PDR Presentation with Updated Requirements Slides.pptx
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Transcript of PDR Presentation with Updated Requirements Slides.pptx
The University of Arizona Hyperloop Pod Compressor & Air
Bearing System Design
DLN 8/24/15
Team Description & ObjectiveThe University of Arizona Hyperloop Team is a motivated group of three graduate and twenty undergraduate students who have an interest in the Hyperloop concept. Our team represents an engineering club on campus whose aim is to develop research and technical skills while being students.
Our team’s objective is to study and optimize the compressor and air bearing systems for a hyperloop pod design. We plan on presenting our design at design weekend but we do not intend to compete with a full pod design.
Team Members:John Mangels, Irene Moreno, Philip Ciuffetelli, Jacob Grendahl, Kevin Sherwood, Mark Ernst, Rohan Mehta, Tristan Roberts, Aaron Kilgallon, Corey Allen Colbert, Jeremy Harrington, Mandy Olmut, Ryan Jensen, James Nguyen, Namrah Habib, Jacob Pavek, Patrick Portier, Harshad Kalyankar, Ryan Petronella, Jonathan Heinkel, Joel Mueting, Sean Gellenbeck, Ben Kaufman
Faculty Advisor:Dr. Cho Lik ChanAerospace and Mechanical Engineering
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DLN 8/24/15
System Level RequirementsName Description
Verification MethodAnalysis Inspection
Pod Constraint Pod mass shall not exceed 11,000 lbm X X
Test Track Interface Pod shall fit within the cross-sectional area of the test track X X
Operational Pod shall be moveable at low speeds when not in operation X
Test Track Interface Pod shall utilize Operational Propulsion Interface X
Operational Pod shall be able to come to a complete stop by use of a braking system X
Operational Pod shall travel along the track in a smooth motion without colliding into the center rail. X
Operational Pod shall be able to travel at Mach 0.3 without inducing a syringe effect X X
Operational Pod shall be able to levitate using air bearings between the end of the acceleration phase and the beginning of the braking maneuver X X
Pod Constraint Pod shall be powered by an onboard power system X
Operational Pod shall be able to operate with an ambient tube pressure between 0.02 - 14.7 psi X X
Power Constraint Compressor and bearing support subsystems shall not exceed 1082.82 HP of onboard power X X
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DLN 8/24/15
Subsystem Level RequirementsSubsystem Description Verification Method
Analysis Inspection
Bearings Air bearing system shall interface with the test track according to the Hyperloop Tube Specification Document X
Bearings Air bearings shall levitate the pod before the completion of 800 ft acceleration phase X
Bearings Wheels shall support the pod during initial acceleration X X
Bearings Bearings subsystem weight shall not exceed 3700 lbm. X
Bearings Pod shall smoothly transition from wheeled bearings to air bearings during acceleration phase X
Compressor Compressor shall intake air moving between 0 and 334 ft/s X
Compressor Compressor shall supply air pressurized to 3.34 psi for the air bearing subsystem X X
Compressor Compressor diameter shall not exceed 70% of tube diameter X
Compressor Compressor subsystem weight shall not exceed 4700 lbm X
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*Demonstrations and test verification methods were not considered because no physical pod is being built
Air Bearing & Suspension System
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Concept 1
Operation < 100 MPH
• Pod levitated according to wheel requirements• Air bearings float• Hydraulic system activated at 100 MPH
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6
45
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(1)Nose (2)Hydraulic actuators (3)Pod (4)Air bearing platform (5)Wheel (6)Ground
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Concept 1
ConditionNormal Operation > 100 MPH
• Hydraulic actuators activated• Wheels are retracted• Air bearings fixed• Pod levitated according to air bearing
requirements
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6
4 5
12
(1)Nose (2)Hydraulic actuators (3)Pod (4)Air bearing platform (5)Wheel (6)Ground
ConditionCompressor Failure
● Air bearings fed from air tank● Pod slows to safe wheel speed● Wheels extend● Pod levitated according to wheel requirements
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Concept 2 (Selected Design)
Operation < 100 MPH
• Pod levitated according to wheel requirements• Air bearings float• Hydraulic system activated at 100 MPH
