DNV GL Houston Technology Seminar 2016

Transcription

1 MARITIME DNV GL Houston Technology Seminar 2016 Noise and Vibration Yanran Wang DNV GL SAFER, SMARTER, GREENER

2 Agenda Introduction and Terminology Rules and Regulations Noise and Vibration Control Yanran Wang 2

3 Maritime Advisory in a nutshell Maritime Advisory Service We help clients to mobilise the full potential of their assets and operations. We offer technical and managementsupport and assist clients in managing risk through high value advisory services. Areas of Expertise Hydrodynamics Mechanical & Systems Engineering Structures Noise & Vibration Shipping Advisory Concept Advisory Safety, Risk & Reliability Lifecycle Management Facts Part of DNV GL Maritime ~300 highly skilled staff Offices in Norway, Germany, China, Singapore, USA, Japan and Australia Almost 100 services mobilizing the full potential of our client s assets and operations 5% of annual revenue invested into R&D Vast computational capacities 3

4 DNV GL Noise and Vibration Miami Oslo Hamburg Shanghai 4

5 DNV GL Noise and Vibration related Activities Classification: Comfort Class (COMF) Vibration Class (VIBR) Silent Class (SILENT) Advisory: Specification assistance Review of design Design stage analyses Verification measurements Troubleshooting measurements Vibration surveys 5

6 Island Performer - COMF-V(1) 6

7 Oasis of the Seas COMF-V(1) 7

8 Megayacht Azzam 8

9 James Cook SILENT(R) 9

10 Marbat- COMF-V(1) / VIBR 10

11 Rowan Viking 11

12 Seafox 5 12

13 Definitions and Terminology 13

14 What is vibration? Vibration is mechanical oscillation about an equilibrium point 14

15 How to define noise and vibration? Frequency 15

16 How to define the level of vibration? Velocity: v (mm/s) Displacement: y (mm) Acceleration: a (mm/s 2 ) y = v / ω a = v ω Where, ω = 2f f = vibration frequency (Hz) 16

17 How to define vibration? amplitude Project Name Velocity level, mm/s (peak) Frequency (Hz) File 19, V_max (>5 Hz) = 27.9 mm/s at 6.9 Hz - Amplitude: maximum value of sinusoidal quantity - Frequency spectrum: description of quantity as a function of frequency 17

18 How to define noise and vibration? From time signal to frequency spectrum 18

19 Vibration, definitions Natural frequency A frequency of free vibrations in a system Resonance A state of coincidence between frequency of applied excitation and system natural frequency Critical frequency A frequency at which resonance occurs Resonance Subcritical Supercritical 19

20 Vibration Mode Node Node Mode of vibration Characteristic pattern related to the number of nodes (e.g. 2-node mode etc., see figure) Mode shape The relative amplitude curve Node Position of vibratory rest Anti-node Position of vibratory maxima 20

21 What is noise? Transformer Hum Telephone Bandwidth TV-hum [Hz] Vibration Vibration Noise 21

22 Noise - definitions Low noise Sound pressure: Medium noise High noise Lowest audible sound: Pain threshold: appr. 20 x 10-6 Pa appr Pa 22

23 Definition of sound pressure level Sound Pressure Level: SPL = 20 log P Pref db P = Sound Pressure in Pascals [Pa] P ref = 20 x 10-6 [Pa] (airborne) 23

24 Noise Frequency Weighing 24

25 Typical noise levels How about your office 25

26 Hearing Damage Sound Level (85 db(a)), Time of exposure (8 h), Frequency content, Period of rest in quiet environment, Individual sensitivity Often the most common work related injury Reduced hearing ability, tinnitus, increased risks in a working environment 26

27 Regulatory Noise and Vibration Levels Maritime Industry 27

28 Rule and regulations Examples of existing/frequently used noise and vibration requirements for maritime industry Classification societies IMO ISO 28

29 Noise impacting passengers comfortable level onboard 29

30 Vibration impacting passengers comfortable level onboard 30

31 DNV GL Comfort Class DNV GL Comfort Class comprises a rating of Noise Vibration COMF-V(1-3) Indoor Climate COMF-C(1-3) 31

32 DNV GL Comfort Class Noise and Vibration limits Passenger ships, Passenger Accommodation Noise levels in db(a) Locations Comfort rating number (crn) Passenger top grade cabins Passenger cabins, standard Public spaces Open deck recreation 1) ) 5 db(a) relaxation in sports areas, passage ways and near ventilation inlets and outlets Passenger Ships Passenger Accommodation Frequency weighted r.m.s values in mm/s from 1 Hz to 80 Hz. Locations Comfort rating number (crn) Passenger, top grade cabins Passenger cabins, standard Public spaces Open deck recreation For passenger ships with comfort rating 1, no single frequency component within the frequency range 6.3 Hz to 12.5 Hz shall exceed 1 mm/s r.m.s (weighted). 32

