289:, the engines and alternators let out unwanted noise and vibrations. To solve this, the solution is a double elastic suspension where the engine and alternator are mounted with vibration dampers on a common frame. Then, this is mounted elastically between the common frame and the hull. While in megayatchs the requirement is the comfort of crew and passengers, in other applications, such as navy ships, the requirements involve that the engines or generators should work under certain shock loads. To achieve this the ships install double elastic suspensions and high deflection mounts are installed between the unit and base frame. Beforehand, the engineers calculate the
93:, on the other hand, when new and/or in good repair, do not, by themselves generate excessive vibration as long as the turbine blades are in a perfect condition and rotate in a smooth gas flow. But after some time microscopic defects appear and cause small pits to appear in the surface of the intake and the blades which set up eddies in the gas flow, resulting in loss of performance and vibrations. Vibration levels may change with different loading conditions or when doing a manoeuvre.
251:
makes the necessary choices concerning the ship's structure to achieve an optimized design towards noise and vibration control. Decisions are made about the engine and shaft, what kind of instruments and material can be used to reduce noise and vibrations throughout the vessel and what is the best
49:
driven vessels, the engines induce large accelerations that travel from the foundation of the engine throughout the ship. In most compartments, this type of vibration normally manifests itself as audible noise. The problem with diesels is that, for a given size, there is a fixed amount of power
260:
of the different parts/sections and adaptions can be done to the structure. On board, noise travels through the structure (mainly low frequencies), more than through the air, so insulating the engine room is not enough as a way to avoid the noise travelling through the boat.
387:
J. Le
Besnerais, V. Lanfranchi, M. Hecquet and P. Brochet, "Optimal Slot Numbers for Magnetic Noise Reduction in Variable-Speed Induction Motors," in IEEE Transactions on Magnetics, vol. 45, no. 8, pp. 3131-3136, Aug. 2009. doi:
101:
Besides mechanical produced vibrations, other sources are caused by the motion of the sea, slamming of the vessel on the waves and water depth to mention just a few. The main problem here is that they are less controllable.
27:
are not the same but they have the same origin and come in many forms. The methods to handle the related problems are similar, to a certain level, where most shipboard noise problems are reduced by controlling vibration.
281:
at the origin, skewing the electric motor or choosing a better slot/pole combination will reduce electromagnetic force harmonics or avoid resonances between magnetic forces and structural modes of the electric motor.
305:
of the joints, tightening of the bolts, good alignment of stern contour of the vessel, adjusting of variables following the weekly and monthly schedule are the most effective routes to noise and vibration control.
36:
The main producers of mechanically created noise and vibration are the engines, but there are also other sources, like the air conditioning, shaft-line, cargo handling and control equipment and mooring machinery.
230:
Noise generated on board ships and submarines can have far-reaching effects on the ability of the vessel to operate safely and efficiently. Military vessels in particular need to be quiet to avoid detection by
277:
mounting of engines, elastic holding of pipes or dampers can be installed. These will absorb a part of the vibrations (and the noise) produced by the machines. To control the
256:
technology tries to simulate these vibrations under different ship conditions to provide an overview of weak spots. The generated vibrations are also compared with the
278:
75:
119:
70:
Large vessels sometimes use electrical propulsion motors, the electrical power being provided by a diesel generator. Noise and vibration of
235:, so many methods have been used to limit a vessel's noise signature. Controlling noise is therefore a defense measure, most acutely for
58:
all on its own. This results in an increase of vibrations spread all over the ships structure. Crankshaft vibration can be reduced by a
910:
726:
398:
1063:
128:
920:
802:
716:
1057:
905:
756:
434:
1104:
315:
Lloyd's
Register Technical Papers; Ship vibration and noise: some topical aspects by J.S. Carlton and D. Vlašić
109:
between the engine and the gearbox. These type of couplings are used because of their low torsional stiffness.
