When you have questions about the safety and operability of your vessel’s design under heavy seas, Vard Marine’s ship motion analysis serves up the answers.
Using advanced seakeeping codes, we calculate the motions your ship will experience and deliver accurate seakeeping predictions. This allows us to assess the effectiveness of potential design changes, and leads to the precise selection of motions reduction equipment and design features.
These techniques can be applied equally to a paper design or to solving a known motions problem with your present vessel.
Vard Marine’s added value
The stand-out feature of our ship motion analysis service is our team’s exceptional ability to augment the codes we use with an additional layer of mathematical analysis. The result is innovative solutions suited to each client’s unique challenge.
Challenges like a crane’s load swing, or gangway motions at oblique angles are tough tasks where Vard Marine’s engineers excel.
THE CLIENT ADVANTAGE
When carried out during the design phase, ship motion analysis gives you a prognosis for the operability of your ship and allows us to design-in optimal mission effectiveness and high levels of crew safety and comfort.
Our calculations can also be used to create guidelines for the safe and effective operation of the ship.
HOW WE WORK
In particular, we use ship motion analysis to assess the vessel’s response in several functional areas, and determine whether it will be fit for your purpose.
TO ASSESS OVERALL OPERABILITY, WE ANALYSE:
- vessel motions / accelerations / loads
- rates of slamming / propeller emergence/ deck wetness
- speed loss due to waves
WE CAN ALSO PREDICT PERFORMANCE OF MISSION TASKS, SUCH AS:
- helicopter take off/landing
- boat launch and recovery
AND OF COURSE, WE’RE ABLE TO PREDICT THE EFFECTS OF MOTIONS ON CREW PERFORMANCE:
- motion sickness rates
- motion interruption index
For seakeeping calculations, we typically use the ShipmoPC code developed by Defense Research & Development Canada (DRDC). A strip-theory code created for displacement monohulls, ShipmoPC is well validated by numerous model tests and sea trials.
However, depending on your vessel type and mission, we may select other codes which include:
- PRECAL – a 3D panel code for ships with an unusual hull design
- PRETTI – an extension of PRECAL to non-linear time domain simulations
- AQWA– a 3D panel code for offshore structures
We don’t stop there
We instrument vessels to quantify six degree-of-freedom motions either via trials or medium-term monitoring. This helps to quantify real-world performance, exactly identify and rectify issues with your existing ship, and develop operational guidance.
Read our parent vessel design scaling case study for the Irish Naval Service where ship motions analysis was conducted.