P14651: Drop Tower for Microgravity Simulation

1. P14651: Drop Tower for Microgravity Simulation Adam Hertzlin Dustin Bordonaro Jake Gray Santiago Murcia Yoem Clara

2. Week 3 Review – Open Items • How many pumps are needed? • Benchmark NASA Drop Tower components • Research designs to hold vacuum pressure • Determine location for Drop Tower • Create working design w/o cost considerations • Meet with Deans • Meet with Grad Students

3. Agenda • Background • Problem Statement • Stakeholders • Customer Requirements • Engineering Requirements • System Analysis • Requirements Matrix • Benchmarked Components • Functional Analysis • Concept and Architecture Development • Engineering Analysis • Risk Assessment • Test Plan • New Focus as of Sep 30

4. BACKGROUND

5. Problem Statement • Current State • Ex) NASA Space Flight Center • 100 meter – 4.5 sec drop • Ultimate Pressure: 10-9 Torr • Limited Visibility • Desired State • P14651 Drop Tower • 9-12 meter ~ 1.5 sec drop • 15-30cm diameter tube • Object visible during drop • Continuous Lift / Release System • Appropriate pump(s) for required pressure • Educational and fun for all ages

6. Problem Statement Cont’d • Project Goals: • Fast Cycle Time • Cost efficient • Aesthetically pleasing • Precision in measurements • (1% estimation of standard gravity) • Adaptability for multiple / future uses • Minimal vacuum loss • Constraints: • Location and design approval from the Dean(s). • Material availability/size (ex. tube, pump) • Budget $3,000

7. Additional Deliverables • User’s Guide for operation • Designed Lab Experiments: • Determine gravity in the vacuum within 1% error • Compare drag at different pressures and drag vs. acceleration • Additional vacuum related experiments

8. Project Stakeholders MSD Team Dr. Kandlikar RIT Graduate and Undergraduate Students Middle School Students RIT Faculty RIT Prospective Students RIT College Dean(s) Middle School Teachers

9. Customer Needs

10. Engineering Specifications

11. SYSTEM ANALYSIS

12. Requirements Matrix

13. Benchmarked Components

14. Benchmarked Components Cont’d

15. Functional Decomposition

20. Morph Chart

21. Morph Chart

22. CONCEPT & ARCHITECTURE DEVELOPMENT

23. Early Concept Draft

24. Pugh’s Matrix Component Concepts Baseline Ideal Cheap Feasible Random

26. Capsule Designs

27. Selected Concept

28. Selected Concept: Architecture • Piping • Main Tower Piping • Tee Shape Base w/ Removable Cap • Tee Shaped Couplings • Standard Couplings • Base Flange for Tower Support • Sealing Cap • Valve / Clamps • Release Level Clamps • Pressurizing Valve • Manual Isolation Valves • Sensors • Laser Sensors • Thermocouple Sensor • Multifunctional DAQ • Pump • Vacuum Pump • Digital Vacuum Gage • Fittings • Catch / Release • Release Platform • Polystyrene Beads for Deceleration • Other • Pulley System • Basket

29. Selected Concept: Theory of Operation

30. Selected Concept: Approximate Cost

31. Engineering Analysis

32. Engineering Analysis • Gravity Calculations • % Error in gravity calculations • Drag Force Calculations • Tube Conductance • Pump down (evacuation) time • Ultimate Pressure Required • Critical Pressure for Tube Dimensions

33. Gravity Calculation with 1% Error • Constant Acceleration Equations • Assumes no air resistance / perfect vacuum • , where x is position and t is time • Assumes perfect Vacuum

34. Free Body Diagram of Object • Force Balance • At Terminal Velocity, acceleration = 0 • At Vacuum Pressure, drag force = 0 • , where a is downward (negative)

35. Drag Force (Air Resistance) • FD = Drag Force • ρ = Air Density • V = Velocity of Object • CD = Drag Coefficient (Fudge Factor) • A = Projected Area of Object • P = Air Pressure (Pa) • R = Specific Gas Constant = 287.05 J/kg*K • T = Air Temperature = 21°C = 274K

36. Conductance • The flow of air in a tube, at constant temperature, is dependent on the pressure drop as well as the cross sectional geometry. • , (Viscous Flow 760Torr  1Torr) • , (Molecular Flow 1Torr  Vacuum) • C = Conductance (liters/sec) • F1 = Viscous Flow Scale Factor = 2950 • F2 = Molecular Flow Scale Factor = 78 • D = Pipe Diameter (in) • L = Pipe Length (in)

37. Effective Pump Speed • C = Conductance (cfm) • We assume that for Viscous Flow, = • = Given Pump Speed (cfm) • = Effective Pump Speed for Tube Dimensions • Example: Single 6” x 30’ Tube • (assumed)

38. Evacuation Time VP10D CPS Vacuum Pump 2 Stage Rotary Pump 15 micron Ultimate Vacuum Pump Speed – 10 cfm Price: $417.89 • = 760 Torr • = 1 Torr • = Final Pressure • Example: Single 6” x 30’ Tube • = 15 micron or 0.015 Torr • (assumed)

39. Pressure Requirement • The pressure required for accurate gravity calculations can be calculated using the previous equations and the following assumptions: • Max Tube Height = 12 meters • Constant Acceleration • Max Object Mass = 2.27 kg • Max Drag Coefficient = 2.0 • Max Projected Area = Cross Sectional Area for 10 cm Diameter • Allowable Error in Gravity due to Pressure = 0.01% • These assumptions yield an allowable pressure of 103 Pa (0.773 Torr or 773 microns)

40. Risk Assessment

43. Top Locations: #1 selection Thomas Gosnell Hall

44. Thomas Gosnell Hall – Floor plan Available Height: 1- 46’ 2 - 43’ 3 – 39’

45. Top Locations: #2 James E. Gleason Hall

46. James E. Gleason Hall – Floor plan

47. Top Locations: #3 Institute Hall

48. Institute hall – floor plan North Door Stairs Available Height: 77’-6”

49. Top Locations: #4 Golisano Institute of Sustainability

50. Golisano Institute of Sustainability – Floor plan