Software combines loading simulation with emergency response capability

Having achieved an average 20% annual growth rate over the last 10 years, Helsinki-based Napa, an independent software house that develops systems for naval architecture, is expanding its range of services. The company has two software programs applicable to the offshore sector - NAPA for engineering design and Onboard-NAPA, which handles loading, performance and damage stability calculations.

Having achieved an average 20% annual growth rate over the last 10 years, Helsinki-based Napa, an independent software house that develops systems for naval architecture, is expanding its range of services. The company has two software programs applicable to the offshore sector - NAPA for engineering design and Onboard-NAPA, which handles loading, performance and damage stability calculations.

With software interchangeable between both end products, Napa is seeing the greatest growth in its Onboard-NAPA system. "There is a clear interest in Onboard-NAPA in the floating production market as well as for tankers, LPG carriers, and cruise ships," says sales and marketing manager Carl Johan Schauman.

The company has made many improvements to the Onboard-NAPA package since it was first introduced in 1992. One of the main developments is a loading sequence. If flow rates are known, Onboard-NAPA can make time domain loading simulations and can show the stability and strength of a ship as a function of time either graphically or in tabular format. All calculations are based directly on a real 3D model of the vessel, which gives better accuracy in various draught, trim, and list conditions compared with systems using hydrostatic tables.

Onboard-NAPA has a function that will warn if specified parameters are about to be exceeded with the alarm time set according to customer's needs. Another development is a more extensive way of calculating the outflow of cargo. Should an oil spill occur following a collision, the program defines the point of impact and therefore the theoretical extent of the spill by taking into account environmental data such as sea conditions.

"Onboard-NAPA is not just about loading sequences, as there are lots of packages on the market that can do this," continues Schauman. "The advantage of our system is that it combines loading data with an emergency response tool, which is why it has been selected by many of the world's major classification authorities such as DNV." During 1998, Napa also sold systems to Lloyd's Register of Shipping and the Ship Stability Research Centre at the University of Strathclyde, amongst others.

While the company has experienced a 100% growth rate for its sales of Onboard-NAPA, its original naval architectural package, NAPA, is still seeing a good growth rate with about 15 new customers buying the system last year. NAPA, too, is subject to constant development in addition to minor maintenance upgrades, with the most recent development being an improved graphics user interface. For both NAPA and Onboard-NAPA, customers can purchase regular upgrades rather than having to buy a whole new package.

Structure modeling

A sub-system of the NAPA package launched last year - NAPA Steel - is now being sold commercially to existing customers. The system defines the structural properties of areas such as deck and shell plating and provides a modeling method that is fast enough to satisfy early design stages - where frequent changes are made - while still handling sufficient information up to the level required for structural approval.

"We are selling NAPA Steel to existing customers as there is still some development work to be done." says Schauman.

Copyright 1999 Oil & Gas Journal. All Rights Reserved.

More in Rigs/Vessels