1. P11221 - Noise Reduction for Internal Combustion Engines
Team Leader: Christopher Morehouse
Mechanical Engineers: - Julie Maier
- Caroline Bills
- Ted Zachwieja
Faculty Advisor:
Ed Hanzlik
Customer:
Dr. Alan Nye

2. Agenda Problem Overview Project Objectives Customers and Users
Project Flow Chart & Plan
Engine Model Overview
Design Options
Design Feasibility
Next Steps
Questions & Discussions

3. Background Noise abatement - growing field
Formula SAE Sound Constraints
Conventional Methods Reduce Performance
No RIT Background in this Field
Multiple Applications Possible
Customer: Dr. Nye
Users: Formula SAE Team
EE Team

4. Project Scope Investigate physics of sound generation and transmission
Identify and locate major noise contributors in ICE
Analyze and model noise generation of ICE
Propose design for noise reduction mechanism
Provide background to EE team for parallel ANC project
Provide noise reduction demonstrator for Spring 2011 ImagineRIT

5. Project Deliverables Engine Sound Model ANC System Constraints
Demonstrator for ImagineRIT

6. Project Overview

7. Project Breakdown

8. Detailed Project Breakdown

9. Customer Needs

10. Engineering Specifications

11. Relationship Diagram ES 1 Reduce noise level
ES 4 Passes B of the SAE Formula rules
ES 7 Component Costs
ES 12 Change in Engine Max Power

12. The Plan

13. The Plan

14. Risk Assessment

15. Risk Assessment

16. Risk Assessment

17. Research & Benchmarking

18. Sound is Pressure

19. How We Measure Sound Digital Signal Processing Decibel Meters
Sound Pressure Indicators

20. IC Engine Sources
Pressure Waves

21. Engine Model

22. MECHANICAL DESIGN OPTIONS

23. Current Design
Glass Pack
Low Flow Restriction
Low Noise Attenuation

24. Unpacked Concentric Tube Resonators
Design #1: Single-pass
Design #2: Multi-pass
Passive

25. Design #1: Single-pass

26. Design #2: Multi-pass

27. Packed Concentric Tubes
Design #3: Metal Foam
Design #4: Full Length of the Exhaust System
Design #5: Rock Wool and Stainless Steel Wool

28. Designs #3 & #4: Metal Foams

29. Foams Permeability Pore Size Level of Reticulation Absorption Area
Length
Curves
Thickness
Scott Acoustical Laboratories

30. Foams

31. Optimal Foam Structure
Industrial Noise Control Handbook. Cheremisinoff and Cheremisinoff

32. Absorption Area
Industrial Noise Control Handbook. Cheremisinoff and Cheremisinoff

33. Metal Foams Available in a variety of densities
Available in a variety of pore sizes
ERG Duocel
Test kit en route
Aluminum
Copper
Silicon Carbide
Reticulated Vitreous Carbon (RVC)

34. ERG Duocel Metal Foams
ERGaerospace.com

35. Design #5: Rock Wool A fibrous insulation made from basalt
Custom Muffler and Auto Repair, LA
Cone Engineering, Inc., CA
MagnaFlow Exhaust

36. Rock Wool

37. Design #7: Exhaust Silencer Insert
Applied to exhaust tip
Reflects Sound Waves back into exhaust stream

38. Design #8: Active Single-pass

39. Design #9: Active Multi-pass

40. ELECTRICAL DESIGN OPTION

41. Design #10: Active Noise Cancellation (ANC)
This generates more sound by the adding of two waves.

42. ANC continued
Introducing a wave 180 degrees out of phase of the targeted noise being cancelled.

43. Dominating noise comes from the muffler
How ANC Applies to Cars
Three Major components of sound generation occur in a car
Dominating noise comes from the muffler

44. Feed Forward Control

45. Feedback Control

46. Installation Options

47. CONCEPT SELECTION

48. List of Design Options Current Glass Pack*
Unpacked Concentric Tube Resonator
Multi-pass Resonator
Metal Foam*
Entire Length of Exhaust System Wrapped
Lava Rock/Rockwool and Stainless Steel Wool*
Multiple Exhaust Pipes (Combination)
End Cap Silencer (Combination)
ANC
Variable Length Resonator - Single Pass
Variable Length Resonator - Multiple Pass

49. Criterion List

50. Simple Concept Matrix

51. Simple Concept Matrix (cont.)

52. Simple Concept Matrix (cont.)

53. Weighted Concept Screening Matrix

54. Weighted Concept Screening Matrix

55. Weighted Concept Screening Matrix

56. Results

57. Resulting Design Options
Unpacked Concentric Tube Resonator
Packed Concentric Tube:
Metal Foam
Lava Rock/Rockwool and Stainless Steel Wool
Variable Length Resonator - Single Pass
ANC
(End Cap Silencer, Multiple Exhaust Pipes)

58. Critical Action Items Action Item Goal No Later Than
Design Commitment Oct. 15
Data Collection (CB) Oct. 14 Oct. 21
Engine Model (CM) Oct. 18 Oct. 25
Design Resonator (JM) Oct. 22 Oct. 25
Detailed BOM & Budget (CB) Oct. 29
Detailed ANC Component Requirements (TZ) Oct. 22 Oct. 29
Detailed ANC Layout & Mounting Schematic (TZ) Oct. 29 Nov. 1

59. Sources http://www.eastsidemufflers.com/mufflers.htm Picture Sources
Slide 1
Slide 2
Slide 5
Slide 35