50:
generated per cylinder. To increase power it is necessary to add cylinders but, when cylinders are added, the
590:
966:
873:
1099:
721:
443:
105:
The engine-gearbox interaction is usually a source for noise and vibrations. Here, it can be installed
54:
has to be lengthened and after a very limited number of additions, the lengthened crankshaft begins to
363:
1068:
1016:
646:
539:
131:(gago) sets some standards for vessels. The table below gives some comparisons of preferred maximum
930:
519:
301:
Regular maintenance will have a major influence on the performance of instruments and machines.
853:
788:
751:
117:
Exposure to noise and vibrations is regulated and limits for maritime vessels are given in the
338:
1042:
887:
731:
293:
or the 6/12 degree of freedom to guarantee the optimum combination of couplings and mounts.
951:
468:
8:
711:
706:
524:
427:
412:
290:
270:
257:
132:
122:
standard 6954: Guidelines for permissible mechanical vibrations on board seagoing vessels
78:
due to electromagnetic forces which is responsible for the "whining noise" of the motor.
55:
767:
657:
981:
976:
772:
596:
493:
478:
458:
225:
59:
1074:
1047:
1021:
601:
534:
498:
1052:
1006:
971:
961:
839:
529:
488:
248:
681:
626:
606:
420:
274:
71:
1093:
1037:
1011:
746:
621:
574:
569:
564:
554:
549:
473:
86:
46:
736:
686:
616:
127:
Because there are different noise regulations from country to country, the
762:
741:
676:
668:
611:
544:
483:
302:
90:
339:"Diesel & Gas Turbine Worldwide Spring 2020 | Powered by Pocketmags"
663:
652:
636:
631:
463:
286:
236:
51:
956:
24:
253:
106:
641:
364:"Vulkan: il segreto per creare il silenzio a bordo degli yacht"
863:
824:
817:
514:
232:
20:
442:
74:
include, besides mechanical and aerodynamic sources, an
318:
269:
To control the mechanical vibrations at the origin,
1091:
219:
428:
435:
421:
135:on board of vessels and onshore levels.
911:Signal-to-interference-plus-noise ratio
1092:
727:Equivalent pulse code modulation noise
416:
65:
850:(energy per symbol to noise density)
264:
319:International Maritime Organization
129:International Maritime Organization
13:
921:Signal-to-quantization-noise ratio
336:
112:
14:
1116:
835:(energy per bit to noise density)
803:Carrier-to-receiver noise density
717:Effective input noise temperature
252:way to implement these. Advanced
40:
446:(physics and telecommunications)
124:to protect personnel and crew.
96:
1058:Block-matching and 3D filtering
906:Signal-to-noise ratio (imaging)
757:Noise, vibration, and harshness
391:
381:
356:
330:
296:
1:
591:Additive white Gaussian noise
309:
242:
16:Problem in naval architecture
967:Interference (communication)
874:Signal-to-interference ratio
864:Signal, noise and distortion
400:Solutions for generator sets
343:digimag.dieselgasturbine.com
7:
722:Equivalent noise resistance
220:Noise and vibration control
137:
81:
10:
1121:
279:electromagnetic vibrations
223:
31:
1030:
1017:Total variation denoising
999:
990:
944:
781:
697:
583:
507:
451:
388:10.1109/TMAG.2009.2020736
247:At the design table, the
107:highly flexible couplings
931:Contrast-to-noise ratio
406:. 2020. pp. 19–20.
