a more thorough description and analysis in section five titled “Final Design” starting on page 15.
3. Technical Specifications
3.1. Voice of Customer
Following our meeting with Honeywell representative Balwinder Birdi, we discussed our notes taken from that meeting and clarified any information that seemed unclear. Upon reviewing our meeting notes we developed an all inclusive “voice of the customer” needs. From the “voice of the customer,” we broke up the needs into constraints and functional requirements. The constraints were then broken down into four sub-categories. We present those categories as:
• Environmental Conditions
• Operational Conditions
• Functional Conditions
• Budget
• Test Rig Properties
These conditions and constraints have certain properties that will limit our design and will be discussed in the following sections.
3.1.1. Functional Requirements
Our team determined the top level Functional Requirements are; Activate the generator disconnect, be reset-able, and be maintenance free. We will discuss how our final design will encounter and fulfill the functional requirements of our projects. With these functional requirements set we will also establish an ideal final result which we will not achieve but a goal to come as close as possible to attain.
3.1.2. Design Parameters
3.1.3. Constraint and Conditions
We broke down the constraints and conditions into sub-categories. Those categories cover the Environmental Conditions, the Operational conditions, Functional Conditions, the Budget as well as Test rig properties and physical limitations. The given constraints include; operation at a certain RPM, a limited power source, and operation in an oil mist environment just to cite a few examples. In addition to the given constraint, we established a couple of implied constraints. These implied constraints come in the form of developing a test rig or physical limitations. In the next section we will discuss these constraints and properties in more detail and what part of the design it might inhibit.
3.2. Environmental Conditions
3.2.1. Temperature
We were given a temperature constraint of the brake to operate between -50 degrees Fahrenheit to 300 degrees Fahrenheit. This constraint sets a design limitation that must take into consideration the materials used for our design.
3.2.2. Humidity
The brake has to function in an environment containing a range of 10% to 80% humidity. This will obviously limit out choice of materials because we do not want the material to deteriorate due to moisture. Other than material choice we don not believe this will limit our design any more than material choice. The humidity may even act as an aide in the cooling of a braking system.
3.2.3. Balance
Our design must be balanced to 0.005 oz. in. for all rotating parts. This precedence was established by Honeywell so the rotating parts will not have an effect on the operation of the generator. An imbalance will create an additional stress in the rotating part as well. The effect an imbalance will have on our design will be discussed in the Final Design section of this report.
3.2.4. Oil Mist
The Braking system will operate in an oil mist environment. This will create a limitation for a couple of our design concepts, however will create an advantage for one of the designs in the form of cooling which will be discussed in the Final Design section of this Report.
3.2.5. Elevation
Our brake system design must function within an elevation range of 3000 feet below sea level to 70,000 feet above sea level. This will simulate the broad application of the braking system as well as the operable elevations of the generators. We cannot completely neglect any effect the elevation will have and have considered the effect of elevation with respect to our final design.
3.2.6. Pressure
The pressure range we have considered in our Final Design will work within 0.75 to 1 atmosphere. The pressure range will also take into account the elevation change as well as any differential pressure between the pressure due to elevation and the pressure in which the generator creates.
3.3. Operational Conditions
3.3.1. Angular Velocity
We must design a gracing system that will operate at a minimum angular velocity of 7,200 rotations per minute and a maximum angular velocity of 28,000 rotations per minute. This constraint will have an effect on each of the concepts in its own way and was a major factor in determining a final design. The Final Design section will discuss how the range of angular velocity will affect the Final Design
3.3.2. Power Source
Our design will operate with a limited power source of 28 volts DC. This constraint operates with the power supply allowed by the generator. On top of operation at this power input we must develop a test rig that simulates the power supply.
3.4. Functional Conditions
3.4.1. Duty Cycle
Our braking mechanism should not deteriorate over time. We also need it to last for the life of the generator. Due to the fact that this activation system must act when triggered we cannot have any part fail due to deterioration.
3.4.2. Design Envelop
Our Braking system design must fit into a design envelop of a 5 inch Diameter and a 1.25 inch width. The free area of our disk will also depend on the drive shaft diameter which will have an affect on one of our proposed design concepts.
3.4.3. Hazardous Material
We may not have any hazardous material for unspecified reasons stated by Honeywell. Fortunately for our Proposed Designs, we will not require the use of any hazardous materials.
3.4.4. Reliability
Our final design and product must have a reliability of 99% operational readiness. Our product must work when triggered. Late activation or no activation may cause irreversible damage to the gearbox, generator, or both. It has to work with NO uncertainty.
3.5. Budget
We have been given a budget of $2,000. We may not go over that amount and no additional funding will be allotted.
3.6. Test Rig Properties (accurate simulation of actual application)
3.6.1. Weight
Our test rig needs to be portable to allow the demonstration at Design Day as well as for presentation to Honeywell. If it is too heavy we will not have the ability to transport the test rig in order to demonstrate our product.
3.6.2. Circuitry
The test rig must provide a power of 28 volts to accurately simulate the activation of our braking system during operation on the generator.
3.6.3. Housing
The test rig needs to accurately model the design envelop established in the Functional Conditions.
3.6.4. Motor Output
The motor on the test rig must supply a sufficient amount of torque at the velocity needed to simulate angular velocity of the actual generator.
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this girl has been busy with various enterprise endeavors ever because moving to florida including her very personal dating site
hello i m doing project on circular eddy current
cn any1 assist me whether i have to give ac supply or dc supply to electromagnet?
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i want eddy current brakes full report plz send to shanumaha09[at]gmail.com
i want eddy current brakes seminar full report send to shanumaha09[at]gmail.com
Posts: 7,939
Threads: 421
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what should be the weight and diameter of plate used in eddy current breake system, moreover tell me about the power of electromagnets used.
i need it please send mi complete report of eddy current break