33 Why Comfort Class for offshore vesselss? In 1999 a major oil company observed a considerable increase of undesired incidents

34 Comfort Class as part of SHE The incidents occurred during operation of supply, anchor handling and rescue vessels in the North Sea 34

35 Parameters resulting in discomfort and reduced sleep/rest quality At work onboard Off duty onboard Sea motions 24 % Vibrations 34 % Noise 22 % Sea motions 24 % Climate 22 % Noise 22 % Vibrations 17 % Climate 13 % Contaminated 8 % Others 5 % air Light 6 % Contaminated 2 % air Others 2 % Lys 0 % 35

36 DNV GL Comfort Class (1 st of January 2014) Locations Cargo ships, Crew Accommodation 1) Noise levels in db(a) Comfort rating number (crn) < GT GT Wheelhouse Radio room Crew cabins Crew public spaces Hospital Offices Machinery control rooms Open deck ) For working areas, navigation spaces, service spaces, machinery rooms and spaces not specified, the requirements of IMO MSC 337(91) Code on noise levels onboard ships apply. Cargo ships Crew Accommodation and working spaces Frequency weighted r.m.s values in mm/s from 1 Hz to 80 Hz. Locations Comfort rating number (crn) Cabins Mess/recreation rooms Offices Navigation bridge Control Rooms Work places For cargo ships with comfort rating 3, except for work spaces, no single frequency component within the frequency range 1.0 Hz to 8.0 Hz shall exceed 2.7 mm/s weighted r.m.s. 36

37 Comfort Class has positive impact on SHE performance 15 Reduced number of accidents after implementation of Comfort Class Today required on board all the major oil companies chartered service 12 vessels DNV GL

38 Well Intervention Vessel - COMF-V(1)C(1) 38

39 Cruise Vessel DNV Comfort Class 39

40 LNG Tanker- COMF-V(1)C(2) 40

41 Noise and vibration regulations and standards in maritime ISO Vibrations IMO - Noise 41

42 ISO Standard on Vibration Max repetitive values Max repetitive value= C F 2 r.m.s value Conversion factor to be multiplied with the measured value (1.8) Each single frequency component to be assessed separately 9 mm/s 4 mm/s Adverse comments probable Adverse comments not probable 42

43 Broadband Vibration Criteria ISO , Weighting Curve Factor Weighting Curce Hz 43

44 ISO Overall Vibration Criteria Values above which adverse comments are probable Values below which adverse comments are not probable Area Classification A B C mm/s 2 mm/s mm/s 2 mm/s mm/s 2 mm/s Note: The zone between upper and lower values reflects the shipboard vibration environment commonly experienced and accepted. Overall frequency-weighted RMS values from 1Hz to 80Hz given as guidance for the habitability of different areas on a ship. Classification A: Passenger cabins Classification B: Crew accommodation areas Classification C: Working areas 44

45 IMO resolution A.468 (XII) on Noise 1981 Recommended noise levels Only for transit condition Location IMO A.468 Work Spaces: - Machinery spaces (continuous manned) 90 - Machinery spaces (not continuous manned) Engine Control Room 75 - Workshops 85 - Non-specified work spaces 90 Navigation spaces - Wheelhouse, chart rooms and radar rooms 65 - Listening posts, incl nav. Bridge wings 75 - Radio rooms 60 Crew Accommodation Spaces - Cabins and hospital 60 - Mess rooms 65 - Recreation Rooms 65 - Gymnasium 65 - Open deck recreation 75 - Offices 65 Service spaces - Galleys (without food processing equipment in operation) 75 - Serveries and pantries 75 Normally unoccupied spaces - Spaces not specified 90 45

46 New IMO MSC Res.337(91) This Code is legally treated as a mandatory instrument under the SOLAS Convention. 46

47 New IMO MSC Res.337(91) Not applicable Applicable Applicable with stricter criteria GT < > GT < GT >

48 New IMO MSC Res.337(91) Not applicable vessels Dynamically supported craft High-speed craft Fishing vessels Pipe-laying barges Crane barges Mobile offshore drilling units Pleasure yachts not engaged in trade Ships of war and troopships Ships not propelled by mech. means Pile driving vessels Dredgers 48

