![]() We made a good start she’s still the benchmark in quiet underwater sound today. “If I look back, it started in 2001 with the Irish research vessel Celtic Explorer. Tjakko Keizer, principal research engineer at Damen, has been working on underwater sound levels on Damen vessels for almost a decade. To these ends, Damen R&D has developed a continual ship design feedback loop based on four stages: predict levels, adjust design accordingly, measure levels, update model. Adding underwater sound measurement to our scope gives us control of a wider part of the shipbuilding process. Besides, it makes sense to measure underwater noise on our own vessels, in the same way we look at characteristics such as speed or bollard pull, for example. ![]() It also gives confidence to some clients keen to maintain confidentiality about their vessels’ performance – for example, navies. Many shipyards outsource the profiling of underwater sound to classification societies or specialist companies, but Damen has always chosen not to follow this path.ĭoing it in-house is cost-effective for our clients. To begin with, this had little to with ecology, but with ensuring the quiet operation of, for example, naval ships and research vessels." "We have been conducting research into the underwater sound profile of our ships for many years. That, for example, fish larvae may be killed by the sounds of pile driving as offshore construction takes place, that certain creatures may suffer not only hearing damage, but also undergo behavioural changes as a result – even very straightforward changes like loss of sleep.ĭamen is well positioned to assist with the development of quieter ships – it’s something the shipbuilder has been working on for many years already, as Damen’s Manager R&D valorisation Edwin van Buren explains: There are indications that the impact of underwater noise may go further down the food chain too. Interruptions in sound can literally compromise marine mammals’ survival. These creatures have evolved using sound to communicate with each other and to locate their pray. Perhaps the most obvious impact is that on marine mammals. The effects this has on marine life are poorly understood, though it’s clear that there are effects. It’s certainly not the loudest, but it is the most widespread and, as vessels ply their trade across oceans and seas, day and night, throughout the seasons, the sounds of shipping are unceasing. There are numerous factors – military activity, offshore energy exploration and operations and, of course, shipping. In fact, it’s been estimated that underwater sound has doubled every ten years for the past six decades. Leaving aside for now complexities relating to different frequencies and hearing ranges and keeping things simple, it’s easy to imagine that underwater sound today is both more prevalent and loud. What is perhaps surprising about this is that, when Leonardo da Vinci said it, it was 1490 and ships did not yet have engines. The statement itself does not come as a surprise – the connected nature of water molecules relative to, say, air molecules, simply put, ensures sound can travel a lot further underwater. If you cause your ship to stop and place the head of a long tube in the water and place the outside extremity to your ear, you will hear ships at a great distance from you.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |