PMID- 36928448
OWN - NLM
STAT- MEDLINE
DCOM- 20230321
LR  - 20230420
IS  - 1932-6203 (Electronic)
IS  - 1932-6203 (Linking)
VI  - 18
IP  - 3
DP  - 2023
TI  - Retrofit-induced changes in the radiated noise and monopole source levels of 
      container ships.
PG  - e0282677
LID - 10.1371/journal.pone.0282677 [doi]
LID - e0282677
AB  - The container shipping line Maersk undertook a Radical Retrofit to improve the 
      energy efficiency of twelve sister container ships. Noise reduction, identified 
      as a potential added benefit of the retrofitting effort, was investigated in this 
      study. A passive acoustic recording dataset from the Santa Barbara Channel off 
      Southern California was used to compile over 100 opportunistic vessel transits of 
      the twelve G-Class container ships, pre- and post-retrofit. Post-retrofit, the 
      G-Class vessels' capacity was increased from ~9,000 twenty-foot equivalent units 
      (TEUs) to ~11,000 TEUs, which required a draft increase of the vessel by 1.5 m on 
      average. The increased vessel draft resulted in higher radiated noise levels (<2 
      dB) in the mid- and high-frequency bands. Accounting for the Lloyd's mirror 
      (dipole source) effect, the monopole source levels of the post-retrofit ships 
      were found to be significantly lower (>5 dB) than the pre-retrofit ships in the 
      low-frequency band and the reduction was greatest at low speed. Although multiple 
      design changes occurred during retrofitting, the reduction in the low-frequency 
      band most likely results from a reduction in cavitation due to changes in 
      propeller and bow design.
CI  - Copyright: (c) 2023 ZoBell et al. This is an open access article distributed under 
      the terms of the Creative Commons Attribution License, which permits unrestricted 
      use, distribution, and reproduction in any medium, provided the original author 
      and source are credited.
FAU - ZoBell, Vanessa M
AU  - ZoBell VM
AUID- ORCID: 0000-0002-3494-4152
AD  - Scripps Institution of Oceanography, University of California San Diego, La 
      Jolla, California, United States of America.
FAU - Gassmann, Martin
AU  - Gassmann M
AD  - Scripps Institution of Oceanography, University of California San Diego, La 
      Jolla, California, United States of America.
FAU - Kindberg, Lee B
AU  - Kindberg LB
AD  - Maersk North America, Charlotte, North Carolina, United States of America.
FAU - Wiggins, Sean M
AU  - Wiggins SM
AD  - Scripps Institution of Oceanography, University of California San Diego, La 
      Jolla, California, United States of America.
FAU - Hildebrand, John A
AU  - Hildebrand JA
AD  - Scripps Institution of Oceanography, University of California San Diego, La 
      Jolla, California, United States of America.
FAU - Frasier, Kaitlin E
AU  - Frasier KE
AD  - Scripps Institution of Oceanography, University of California San Diego, La 
      Jolla, California, United States of America.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20230316
PL  - United States
TA  - PLoS One
JT  - PloS one
JID - 101285081
SB  - IM
MH  - *Ships
MH  - Sound Spectrography
MH  - *Noise
MH  - Acoustics
PMC - PMC10019734
COIS- The authors have declared that no competing interests exist.
EDAT- 2023/03/18 06:00
MHDA- 2023/03/22 06:00
PMCR- 2023/03/16
CRDT- 2023/03/17 09:10
PHST- 2022/07/29 00:00 [received]
PHST- 2023/02/20 00:00 [accepted]
PHST- 2023/03/17 09:10 [entrez]
PHST- 2023/03/18 06:00 [pubmed]
PHST- 2023/03/22 06:00 [medline]
PHST- 2023/03/16 00:00 [pmc-release]
AID - PONE-D-22-21393 [pii]
AID - 10.1371/journal.pone.0282677 [doi]
PST - epublish
SO  - PLoS One. 2023 Mar 16;18(3):e0282677. doi: 10.1371/journal.pone.0282677. 
      eCollection 2023.