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3
6
4 5
1
(1)Nose (2)Hydraulic actuators (3)Pod (4)Air bearing platform (5)Wheel (6)Ground
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ConditionNormal operation > 100 MPH
• Hydraulic actuators activated• Air bearings are extended• Wheels float • Pod levitated according to air bearing
requirements
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3
6
4
2
5
(1)Nose (2)Hydraulic actuators (3)Pod (4)Air bearing platform (5)Wheel (6)Ground
ConditionCompressor failure
● Air bearings fed from air tank● Pod slows to safe wheel speed● Air bearings retract● Pod levitated according to wheel requirements
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Concept 2 (Selected Design)
Compressor
Wheels
Air Tank
Air Bearing
Air Bearing Platform
LegendAirPhysical Connection
Pushrod Suspension
Pod Frame
Cabin/Thrust
Hydraulic Suspension
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Concept 2 Architecture (Selected Design)
Trade Studies Air Bearings Linear Actuators Wheels
Trade Circular Ski Hydraulic Pneumatic Solid Pneumatic
Pros -Well Understood Concept-Simplified Flow Analysis -Symmetric-Requires One Orifice
-Utilizes All Available Area-Ideally More Even Pressure Profile
-Durability -Proven Technology-Quick Reaction-Precise Control
-No Associated Fluids-Light -Clean-Small Profile
-Not Concerned With Deflating-Maintenance Free
-Low Maintenance Cost -Light weight-Non flammable gas-Higher Capacity
Cons -Unused Available Bearing Area Due To Geometry
-Requires Numerous Inlet Orifice
-No Available Designs
-Introduces fluid to the system-Large Profile-Requires Fluid Reservoir
-Limited Output Force-Internal Pressure
Fluctuations-High Cost
-High Inertia-Heavy-High Replacement Cost
-Routine PressureChecks
Selected Design
Circular Single Orifice Fed Hydraulic Linear Actuators Nitrogen Filled Rubber Wheels
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Compressed Air TankAssumption:No pressure loss upstream of the jet
Main Air Tank:
Pressure Needed: 3.34 psiMass Flow Rate from the tank: 1.87 lb/s
Approximate stored air density: 0.161 lb/ft3● Based on a stored air temperature of 557 K (543 F)
Approximate Volume needed: 20 ft3● Used to only store some air● Mostly used to divert air to where it is needed
Material: Aluminium 6061● Density: 168.56 lb/ft3● Approximate Thickness: 0.20 in - 0.23 in
Secondary Tank:● Smaller● Highly Pressurized● Used only in Emergencies (compressor failure) to provide airflow
needed to keep the pod elevated and supply passenger compartment with air
Emergency Response
Air Tank Cabin/Thrust
Air Bearings
Pressure - 3.34 psiMass flow - 0.1984 lb/s
Divert air to the bearings for the duration of emergency deceleration
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Secondary Tank
Pod to damper attachment point
Air bearing to damper attachment point
Spring
Piston guide cylinder (hydraulic fluid contained here)
Damper piston
Damper piston guide
Hydraulic fluid line connections
Hydraulic System Components
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Air bearing to damper attachment point
Hollow chamber for air bearing feed tubes
Circular air bearing
Compressor Subsystem
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Power
Tubing
Design Concept 1Legend
Data
Bridged Power
Thrust
Axial Compressor
Storage Tank
Air Bearings
Mechanical Connection
Processor
Control System
Power
Suspension
Motor
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Power
Tubing
Design Concept 2 (Selected Design)
Legend
Data
Bridged Power
Mechanical Connection
Axial Compressor 1Low Pressure
Axial Compressor 2High Pressure
Motor 1 Motor 2
ControlSystem
Processor
Storage Tank
Air Bearings
Suspension
Thrust
Power16
Trade Studies-CompressorTradeoff Matrix
Trade Single Axial Compressor System Two Axial Compressor System
Pros • Simple 1 motor system • Uses less power• Basics compressor• Simplistic design and easier to model
• Can manipulate and change the compressor pressure ratio between the 2 stages
• High compression compared to initial conditions due to the second stage
Cons • Limited rpm movement for the same compressor ratio
• Low compression system• Less efficient
• Two drive shafts and two motors therefore higher power
• High intensity design harder to model
Selected Design Two Axial Compressor System (Design Concept 2)
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DLN 8/24/15
Materials SelectionMaterial Price ($/lb) Density
(lb/in^3)Tensile Strength (psi)
Yield Strength (psi)
Fracture Toughness (psi*in^0.5)
Fatigue Strength (psi)
Max Service Temp (deg F)