49 New IMO MSC Res.337(91) Noise level limits Work spaces Designation of rooms and spaces Ship size 1,600 upto 10,000 GT 10,000 GT Machinery spaces Machinery control rooms Workshops other than those forming part of machinery spaces Non specified work spaces (other work areas) Navigation spaces Navigating bridge and chartrooms Look-out posts, incl. navigating bridge wings and windows Radio rooms (with radio equipment operating but not producing audio) Radar rooms Accommodation spaces Cabin and hospitals Messrooms Recreation rooms Open recreation areas (external recreation areas) Offices

50 New MSC Res.337(91) Conditions Transit condition At no less than 80% of MCR Thruster condition At no less than 40% of MCR 50

51 ABS HAB for Workboats 51

52 Regulatory Noise and Vibration Levels Offshore Units 52

53 Regulations Examples of existing/frequently used noise and vibration requirements for offshore installations Classification societies Company specific limits OTO British criteria and guidelines NORSOK Norwegian criteria and guidelines 53

54 UK OTO Noise criteria 54

55 UK OTO Vibration criteria ~0.4 mm/s peak 55

56 NORSOK S-002 Working Environment Noise Personnel Noise Exposure Area Noise Levels (total noise) Area Noise Levels (HVAC alone) Sound absorption in some areas Sound insulation between rooms Vibration Vertical & horizontal vibration of deck 56

57 Vibration limits - NORSOK Vibration limits based on ISO Based on a 12 hour working day Specified as acceleration in the frequency range 1 80 Hz Vertical and horizontal direction ~0.4 mm/s peak 57

58 Noise limits -NORSOK Strict regime compared to IMO Examples: Area IMO NORSOK Cabins 60 / (45 for MoU) Hospital 60 / (45 for MoU) Offices 65 / (50 for MoU) 58

59 DNV GL Offshore Comfort Class Background MoU owners and operators have requested DNV GL regulations or a class covering the working environment on board offshore facilities. References were frequently given to our Comfort Class for ships. NORSOK/UK OTO sometimes found to be difficult to understand for owners and yards. 59

60 DNV GL Offshore Comfort Class - Overview Covering the following (typical package defined as working environment): Noise Vibration Indoor Climate Illumination (NEW) 60

61 DNV GL-Human Comfort Standard Noise Level Limits Process and utility modules Drilling modules Accommodation spaces 61

62 DNV GL-Human Comfort Standard 62

63 ABS HAB for MODU 63

64 VIBRATION Class 64

65 Vibration could impact the structure fatigue

66 DNV GL Vibration Class -VIBR DNV GL Vibration Class gives vibration limits to machinery, equipment and structures 66

67 DNV Vibration Class - VIBR 67

68 DNV Vibration Class - VIBR 68

69 DNV Vibration Class - VIBR 69

70 Stavangerfjord- VIBR 70

71 Normand Arctic - VIBR 71

72 Ramform Titan - VIBR 72

73 VLCC Al Riqqa Reference to VIBR 73

74 SILENT Class 74

75 Underwater Sound Levels Ships underway Broadband source level (underwater db at 1 m) Source Broadband source level (underwater db at 1 m) Tug and barge 171 db Grey whale moans db Supply ship 181 db Bowhead whale tonals, moans, and song db Large tanker 186 db Humpback whale song db Photo source:

76 DNV GL Underwater Noise Notation SILENT Environmental DNV GL was the first class society published underwater noise notation DNV GL SILENT notation to alleviate environmental impact and ensure satisfactory operational performance

77 Port Metro Vancouver: EcoAction Program Receive Discounted Harbour Due Rates by Participating in EcoAction Program DNV GL Silent Environmental (E) notation will be included in the EcoAction program for The Gold Level recognition and 47% discount on Harbour Dues will be available for any qualified vessel transiting to the Port of Vancouver on January 1, 2017 and beyond.

78 Silent Sub-notation (R) Research Based on existing ICES 209, with a low frequency modification Extremely demanding Requires submarine technology db re. 1 X 10-6 Pa/m Frequency 11 kts free sailing 78

79 Silent Sub-notation (F) Fishery Fishery (F) db re. 1 X 10-6 Pa/m Frequency Heavy towing 79 DNV GL light search

80 Silent Sub-notation (S) Seismic Vessels towing heavy streamers and airguns, hence, high propulsion power demand 80

81 Underwater Noise Disturbing Marine Operations Disturbance of acoustical instrumentation Inaccuracies induced Masking = Non-function 81

82 External Noise in Ports Environment protection for residential areas

83 DNV GL Noise and Vibration Control Programme 83