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Physical Models In an Age of Computers
Harperdog points out this article "about the Bay Model in Sausalito, California, which was built in 1959 to study a (terrible) plan to dam up San Francisco Bay. The model was at the forefront of research and testing on water issues that affected all of California; its research contributions have been rendered obsolete by computer testing, but there are many who think it could contribute still. Now used for education and tourism, the model is over 1 1/2 acres and replicates a 24-hour tidal cycle in just 14 minutes. Good stuff."
There was also the Army Corps of Engineers model of the entire Mississippi/Missouri/Ohio/Arkansas/Red river basins. It was built by POW labor near Clinton, MS. See what's left of it here. http://maps.google.com/maps?ll=32.30606,-90.316173&spn=0.003922,0.006335&sll=36.977452,-121.987122&sspn=0.118622,0.202732
Computer models may be far more efficient for research but physical models still have a very important role. Children, while far more efficient then ever at using technology, do not have the ability/opportunity to learn from these computer models like a researcher would. I think physical models are still very important for teaching the next generation about different science and engineering principles, like the tide cycle from the article. The ability for kids to physically see and experience the science and engineering topics is what gets them interested and engaged in learning about those topics in the future. Models like this are essential for future education for kids. I mean what kid doesn’t start to wonder about the world around them after going to the local science center?
I imagine testing of scale (including full scale) models is still used in most industries. Computers help you reduce the number of mistakes and shorten the iterative development cycle so you make fewer elementary errors.
In Oil & Gas, almost all of the major manufacturers have been modeling all their new components in 3D for the last decade. You can have whole departments dedicated to running Finite Element Analysis on these 3D models. It's not as simple as putting in your constraints (loads, fixed and pinned reaction points, etc) and hitting "solve". You still have to make certain assumptions, tailor the matrix (the 3D lattice/approximation made of pins and beams) or make simplifications to the model if you want it to converge toward a solution. The computer solves the cases iteratively. Once you think you're close, you perform a test at scale and verify your assumptions. Then your match it to your computer model and hopefully you're not too far off. For example, things like incorrect friction factors between materials matter a lot when they are amplified by huge forces. The manufacturer of a particular coating may claim it's .07 (if they even tell you). You learn it's more like 0.08 through repeated testing. At this point there is no way of calculating things like that.
Of course, this assumes that you have the time, money, and server time to run such experiments. Most of the time you focus on the one or two critical areas of a design for FEA and use past experience or classic formulas on the rest. Customers still want final tests before product ships, so technically you have one last point to catch a failure/issue before it ships.
For what it's worth, this is the same Bay Model the Mythbusters used in their season 1 episode Alcatraz Escape.
The accurate reconstruction of the tidal effects allowed them to convincingly show that a raft would be unable to reach Angel Island, and that a more plausible route would have been toward the Marin Headlands - before confirming the model's result experimentally.