854:Modulation error ratio
789:Carrier-to-noise ratio
752:Noise spectral density
144:Noise limit land (dB)
76:electromagnetic source
1105:Mechanical vibrations
1069:Denoising autoencoder
1043:Anisotropic diffusion
888:Signal-to-noise ratio
732:Impulse noise (audio)
647:Johnson–Nyquist noise
535:Government regulation
147:IMO noise limit (dB)
19:On maritime vessels,
952:List of noise topics
291:torsional vibrations
712:Circuit noise level
707:Channel noise level
368:Barche Magazine ISP
258:natural frequencies
1100:Naval architecture
768:Pseudorandom noise
658:Quantization error
469:Noise cancellation
66:Electrical engines
1087:
1086:
1083:
1082:
1022:Wavelet denoising
982:Thermal radiation
977:Spectrum analyzer
773:Statistical noise
597:Atmospheric noise
494:Noise temperature
479:Noise measurement
459:Acoustic quieting
265:Control at source
226:Acoustic quieting
217:
216:
60:harmonic balancer
1112:
1075:Deep Image Prior
1064:Shrinkage Fields
1048:Bilateral filter
997:
996:
602:Background noise
499:Phase distortion
437:
430:
423:
414:
413:
408:
407:
405:
395:
389:
385:
379:
378:
376:
375:
360:
354:
353:
351:
350:
334:
138:
56:flex and vibrate
45:When looking at
1120:
1119:
1115:
1114:
1113:
1111:
1110:
1109:
1090:
1089:
1088:
1079:
1053:Non-local means
1026:
1007:Low-pass filter
992:
986:
972:Noise generator
962:Colors of noise
940:
847:
843:
832:
828:
777:
699:
693:
673:Coherent noise
649:(thermal noise)
579:
503:
489:Noise reduction
447:
441:
411:
403:
397:
396:
392:
386:
382:
373:
371:
362:
361:
357:
348:
346:
337:Seiler, Robin.
335:
331:
312:
299:
267:
249:naval architect
245:
228:
222:
115:
113:Exposure limits
99:
84:
72:electric motors
68:
43:
34:
17:
12:
11:
5:
1118:
1108:
1107:
1102:
1085:
1084:
1081:
1080:
1078:
1077:
1072:
1066:
1061:
1055:
1050:
1045:
1040:
1034:
1032:
1028:
1027:
1025:
1024:
1019:
1014:
1009:
1003:
1001:
994:
988:
987:
985:
984:
979:
974:
969:
964:
959:
954:
948:
946:
945:Related topics
942:
941:
939:
938:
928:
918:
908:
903:
885:
871:
861:
851:
845:
841:
836:
830:
826:
821:
814:
800:
785:
783:
779:
778:
776:
775:
770:
765:
760:
754:
749:
744:
739:
734:
729:
724:
719:
714:
709:
703:
701:
695:
694:
692:
691:
690:
689:
684:
682:Gradient noise
679:
671:
666:
661:
655:
650:
644:
639:
634:
629:
627:Gaussian noise
624:
619:
614:
609:
607:Brownian noise
604:
599:
594:
587:
585:
584:Class of noise
581:
580:
578:
577:
572:
570:Transportation
567:
562:
557:
552:
547:
542:
537:
532:
527:
522:
517:
511:
509:
505:
504:
502:
501:
496:
491:
486:
481:
476:
471:
466:
461:
455:
453:
449:
448:
440:
439:
432:
425:
417:
410:
409:
390:
380:
355:
328:
327:
326:
322:
321:
316:
311:
308:
298:
295:
266:
263:
244:
241:
224:Main article:
221:
218:
215:
214:
211:
208:
207:sleeping area
204:
203:
200:
197:
193:
192:
189:
186:
182:
181:
178:
175:
174:control rooms
171:
170:
167:
164:
160:
159:
156:
153:
149:
148:
145:
142:
114:
111:
98:
95:
87:Steam turbines
83:
80:
67:
64:
42:
41:Diesel engines
39:
33:
30:
15:
9:
6:
4:
3:
2:
1117:
1106:
1103:
1101:
1098:
1097:
1095:
1076:
1073:
1070:
1067:
1065:
1062:
1059:
1056:
1054:
1051:
1049:
1046:
1044:
1041:
1039:
1038:Gaussian blur
1036:
1035:
1033:
1029:
1023:
1020:
1018:
1015:
1013:
1012:Median filter
1010:
1008:
1005:
1004:
1002:
