IEEE Consultants' Network of Long Island

Evaporator Raft Construction Details - Dick LaRosa

I think I have figured out how to attach individual solar absorber plates to stringer cables (or ropes) so that large rafts can be assembled, rolled up, and deployed from workboats. The individual absorber plates are hardwood 6 inches wide and 18 inches long, with the grain parallel to the long dimension. The thickness is tentatively 0.25 inches. A thickness of 0.375 inches would be stronger, but the additional buoyancy might make it more difficult to weigh the plate down so that it floats just below the water surface. Cross pieces perhaps one inch square and 6 inches long would be fastened across the absorber plate at each end and would protrude through the water surface to stabilize the floating depth. If some force pulls the absorber plate down, the additional displacement will provide an upward force to maintain the absorber at the correct depth. The idea is for the absorber plate, painted black, to heat the thin layer of water above the plate to facilitate evaporation. The cross pieces will also be painted black so they will attain a high surface temperature and evaporate water that splashes on them.

The absorber plate and cross piece are sandwiched between a top and bottom plate made of a metal that, together with its surface treatment, will survive in sea water. Exactly what is unknown to me at this time. But it will have to be compatible with two hefty flat-headed rivets that hold a pair of wires against the bottom plate. The wires have round loops bent in their respective ends that fit around the rivets. The rivets pass through predrilled holes in the metal and wood parts of the sandwich, and the top end of each rivet is upset by a rotating forming tool that squeezes the wires, metal plates, and wood pieces together. The metal plates have bent edges with notches to position the wires. The wires are bent upward at a right angle far enough from the absorber plate to allow free passage of a stringer rope. The wire spacing at the left end of the absorber is different from the spacing at the right end, so that one pair of wires fits between the wires of the neighbor. A whole row of plates, making up the entire width of the raft, is laid down and the stringer ropes are dropped between the nested, upward pointing wires.

There are two right-angle wire bending operations performed by multiple tools simultaneously on all the wires. The first operation bends the top ends of all the wires toward their respective absorber plates. The second operation bends all wires so that they fall into the notches of their respective top plates with the first bend hooked over the wood cross piece to resist forces tending to pull the absorbers away from each other. I originally thought there would be six rows of absorber plates strung on seven stringers, giving a raft width of nine feet plus the spaces to captivate the stringer ropes. Tooling is required for bending 24 interleaved wires in opposite directions with the ability to retract the tools and get ready for the next set of absorbers. I have visions of short pins with beveled flanges so that the wires don't slip off. Also we need a series of floating clamps to hold the plates in position during the second bending operation. The clamps and bending tools must float because there are cumulative tolerances in the six-plate width.

Considering all the problems and unknowns, I don't have any urge to go to more than six rows of absorbers with a total width slightly more than nine feet. I need to learn about metals in sea water, metal working, tooling, fixturing, and whatever. I don't even know the language to describe what is needed. But I'm a lot better off than when I didn't have the foggiest notion of how to assemble a complete raft.

Cloud Seeding - Dick LaRosa

 In 1962, Doubleday published a book by Louis J. Battan titled "Cloud Physics and Cloud Seeding". In 2003, Dover republished it unabridged, but changed the title to "Cloud Physics: a popular introduction to applied meteorology". I bought the Dover edition about ten years ago, and was surprised to find that the title, which had attracted me, did not accurately describe the contents. The book languished on a shelf, until I recently went searching for anything I had that might help explain weather. It is still not a balanced introduction to meteorology, but it definitely is relevant to rainmaking. In fact, most people think that cloud seeding is the only way to make rain. There was some excitement a few years ago about electrical means for rain making, but I haven’t seen much about that lately. 

Modeling Rainmaking - Dick LaRosa

The following is a letter sent to the editor of the Bulletin of the American Meteorological Society (BAMS) in the hope of stirring up interest in modeling the precipitation enhancement scheme described in the letter. AGU refers to the American Geophysical Union:

Rainfall Enhancement in the Central United States

I am studying the design and application of solar-heated evaporator rafts moored in coastal waters for enhancing the moisture content of air flowing inland across the Louisiana-Texas (LA-TX) Gulf coast. During the summer, wind from the Bermuda High picks up moisture from the sea and supplies it to the central plains states. The natural evaporation process is inefficient because sunlight penetrates to considerable depth, so that the solar energy is absorbed by a large depth of water with consequently small surface temperature rise. A black solar absorber surface floating just below the water-air interface would heat only a small volume of water, with greater temperature rise and consequently increased evaporation rate. I have experimented with wood boards about 0.25 inch thick, 4.5 inch wide, and 16.25 inch long. The latter dimension would allow three rows of boards to be strung on cables or ropes on 17-inch centers, which would allow a small raft section to be rolled up and transported on the rear seat of my sedan. This would allow the demonstration raft to be transported to a swimming pool to observe its behavior in waves created by energetic young people. The ballast provided by cables and attachment fittings would be sufficient to sink the 0.25-inch boards. A stable depth can be achieved by attaching 1.25-inch-wide by 4.5-inch-long wood cross pieces on top of the 0.25-inch boards at both ends of each board. The height of these cross pieces would be sufficient to insure that the raft will not sink, even when loaded by accidental debris. These cross pieces would also serve as attachment points for the fittings that are used to string the absorber plates on the cables or ropes.