Melt Point (deg F)
Stainless Steel 2.67-2.94 0.275-0.293 6.96e4-3.25e5 2.47e4-1.45e5 5.64e4-1.37e5 2.54e4-1.09e5 1380-1510 2510-2640
Nickel-based Superalloy
9.48-10.43 0.28-0.313 5.8e4-3.05e5 4.35e4-2.76e5 5.29e4-1.0e5 1.96e4-1.31e5 1650-2190 2330-2580
Titanium alloys 10.07-11.11 0.159-0.173 1.16e5-2.1e5 1.09e5-1.74e5 5.01e4-6.37e4 8.54e4-8.95e4 842-932 2690-3060
Stainless Steel Nickel Based Superalloy Titanium Alloys
Pros ● Cheap● Resistant to corrosion● Protective surface layer
chromium oxide
● Used for corrosion protection
● Used for high temperature resistance (1832 °F)
● High melting point● High Strength● Good formability
● Excellent Corrosion Resistance● High specific strength● Solid Solution Strengthening ● Light ● Resistant to moving
Cons ● Cannot be strengthened with heat treatment
● Smaller tensile strength and fatigue strength
● Expensive ● High density implies
greater mass
● Expensive ● Low max workable temperature ● Not applicable for rotors
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DLN 8/24/15
Material Selection
• Materials for High Performance Compressor Blades• Need stable microstructure • Want material that can be directionally solidified or want to be able to use
a single crystal for each turbine blade • Best choice material: Nickel Based Superalloy
• Materials for Stators and Shell • High specific strength • Want rigid material that is resistant to moving• Best choice material: Titanium Alloys
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DLN 8/24/15
Compressor Modeling•All compressor modeling has been done using Laux-C
•Models only design concept #1•Limited by:
•Pressure range < 7.35 psi•Mass flow rate < 110 lb/s•Can’t set constant area of compressor
•Simulations have good theoretical accuracy for results
•We want to model the compressor with a specific area and be able to change the blade angle and rotational speed to create a better compression
•Switch to modeling the compressor in SolidWorks & ANSYS
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DLN 8/24/15
Compressor Model using SolidWorks
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Estimate Design Dimensions
Tube Pressure 0.105 psi
Pod Cross-Sectional Area 8.61 ft2
Diffuser Entrance Cross-Section (non-functional diffuser chosen to replicate design needed for full-scale model, i.e. the model can be up-sized)
7.76 ft2
Compressor Mass-Flow Rate 1.87 lbf/s
Mass Estimate of Compressor 1600.5 lbm
Item No. Material Description Quantity Total Mass (lbm)1 1060 Al Alloy Circular Air Bearing 15 in diameter 20 33.22 6061 Al Alloy Air Bearing Platform 15 in x 84 in 4 705.723 6061 Al Alloy Hydraulic system 4 165.044 AISI 4130 Steel Wheel System 4 176.88
Air bearings/Suspension:
Compressor/Pod Design:
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Max Pod Velocity 0.3 Mach
Exhaust Velocity 3.5 Mach
Exhaust Mass Flow Rate 0.77 lbf/s
Exhaust Throat Area 0.0116 ft2
Exhaust Nozzle Area 0.07878 ft2
Exhaust Thrust Produced 139.9 lbf
Estimated Minimum Pod Mass 2681.34 lbm
Concept 2 Pod Design
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Nominal Operations:Speed: 0.3 MachDrag force: 107.14 lbfCompensated by exhaust thrust of velocity magnitude 3.5 Mach
Braking System:System design is compatible with H2W technologies Linear MagnetBrakes and will use this technology as a means of deceleration.
Kantrowitz Limit: Compressor Failure
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Contingency Operations:Drag Force: 543.8 lbfDeceleration 2.6E-2 ft/s2 for a 2681.5 lbm podTime to reach < 100 mph: 379.2 secondsDeceleration Distance: 59110 feet
● Need to implement linear magnetic brakes to provide sufficient deceleration
● Effect of choked flow shock waves must be analyzed for safety
Table of Analysis
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Based on requirements, verifications, and sub-system interfaces
Requirement Model Tool
Bearing Pressure Profiles Numerical ANSYS FLUENT
Bearing Mass Flow Rate Numerical MATLAB
Air Bearing System Solid SolidWorks
Hydraulic System Solid SolidWorks
Wheel System Solid SolidWorks
Emergency Wheel Spin Numerical Excel
Pod Nose Profile Numerical ANSYS FLUENT
Compressor Model Solid SolidWorks
Compressor Pressure Model Numerical ANSYS FLUENT
Total Compressor Design Numerical LUAX-C and ANSYS FLUENT
Shock Wave / Acoustic Analysis Numerical ANSYS FLUENT
Risks Identified (R1-R6)
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Label System Failure Possible Solution(s) Risk Matrix Rating
R1
Hydraulic Suspension
Suspension won't come down/jammed upon reaching reasonable speeds for air bearings.
