Relation between skin friction and speed

Ease up a bit. Nothing is served by establishing a back and forth argument that is more personal than technical. One person questions your purpose. So what? It is his right to do so. No one is going to kick PAR off the forum as he is a regular contributor with often valuable information. Others are interested in the discussion. I am interested, but skeptical, based on past experience. My interest does wane when there are only promises not backed up by serious data.

I still have some of the material that that I retained that made these same claims 40 years ago. It is a synthetic long chain polymer that mimics the coating found on most fish. I did run some tests on an foil in the water with and without the coating. Although the coating made the foil so slippery that it could hardly be held in the hand, it had zero effect of the drag. Along with the results reported by USYRU, the US racing authority at the time who made similar tests, that is the reason for skepticism.

You must accept that such skepticism is normal and to be expected when a claim such as yours is made. However, should your product prove to be as claimed, there will still be other hurdles to clear. It is not likely to be approved for use on racing sailboats other than in specific cases although I don't know what these circumstances might be. Racing powerboats maybe, as their organizations are much more lenient on such things. Still, such a coating is bound to find useful application elsewhere if it is practical and economic.

 

Isn't human nature wonderful?

It really brings out the best in everyone doesn't it!

-Tom

 

Sorry hprasmus - if you look at PAR's posts you will see that he is well respected on this site and has helped many many many people - he doesn't in general mean anyone ill will. In fairness, I realize your actual question was not regarding the marketing of the product, but since you mentioned the product and linked to the graph on your facebook page and then can't discuss it, it left people feeling like you were marketing something that goes against common sense, and people tend to have a negative reaction when they are told about something that is "the next greatest thing" but "I can't give you the data on it."

Edit: thank you Tom for a better reply actually.

 

I tried similar coatings as a young man Tom and they didn't work, but did make a big mess. Hprasmus has yet to answer any reasonable questions, including the most obvious, such as why post here if you can't say anything. This is as telling a thing as I can imagine and smacks of something worthy of continued pursuit. If this chemical concoction could be incorporated into a coating that was say ablative in nature, then commercial vessels would jump all over it, assuming reasonable cost analyses and durability.

 

Hi Tom,

I really have no intention of continuing this chat because of the insults I have experienced here (from you know whom if you read the above). First time I tried this forum it seems to be a community of people that do not respond well to new ideas. And I have the feeling that that might be because I am from outside of the US of A.

To the kind persons that have contributed - Thanks - Henrik

 

No one said there were no sharks in the water .

 

Right Tom, but it is nice to know they prey!

 

I was very glad to see that you are back in these forums! Your contributions are usually well founded and useful for those with less experience.

But - I'm sorry to say - not this time! Henrik asked about any relationship between skin friction and speed. You are of course allowed to have your doubts about his product and its effectiveness (I have them, too!), but that has nothing to do with it!

And Henrik is certainly not obliged to answer any of your (or my or anyone else's) question regarding his product in order to get an answer to his own question! That is NOT how this forum works!

 

Hprasmus; I made a brief semi sarcastic comment above. There was no intention for personal affront.

Here is the deal..........Many of us, that frequent the forum, are old timers. Over the years we have been regaled with all sorts of wonderful claims for various products such as revolutionary boat designs or the incredible new engine concept or miraculous sails, etc, ad infinitum. Almost none of those wonders of science and inventiveness have been shown to be effective or useful. Forgive us for being skeptical and saying so. In addition there are a few of us who have developed a personality trait that might be called "in your face rebuttal" That is also not to be construed as a personal attack.

Your skin friction reduction scheme is a worthy mental exercise but it does go against the general principals of fluid mechanics.

Incidentally TSpeer is our resident hydro and aerodynamic guru. He is a very respected authority in this area of study. If Tom is skeptical of an idea, we are too.

Peace.

 

Hey, lets announce a product, back it up with absurd claims, substantiate this with innuendo from some unknown, previously unheard of A/C formula, further reinforce this with "pro in tank testing", which of course can't be published and ask that everyone just accept and find a "happy place" with it. Now lets target the smallest market we can and hope for the best?

Maybe it's just me, but this sure does sound like a used car salesman working a "pitch". You're are correct Soren, Henrik isn't obligated to answer questions, but why would anyone post something like this and not expect questions, if not out right challenges?

If I posted on a round world discussion forum, insisting the world was flat, wouldn't I have to expect some sword play? Why not now? What is different about Henrik's discussion/product offering, that instantly elevates him above the need for investigative questioning, particularly in regard to the seemly difficult to accept statements (50% reduction . . .)?

As I mentioned previously, if there was a product offering in the works, that did just half of what he suggests, the lawyers would be battling for production rights as we type. Millions of dollars would have been transferred into private accounts by now. The testing would be absorbed by those that can afford these types of ventures and some sort of lump sum or royalty fee arrangement already worked out, marketing plans stratified and graphics shops putting the final touches on packaging, banners and ad campaign slogans.

Maybe it's a translation issue, maybe cultural, but this thread has felt slimy from the first. At first I got the impression it was a student trying to be clever about his exam, but then the product announcement suggested something else, then no solid information, no testing data, hell not even a chemical base to work with. If you're going to drop hints, at least drop a something tangible.

It's not a personal affront Henrik, though I do seriously question your marketing savvy, let alone what the press is going to do when this gets to them. If you think I'm tough, well you'll need to grow some skin thickness pretty quickly.

Lets try this again Henrik. Is it a polyurethane? What is the general viscosity at 80 degrees F? Man made or organic? Can it be tinted or does it have a color? Odor? Sure there's lots you can't tell us, but I'm sure there's lots that you can tell us, like does it work on a molecular level or a larger scale? Does it require rougher surfaces to keep it in place or will a smooth surface some how become smoother? I'm certain there are physical properties about this goo that could be published without harm to potential patent or product protection.

 

From what snake is it extracted?

 

I can not meet my promise of pulling out of this forum without a last goodbye. So, PAR spend your time on things you know about. And don't discredit me or my products. You are pathetic.

Henrik

 

Found by whom?

Has this research been independently verified and subjected to international peer review?

If the answer is yes, great, please show us (I sit on several international committees, not heard of this one yet!)

If the answer is no, then the "results" must be verified and be subjected to scrutinty. If you, or they, do not like having to answer questions of their 'claim' then that all it is, a claim. And anyone can make a claim, but to support said claim, is another matter.

Engineering has no place for emotions, just facts. If you have become emotive over this issue, then i suggest you choose another product to market, as this is upsetting you personally. Engineers only like facts and proof, not claims.

 

:idea: Can it be applied to concrete submarines?

 

Please NOOOOOOOOOOOOOOOOOOOOOOOOOOO