Coriolis Effect or Coriolis Force? - Dick LaRosa

 For a projectile going through thin air over some spot on the Earth, there is essentially no Coriolis force. The projectile passes over a particular spot on the Earth at t=0. A coordinate system, whose origin is at that particular spot, is locked to the Earth surface with its x-y plane tangent to the surface. This coordinate system rotates about its z-axis through an angle

t omega sin(latitude)

in a small time interval  t. Omega is the angular rotation rate of the Earth about its polar axis. The projectile is moving at velocity  v, so its lateral displacement from the point where it would have been in a non-rotating coordinate system is

Borers - John Dunn, Consultant, Ambertec, P.E., P.C.

I came across this tree one day while taking a little walk in the neighborhood. This tree is in trouble!!

Wind Power Complications - Dick LaRosa

Wind turbines are supposed to provide electric power without adding CO2 to the atmosphere. This would be accomplished if our electric power requirements varied with time to match the availability of wind power. But a wind farm in any given location will face periods of low or no wind. There are also times when the wind velocity is too high and the wind turbine's blades must be feathered and braked to prevent damage. It might be hoped that the distribution of wind farms throughout a geographic area might be such that power can be dispatched from a wind farm that is producing power to a load area that is temporarily without wind power. A monumental scheduling problem would result from attempting to supply one area exclusively with wind power produced in various places scattered over a wide geographic area. The total sum of available wind power might be more constant than the power available from one farm, but there will be some unmatched surpluses. Moreover, the present transmission infrastructure is not adequate to tie all these areas together, so we must look for ways to fill in locally when wind power is not adequate.

Drought in the USA - Dick LaRosa

This year we have had severe drought over much of the US and it is appropriate to consider the application of solar-heated evaporator rafts to enhance rainfall. The design that seems to work is a dark absorber plate suspended just below the water surface. Solar radiation is absorbed by the dark surface and heats the thin layer of water above the absorber plate. The water surface reaches a higher temperature compared to the temperature for an unmodified water surface where the solar radiation penetrates to many meters depth and heats a much larger volume of water. The enhanced temperature increases the rate of evaporation, resulting in greater humidity of the air passing over the raft. Depending on where this moistened air goes and what processes it undergoes, we might get to see increased precipitation where we need it. So where might we put evaporator rafts ?

DRILLERS REUSING ‘FRACK WATER’----Carl Schwab

Energy firms are exploring recycling options for an industry that consumes up to 5 million gallons per well. That IS a lot of water. Companies are racing to find ways to recycle the water used in hydraulic fracking, chasing an emerging market perhaps worth billions of dollars. From energy industry giants Halliburton Corp. and Schlumberger Ltd.  to smaller outfits such as Ecologix Environmental Systems LLC these companies are pursuing technologies to reuse the “frack water” that comes out of the wells after hydraulic fracturing or “fracking”---the process of using high pressure water and chemicals to coax oil and natural gas out of shale-rock formations.

While the recycled water is not cleaned sufficiently for drinking purposes, it can be cleaned of chemicals and rock debris and reused to frack additional wells, which could sharply cut the costs that energy companies face securing and disposing of the used water. Schlumberger predicts that a million new wells will be fracked around the world between now and 2035 and further predict that reducing freshwater usage will no longer be just an environmental issue.

Sea Surface Height Data Viewers - Dick LaRosa

http://jeffreyearly.com/science/qg-eddies-paper/

http://eddy.colorado.edu/ccar/data_viewer/index

The first link above leads to Jeffrey Early's animated global display of westward propagating clockwise and counterclockwise eddies. One can clearly see both CW (red spots) and CCW (blue spots) eddies forming where the Amazon River discharge meets the North Brazil Current. These red and blue spots pass through the Caribbean Sea toward the Yucatan Channel, where the blue spots seem to pass smoothly into the Gulf of Mexico, while the red spots seem to hesitate, and then pop into the Gulf. But there appear to be fewer red spots entering the Gulf than are arriving at the Yucatan Channel. This leads me to think that the CW eddies are trapped in the Loop Current's loop, and lose their individual identity. Then new rings break off from the Loop Current and drift westward in the Gulf of Mexico.

Violent Ultraviolet - Dick LaRosa

My 2009 Hyundai Sonata was equipped with a set of expensive name brand tires. Three and a half years and 10,000 miles later all four sidewalls were badly cracked and the right front sidewall was peeling off in big chunks. It had been in the right rear for the first part of its life and was then switched to the front. I have been feeling out curbs for more than 60 years, but I don't think I'm abusive. The sidewalls have always outlasted the treads, but this time I had to kiss a set of hardly-worn treads goodbye.