directive train horn demonstration system performance
DESCRIPTION
Directive Train Horn Demonstration System Performance. Paul Burgé, INCE BD.CERT, URS Corporation Parke Rhoads, Acentech Incorporated. The Train Horn Problem : Train horn noise is typically the loudest and most annoying component of train noise in areas near grade crossings - PowerPoint PPT PresentationTRANSCRIPT
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Directive Train Horn Demonstration System PerformancePaul Burgé, INCE BD.CERT, URS Corporation
Parke Rhoads, Acentech Incorporated
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
The Train Horn Problem: Train horn noise is typically the loudest and most
annoying component of train noise in areas near grade crossings
Train horn soundings are generally required at most highway/rail grade crossings
Most train horns are generally omni directional, casting acoustical energy in all directions without regard to where the signal is needed or unwanted.
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Train Horn Directionality
Source: Raposa and Fleming, IWRN 2001
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Train Horn Noise Solutions: More grade separations Quad gate crossings Median barriers One way streets Wayside horns Directional train horns
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Directional Train Horn Concept:
Source: Coate, Kern and Africk, IWRN 2001
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Directional Train Horn Benefits:
•Fleet horn upgrades would provide noise reduction benefit at all grade crossings where horns are currently sounded
•No ambiguity or habituation (relative to wayside horn)
•Would work for virtually all grade crossing configurations
•Retains traditional train horn warning signal information with regard to train’s relative proximity and direction
•Could be implemented in a cost efficient manner
•Looks “cool”
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Cancellation(destructive interference)
Summation(constructive interference)
Acoustic Line Array:–
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Direction Train Horn Demonstration Opportunity: Contractors URS and Acentech were asked by The Los Angeles County Metropolitan Transit Authority (MTA) to develop a unit to demonstrate whether a directive horn could successfully reduce crossing noise levels noise levels on recently opened MTA Gold Line light rail transit line under an existing contract
Typical MTA Gold Line
grade crossing
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Demonstration System Project Approach
• Evaluate existing warning system
• Design system for improved directivity
• Static laboratory tests and refinement
• Limited static and dynamic field test and refinement (road vehicle)
• Full static and dynamic field test and evaluation (rail vehicle)
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
MTA Gold Line LRT Vehicle
Existing Train Horn Directivity (dBA)
40
50
60
70
80
90
1000
1530
45
60
75
90
105
120
135
150165
180-165
-150
-135
-120
-105
-90
-75
-60
-45
-30-15
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Proposed train mounted array horn (artist’s conception)
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Directional array demo system and block diagram
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Truck mounted horn array
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
measurement positionsposition distance angle
1 50 02 50 153 50 304 50 455 50 606 50 757 50 908 50 1059 50 12010 50 13511 50 -13512 50 -9013 50 -4514 100 -9015 100 016 100 90
50 ft.
100 ft.
12
34
5
6
7
8
9
1011
12
13
14
15
16
Directivity Test setup
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Measured Warning System Directivity
40
50
60
70
80
90
1000
1530
45
60
75
90
105
120
135
Traditional Horn
MTA Horn
Array
Array and MTA horn levels at 50 feetTraditional horn (Leslie RS-3L) levels at 100 feet
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Monitor LocationsMon. # Set up A Location Set up B LocationM1 Middle of run, 25' back Middle of run, 25' backM2 End of run, 25' back 50' past run, 25' backM3 Middle of run, 50' back Start of run, 50' backM4 End of run, 50' back 50' past run, 50' backM5 Middle of run, 100' back 50' before run, 50' backM6 End of run, 100' back 50' Past run, 100' back
direction of travel sounding region
A1/B1
A3
A5
A2
A4
A6
B2
B4
B6
B3 B5
N S
50 feet
Dynamic pass-by test setup
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Dynamic pass-by test setup
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Horn Vs. Array (quacker) Horn Array Reductionrec. loc. description Ldn %HA Ldn %HA Ldn %HAA1/B1 Middle of run, 25 ft. back 67.9 20.4 55.7 4.5 12.2 15.9A2 End of run, 25 ft. back 69.0 22.6 55.4 4.3 13.6 18.3A3 Middle of run, 50 ft. back 58.7 7.1 48.3 0.7 10.4 6.4A4 End of run, 50 ft. back 62.4 11.5 50.1 1.3 12.3 10.2A5 Middle of run, 100 ft. back 53.2 2.8 43.3 0.0 9.9 2.8A6 End of run, 100 ft. back 56.3 5.0 45.7 0.0 10.6 5.0B2 50 ft. past run, 25 ft. back 65.7 16.5 54.2 3.4 11.5 13.0B3 Start of run, 50 ft. back 54.5 3.6 44.1 0.0 10.4 3.6B4 50 ft. past run, 50 ft. back 63.4 12.9 50.4 1.4 13.0 11.4B5 50 ft. before run, 50 ft. back 47.0 0.0 42.7 0.0 4.3 0.0B6 50 ft. past run, 100 ft. back 57.5 6.0 46.9 0.0 10.6 6.0
Community Noise Analysis
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Future Design Refinements
• Varying Number or Directivity of Array Elements
• Curved Array Geometry
• Non-uniform Array Element Spacing
• Electronic Delay and Phasing
• Higher-order Gradient Array Configuration
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Optimal Warning System DirectivityWarning System Directivity (dBA)
40
50
60
70
80
90
1000
1530
45
60
75
90
105
120
135
Traditional Horn
MTA Horn
Array
Optimal
Array and MTA horn levels at 50 feetTraditional horn (Leslie RS-3L) levels at 100 feet
TRB ADC40 Noise and Vibration 2006 Summer Meeting
Acoustics and Noise and Control Services
Questions or
Comments