Computers can calculate the possibility of the wind and wave hit to drilling platforms then helps engineers to design a more solid platform which can resist wind and tide hit. It also can provide a digital experiment for new ship type which helps engineers improve the performance of ships.

"Numerical Tank”, a virtual test environment using computers to build a experiment tank without sidewalls for ships and marine buildings, is an subject for DUAN Wenyang and his team. DUAN Wenyang is the chief scientist of Collaborative Innovation Center of Offshore and Ship Technology (CICOST), the Yangtze River Scholar and the Distinguished Professor of HEU. His subject that “Top-layer Research on the Virtual Test Environment” has got support from the Ministry of Industry and Information Technology.

Common tanks have many shortages such as big investment, long constriction period, defective functions, irreversibility and unsatisfied to the rapid growth of ship and sea engineering. Take a deep sea platform as an example. If it is a semi- submersible drilling platform with 5000㎡ surface projection above water, the square of its underwater mooring system will be equal to the scope of Beijing within the Fifth Ring Road. Compared to common tanks, numerical tanks with the assistant of computers and hydromechanics software is more efficient. It has shorted time period, lower cost and it is easier to have remote control at the same accuracy. So numerical tanks can decrease the uncertainty of design and increase the possibility of design optimization.

Numerical tank has its own basic theory. First researchers will use computer to simulate liquid flow and finding the answer of the hydrodynamical motion equation. Then they will use computers with the help of software to simulate objects motions and other things which cannot be simulated in common tanks. Finally, they can give us a better design plan of ship types or deep sea platforms with the data colleted from the numerical tank. This research is a main technology support to the transformation from common tank test environment to virtual test environment. It is a new tendency of international hydrodynamics. It is a revolutionary development of the ship and sea engineering design methods. It will has important theory and engineering significance.

DUAN Wenyang said, take the spar platform test as an example, if we make a test to the spiral damping plate which is the core of the spar platform in a common tank , we will spend at least half month and millions of money. But if we use numerical tank, we only cost 12 hours in computer working and 1152 yuan.