Recall the pod for inspection. Minor/Moderate & Rare
R2Suspension locked in the "down" position.
Slow the pod down using braking mechanism and have the pod attempt to slow down enough to where it can safely glide on the air bearings with little to no damage to the parts. Fix upon arrival.
Moderate & Rare
R3
Wheels & Wheel Suspension
Broken spring, rocker, damper, torsion bar, etc.
General maintenance inspections Insignificant & Rare
R4Broken spring, rocker, damper, torsion bar etc. during transit
There should be multiple wheels so not much concern during transit. If this occurs during the beginning of the trip recall the pod and fix. At the end of the trip, decelerate to slower speeds than what would be normal to pull the air bearings up and gently rest the pod on the remaining wheels. Fix at the end of trip. Make sure that max weight isn't reached.
Minor & Rare
R5Wheels/tires worn during transit
Decelerate to slower speeds. Minor and Unlikely
R6 Wheels/tires worn General maintenance inspections Insignificant & Rare
Risks Identified (R7-R13)
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Label System Failure Possible Solution(s) Risk Matrix Rating
R7
Wheel Motor(s)
Motor(s) failure (won't work, turn on, etc.)General maintenance inspections. Before take off, if not working, delay the schedule to fix.
Minor & Unlikely
R8 Motor(s) failure during transitSlow pod down enough to where the weight can be put on wheels without them being turned/rotated beforehand.
Minor & Unlikely
R9
Air Bearings
Damage to air bearings during transitMaintenance/repair/replacement after pod comes to a stop at the end.
Moderate & Unlikely
R10Loss of pressure to one or multiple bearings in transit (duct failure or clogged orifice)
Decelerate to slower speeds, retract air bearings to have pod on wheels to reduce damage to the bearings. Try and figure out issue, otherwise roll on wheels to end of trip.
Moderate & Unlikely
R11 Loss of pressure to all bearings
Pod falls on bearings; bearings will be coated with material with a low coefficient of friction; this will allow the pod slide without causing catastrophic damage
Major & Rare
R12 Compressor Complete compressor failureCompressed air tank will supply to the bearings with air until the pod can be slowed to acceptable wheel deployment speed
Major & Rare
Risks Identified (R14-R17)
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No use of hazardous materials in design
Label System Failure Possible Solution(s) Risk Matrix Rating
R13
Compressor
Complete rotor failureRegular metallographic examinationsCompressor Braking mechanism
Minor & Unlikely
R14 Duct to storage tank failureAuxiliary duct system. High strength/reliability ductsRegular inspection of ductwork
Insignificant & Unlikely
R15
Material Failure:• Low/High cycle and thermal fatigue• Environmental exposure and foreign
object debris • Excessive tensile load on blade tip
Regular inspection of high stress partsHigh performance materials Moderate & Rare
R16
Blade Failure• High centripetal forces• Gas flow induced steady state stress• Foreign object debris• Thermal stress e.g: nonuniform
temperature distribution
Highly accurate, symmetrical blade designHigh performance material compositionRegular blade inspectionPerformance inconsistencies require inspection
Moderate & Unlikely
R17 Entire Pod Weight Overload Check weight before takeoff.Insignificant/Minor &
Rare
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R5 R7R8
R9
R1R3R6 R4
R17
R2R15
R10
R11R12
R16
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R13R14
Next StepsAir Bearings & Suspension Subsystem:
•Modeling of Nose Cone Profile•Reducing weight required to be lifted by air bearings•Flow analysis for air bearing pressure distribution•Create full model of pod assembly
- Optimize design using openMDAO•Stress analysis for suspension components
Compressor Subsystem:• Develop a duct system
•Account for pressure loss due to friction•Account for temperature increase due to friction
• Model the compressor with a better modeling tool such as ANSYS• Verify and clarify tolerance ranges and dimensions of compressor• Model bypass stream of air to cool compressor to prevent overheating of system
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