The ability to be undetected in naval industry, or stealth, is vital for maritime defence companies when developing a vessel design and subsequently building and testing a ship.
The critical stealth of submarines can be compromised easily with noise, making it crucial to understand any problems early in the design stage, rather than when at sea. New equipment such as fans, pumps, superchargers and motors must be vetted by a team of technicians and engineers. The vibration and acoustic signatures of this machinery is measured and analysed according to in-house standards and matched up to stringent acceptance limits, that ensure the repeatability of measurements and thus reliable accept/reject criteria.
For this purpose French naval shipbuilder DCNS has selected a Danish multinational engineering company Brüel & Kjær and its PULSE system.
The PULSE measurement and analysis platform – and PULSE Data Manager – have cut significantly the speed and ease with which DCNS can perform tests – and share and compare data across the entire organisation.
According to Measurement Technician Anaud Mesnill, “Measurements that took five to six hours can now be completed in less than two hours.”
DCNS has customised and streamlined many of the measurement tasks, and now has many gigabytes of data stored on central servers from five years of tests, including those dating back five years. Aside to having a comprehensive database, the ability to tailor interfaces to the specific requirements of individual tasks is now essential for efficient operation.
DCNS uses PULSE for acceptance testing of electro-mechanical equipment and for vibro/acoustic control of on-board systems. Sound and vibration assessment covers sound intensity, vibration, underwater acoustics, modal analysis, sound power and mobility. These measurements are performed throughout the organisation, which totals over 13,000 employees worldwide and at many different sites including Brest, Lorient, Nantes-Indret, Toulon and Cherbourg.
Different operations use PULSE for vastly different applications such as acceptance testing, design, R&D, maintenance and troubleshooting. Measurements for sound intensity, underwater acoustics, radiated noise, vibration analysis, machine diagnostics and modal analysis are collected, processed, analysed, stored and managed by the PULSE platform.
Naval Today Staff, January 14, 2014; Image: DCNS