But what use might this device be? Random 'walks' through the ocean, which seems to be what it is used for, but beyond that?
With only one knot of speed, no matter how it was guided, the thing if caught in the Gulf Stream in Florida it would end up off the coast of Portugal before its batteries required attention. That is, if it didn't go aground before then, which with a routine depth profile of 4,000 feet it surely would, to stay forever there on the ocean bed. Lawry -----Original Message----- From: Michel Jullian [mailto:[EMAIL PROTECTED] Sent: Tuesday, February 12, 2008 1:18 PM To: vortex-l@eskimo.com Subject: [Vo]:Re: Ocean glider uses ocean heat differentials Good point. Having air inside must be indispensable anyway to offset the weight of the metal hull and batteries. Michel ----- Original Message ----- From: "Robin van Spaandonk" <[EMAIL PROTECTED]> To: <vortex-l@eskimo.com> Sent: Tuesday, February 12, 2008 3:07 AM Subject: Re: [Vo]:Ambient temperature variations powered engine? (was Re: Ocean glider uses ocean heat differentials) In reply to Michel Jullian's message of Tue, 12 Feb 2008 01:26:20 +0100: Hi, [snip] >Thanks Lawrence this makes more sense, the initial BBC article and the WHOI press release stated, wrongly it now seems, that "[the surface] heat is used to push oil _from a bladder inside the hull to one outside_". If it's the other way round as the WP article below suggests (oil from outside to inside at the surface), then the outside oil bladder needs not contain anything but oil as I am sure Robin will agree. [snip] While I do agree strictly, consider that the oil is incompressible, and hence always takes up the same volume (almost) whether inside or outside. If the oil can be pumped into the device, then that means that there must be something compressible inside the device, i.e. an air bladder. In short, it makes no difference where that bladder is, as long as it is part of the device. The reference I provided to the manufacturers web site, makes clear that there is at least one air bladder. Regards, Robin van Spaandonk The shrub is a plant.