998:
995:
989:
983:
980:
978:
975:
973:
970:
968:
965:
963:
960:
958:
955:
953:
950:
949:
947:
943:
936:
932:
929:
926:
922:
919:
916:
912:
909:
907:
904:
901:
897:
893:
889:
886:
883:
879:
875:
872:
869:
865:
862:
859:
855:
852:
849:
848:
837:
834:
833:
822:
820:
819:
815:
812:
808:
804:
801:
798:
794:
790:
787:
786:
784:
780:
774:
771:
769:
766:
764:
761:
758:
755:
753:
750:
748:
747:Noise shaping
745:
743:
740:
738:
735:
733:
730:
728:
725:
723:
720:
718:
715:
713:
710:
708:
705:
704:
702:
696:
688:
685:
683:
680:
678:
675:
674:
672:
670:
667:
665:
662:
660:(or q. noise)
659:
656:
654:
651:
648:
645:
643:
640:
638:
635:
633:
630:
628:
625:
623:
622:Flicker noise
620:
618:
615:
613:
610:
608:
605:
603:
600:
598:
595:
592:
589:
588:
586:
582:
576:
573:
571:
568:
566:
565:Sound masking
563:
561:
558:
556:
553:
551:
548:
546:
543:
541:
538:
536:
533:
531:
528:
526:
523:
521:
518:
516:
513:
512:
510:
506:
500:
497:
495:
492:
490:
487:
485:
482:
480:
477:
475:
474:Noise control
472:
470:
467:
465:
462:
460:
457:
456:
454:
450:
445:
438:
433:
431:
426:
424:
419:
418:
415:
402:
401:
394:
384:
369:
365:
359:
344:
340:
333:
329:
324:
323:
320:
317:
314:
313:
307:
304:
294:
292:
288:
283:
280:
276:
272:
262:
259:
255:
250:
240:
238:
234:
227:
212:
209:
206:
205:
201:
198:
196:dining rooms
195:
194:
190:
187:
184:
183:
179:
176:
173:
172:
168:
165:
162:
161:
157:
154:
151:
150:
146:
143:
140:
139:
136:
134:
130:
125:
123:
121:
110:
108:
103:
97:Other sources
94:
92:
88:
79:
77:
73:
63:
61:
57:
53:
48:
38:
29:
26:
22:
934:
924:
914:
899:
895:
891:
881:
877:
867:
857:
838:
823:
816:
810:
806:
796:
792:
737:Noise figure
698:Engineering
687:Worley noise
617:Cosmic noise
559:
540:Human health
399:
393:
383:
372:. Retrieved
370:. 2018-01-13
367:
358:
347:. Retrieved
345:. p. 40
342:
332:
300:
284:
268:
246:
229:
133:noise levels
126:
118:
116:
104:
100:
91:gas turbines
85:
69:
44:
35:
18:
763:Phase noise
742:Noise floor
677:Value noise
669:White noise
612:Burst noise
530:Environment
525:Electronics
508:Noise in...
484:Noise power
303:Lubrication
297:Maintenance
1094:Categories
1031:2D (Image)
664:Shot noise
653:Pink noise
637:Infrasound
632:Grey noise
464:Distortion
374:2021-06-06
349:2021-05-30
310:References
287:megayachts
273:fittings,
243:Prevention
237:submarines
52:crankshaft
957:Acoustics
520:Buildings
271:isolating
152:workshop
25:vibration
991:Denoise
325:Specific
254:computer
185:offices
163:kitchen
82:Turbines
1000:General
993:methods
898:,
452:General
275:elastic
32:Sources
1060:(BM3D)
782:Ratios
642:Jitter
593:(AWGN)
545:Images
47:diesel
1071:(DAE)
868:SINAD
818:dBrnC
759:(NVH)
700:terms
575:Video
560:Ships
555:Rooms
550:Radio
515:Audio
444:Noise
404:(PDF)
233:sonar
141:Area
21:noise
925:SQNR
915:SINR
89:and
23:and
935:CNR
900:SNR
858:MER
285:In
213:60
210:45
202:65
199:55
191:65
188:55
180:75
177:55
169:75
166:60
158:85
155:70
120:ISO
1096::
844:/N
829:/N
811:kT
366:.
341:.
239:.
62:.
937:)
933:(
927:)
923:(
917:)
913:(
902:)
896:N
894:/
892:S
890:(
884:)
882:I
880:/
878:S
876:(
870:)
866:(
860:)
856:(
846:0
842:s
840:E
831:0
827:b
825:E
813:)
809:/
807:C
805:(
799:)
797:N
795:/
793:C
791:(
436:e
429:t
422:v
377:.
352:.
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