IEEE Consultants' Network of Long Island

Loop Current Antics - Dick LaRosa

I have found that the intrusion of the Loop Current (LC) into the Gulf of Mexico (GoM) depends on the difference in monthly average mean sea level (MSL) between Grand Cayman Island in the Caribbean and Settlement Point in the Bahamas. A deep intrusion of the LC into the GoM results in a big pool of warm, deep water which can energize hurricanes (like Katrina) that threaten the Gulf Coast. I estimate that there is about 60 GW more hydraulic drive power pushing water through the GoM, Florida Straits and Florida Current Channel when the LC intrusion is large, compared to when there is no intrusion. If we use floating turbines in the Yucatan Channel, Florida Straits, and Florida Current to generate electric power for desalination when we have the extra drive, we can keep the LC from intruding and reduce the hurricane threat to the Gulf Coast. We can store the fresh water for use when the sea level drive is absent.

About 35,450 dual-turbine units are required to convert the excess sea level drive into electric power for desalination. We need good data to justify such a project, but the tide gage stations on Grand Cayman have not been operational since 1996. Rather than attempt to get these rebuilt and functioning, I have been learning  more about the Gulf of Mexico NearReal-Time Altimeter Data Viewer. There are two products available on a daily basis: the Sea Surface Height (SSH) Anomaly, and the SSH Anomaly with the Model Mean added. The SSH Anomaly is the daily SSH altimeter data with a long-term average subtracted out. The Model Mean is the long-term average with the Geoid subtracted out. The Geoid is the sea surface without the LC. So when you add the Model Mean to the SSH Anomaly, you get the daily altimeter data with the Geoid subtracted out. This is the second product available on the website, and it is actually the default product when you first sign onto the website. It bears a good resemblance to the LC, but I'm learning that it's not as perfect as I used to think.

I used to think that the LC followed the 17 cm contour on this plot. However, the Aug 27, 2010 SSH shows a big slow-down with a big bulge in the separation between the 0 to 30 cm contours. At this point in the LC path, the 40 and 50 cm contours are closest together, indicating that this is the location of the highest velocity, which is the nominal center of the LC. This is evidence that the LC shifts to a higher contour if it slows down. This makes sense because the greater potential energy of the high-altitude contour replaces the kinetic energy lost in the slow-down. There is a 30cm peak in the SSH Anomaly at this point, so the LC is really passing over a hill that is making it slow down. My simple picture of gravity flow should still be valid in the Florida Straits and Florida Current, but the LC requires a lot more work.

MERCEDES-AMG-SLS-E-CELL --Carl Schwab

 Somewhat "tongue-in-cheek" about a year ago I wrote a blog about 4WD and 4WS, which referred to an Ecar with 4-wheel drive and 4-wheel steering. My main reasoning was this was a way to make the Ecar fun to drive, safe AND less costly.

Well guess what? Mercedes is leaking info about an Ecar planned for introduction in 2013. It's in prototype/refinement now. Although is does NOT have 4-wheel steering it DOES have 4-wheel drive using 4 motors allowing sophisticated vector powering control for superior traction control during maneuvering. BTW Mercedes has a gasoline version of this car without 4-wheel drive and both it and the Ecar (E-CELL) accelerate to 60pmh in 3.9 seconds

What I am impressed with is the packages they use for the front and rear axle of the E-CELL. Both have two motor packages that are combined much as a differential housing mounted to the frame and stub axles to the CV joint or wheel. It would be and it is obvious that for 4-wheel steering, (if they think of it) is using two of the front axle units for both axles. The rest is computer software/firmwareNow the insane part about this project is strategy of starting at $185,000 for the ECELL.

CONCLUSION
Both the GM VOLT and now the Mercedes E-CELL have some wonderful technology for controlling Ecars. BOTH are suffering birthing pains but I do think that the 4WD-4WS Ecar will evolve and become the suburban vehicle of choice in the 21st century, but at a 10 to 1 price reduction!

Coriolis Again - Dick LaRosa

When slow-moving Caribbean Sea water speeds up to pass through the narrow Yucatan Channel, it enters the Gulf of Mexico (GoM) at a greater height than the Caribbean sea surface. It has gained both KE and PE. The source of this added energy is the KE stored in the Earth's rotation. The Coriolis force diverts the warm, light-weight, fast water at the top of the Yucatan Current to the right, making a hill of warm water. The Yucatan Current flows along the sloping side of this hill. The stream water moves forward in accordance with the law of inertia, but this interferes with the GoM water that is at rest with respect to the rotating Earth. The interference tends to slow down the Earth's rotation, so the gain in KE and PE of the stream is at the expense of the KE stored in the Earth's rotation. The Coriolis force acts like a valve that controls the flow of energy from the Earth rotation KE reservoir to the Yucatan and Loop Current system. This concept is going to be a tough sell to the oceanographic community. Many oceanographers think that the Coriolis effect is just a mathematical transformation between inertial and rotating coordinate systems, but I think it has great importance in determining how much power we need to extract with turbines to eliminate the Loop Current from the GoM.