Sherlock Holmes, that incredible detective, would be impressed with the new technologies and lateral thinking being employed to detect the ever more silent submarines (or subs) lurking below the surface of our oceans. Sonar (or acoustics) has been used in the past but is rapidly being ineffective.


Dear Colleagues

EIT Stock ImageSherlock Holmes, that incredible detective, would be impressed with the new technologies and lateral thinking being employed to detect the ever more silent submarines (or subs) lurking below the surface of our oceans. Sonar (or acoustics) has been used in the past but is rapidly being ineffective.

The thinking and approach to finding new technologies is quite inspirational and is not confined only to subs but  could surely be used in a huge variety of other fields (e.g detecting sharks/rescuing people etc).

Debye Effect
Other approaches have been used to employ disturbances in the Earth’s magnetic field caused by the metal hull (referred to as MAD or magnetic anomaly detectors) but these require the detector to be relatively close to the sub.

A particularly novel approach in tracking subs is referred to as the Debye Effect and this relies on a magnetic signature of the sub’s wake. Sodium Chloride (NaCl) is the key component of sea water and physical movement (from a passing vessel) tends to shake the Na and Cl ions around with a resultant weak magnetic field created (called the Debye effect). The Russian, Chinese and American governments are racing against each other in coming up with a solution to apply this effect to a workable technology.

Technology Used to Beat Detection
On the other side of the fence, needless to say, the various navies around the world are spending a lot of money on new technologies to hide their very expensive submarines. One is use of fluid cloaking which alters the flow of water over the submarine to make them appear invisible. Acoustic cloaking on the other hand uses materials to refract sound waves (from a sonar) around the submarine and thus to hide it more effectively.

We can go far further than Subs – think of the incredible opportunities

I do realize that this is all specifically about detecting submarines but these technologies can be applied to a myriad of other uses. For example, detecting sharks near beaches or helping with rescuing people or tracking whales and general fish stock are all ideas that come quickly to mind.

Perhaps, a clever solution to hiding (subs, for example) is as per Robert Ferrigno’s (Sins of the Assassin) suggestion: Best place to hide was in a crowd.

Yours in engineering learning

Steve

Mackay’s Musings – 8th Nov’16 #625
780, 293 readers – www.idc-online.com/blogs/stevemackay