Daily Archives: January 23, 2013

This Tiny Shark Can Take Out Nuclear Submarines

Cookiecutter shark (Isistius brasiliensis)

NOAA/Public Domain

The Cookiecutter shark (Isistius brasiliensis).

The cat-sized shark in the picture to the right doesn’t look that intimidating, but it has the power to take down an entire nuclear submarine. The fish’s strange bite can get at the softer areas of the submarines, National Geographic’s Ed Yong reports: 

The fearless cookie-cutters have even disabled the most dangerous ocean creature of all—the nuclear submarine. They attacked exposed soft areas including electrical cables and rubber sonar domes. In several cases, the attacks effectively blinded the subs, forcing them back to base for repairs. They later returned, fitted with fibreglass coverings.

The attacks happened in the 1970s and the problem seems to have been taken care of, though in several cases the sharks did enough damage to the vessel’s sonar equpiment that the oils inside that transmit sound would leak out of the ship and break the equipment — the subs could no longer see what was around them, according to the Reef Quest Centre for Shark Research.

Nuclear subs obviously aren’t all that tasty, but they seem to bite just about anything — even research equipment in the ocean. The distinctive bites have been found in all kinds of fish and other sharks, and even a human has been attacked by the little guys.

Source – Business Insider

 

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Australia – Defence tenders for a $2 million supercomputer

High performance computer cluster will be used for computational fluid dynamics modelling to assist in submarine designs

The Department of Defence plans to deploy a high-performance computer (HPC) cluster to execute computational fluid dynamics simulations that support its Future Submarine program, in a project set to begin in March this year.

Defence Science & Technology organisation (DSTO) issued a tender for the rollout of a supercomputer with associated software and services, which is expected to cost between $2 million and $2.4 million.

“The DSTO high performance supercomputer will support and conduct of science and technologies studies for the Future Submarine program,” a Defence spokesperson told CIO.

“These studies will assist with the development of requirements and provide technical advice to government aimed at reducing risk in critical areas for the project,” the spokesperson said.“
The computer system will enable numerically-intensive computational fluid dynamics (CFD) modelling required to assist in the understanding of the manoeuvring and signature performance of existing and potential submarine designs.”

The supercomputer will also be used to solve equations representing the time-dependent fluid flow around a submarine, its propeller and associated appendages, the Defence spokesperson said.

“The CFD simulations will involve discretising the volume of fluid about the submarine geometries to create meshes. The fluid equations are solved for each discrete point or cell in the mesh and the new system will be used to solve mesh sizes ranging [from] five million cells to greater than 100 million cells,” the spokesperson said.

The system will process the largest 100 million cell CFD simulations in days rather than months using existing DSTO computing facilities, Defence said.

The DSTO said it would deploy OpenFOAM-based solvers and, to a lesser extent, ANSYS Fluent/CFX software packages on the supercomputer “that are capable of efficiently solving problems in parallel across several thousand CPU cores.”

The HPC cluster will be integrated with DSTO’s existing hardware, which is networked using a quad data rate (QDR) Infiniband switch, and provides connectivity speeds of up to 40Gbps.

A network-attached storage node, running the Red Hat Enterprise 6 operating system, will provide storage for the HPC cluster; while a high-end HP Z800 workstation, running Centos 6, will act as a login node the cluster, the department said.

In September 2012, the government announced that it was establishing a Future Submarine Systems Centre in Adelaide, the home of the Future Submarine program. The government wants to acquire 12 new submarines, which will be assembled in South Australia.

Source – CIO