A few points, and then I'll leave this topic and go back to cursing my dremel for not being able to cut through thick GRP hull layups.
first, it should be always remembered that what we're talking about is a hobby. So really none of this matters at all. When I'm not building boats, or planes, I play with toy soliders. It's just for fun. So I'll say again that I hope I'm not causing any one any annoyance.
Second, I'll say that I always shudder when people say "lets leave things how they are, because if there was something better, some one else would have though of it".
Is everything to do with boat design for racing SO GOOD that it is only miniscule changes that are left to work on? If so, that means that there will soon be an optimal formula that will never be bettered.
To me, looking in from the outside, it seems unlikely. While not an expert in any way, I know enough about hydro and aero dynamics to at least make the statement "There are other alternatives that are worthy of exploration". The concept I discussed about may, as I said, be completely and utterly wrong. But there are LOTS of completely different paradigms that seem to remain completely un-explored in the model racing world that are either being discussed or actively used in the full sized world. examples are dynamic ballasting, asyemtric hulls ( which there is a lot of work on at the moment in float tanks ), beaver tails, aero properties etc etc etc.
let me give one, small and trivial, example: In the standard configuration of a mid mounted engine exposed to the open air, or under a canopy, that is used in most ORMA boats, there is going to be a lamiear shear that acts on the surface of the top deck at speed. End result? The faster the boat goes, the less air is available to it, as most of it will be buffeted away by the hull. Obviously there is air present, but their could be more.
Could aero properties, or even just a simple cone linked to the inlet of the engine, be used in such a way as to provide a positive pressure on the inlet to the engine? Absolutely! It's a principle used in every racing car. And it would take very little work, depending on the design chosen, to add this to the boats. It DOES happen in the full sized boats.
By making this one adjustment, will a slow boat turn in to a winner? Nope. But it will be acting more effeciently. So what happens if you add dynamic ballsting AND air ramming AND a different hull design AND aero work AND enhanced surface properties to a single boat? Will you will then? it's not definate, as a lot of it is in driver skill, and reliability, and lots of other factors, but it certainly won't hurt....
There doesn't seem to be any ruling against it. So why isn't it done? I expect there are a lot of reasons, but I'll hedge my bets, and say that one of the main reasons that would be given, conciously or sub-conciously is "That's the way we've always done it". And thats where traps lie.
A second example: I go fishing a lot. Often for carp. carp fishing is the most expensive type of fishing in UK fresh waters. The amount of gadgets, kit, equipment etc etc that the magazines suggest is enormous. Ultimately, carp fishers only use three rigs, but there are at least 1,000 different published variations, tiny variations on those three. Use Hook X rather than type Y. Use a square weight rather than a round one etc. Most of the entire sport is utterly locked onto making tiny changes to those three rigs.
Turns out that often, by using a float, or by fly fishing, rather than a weight, you often catch more fish. But very few carp fishermen do. Why? becuase there's no float in any of the three basic rigs. And they've had the concept of those three basic rigs hammered in to them, sub-conciously, for years. SO they MUST be right. Right? Nope, it's just that everyone has convinced everyone else that three, often sub-optimal designs, are the only way of fishing.
Is there a lesson here? maybe. I could, however, be talking utter rubbish. And I wouldn't know, like I said, I'm not an expert. But I do read the design forums for the full sized boats, and the stuff on there which is considered "fast" or "cutting edge", bares no relation to the Deep V, Tuned Pipe and Struuder set up that the model boats use.
Lastly, one bladed props:
Pro's: they are better. On boats a lot better than on planes.
Con's: They are a swine to set up and have to be re-set up on a regular basis.
Why aren't they used? I don't know. I *do* know they are a more optimal design. My Pa said they were, and a few guys at my old boat club also discussed them. becuase I'm a cynical so and so, I never believe anyone about anything without lots of proof, so I went away and researched it. And my research made me comfortable with the concept. But I assure you that when I first started to think about it, it seemed completely and utterly stupid.
In my personal opinion, and in lots of peoples opinion who studied this sort of thing at school, they are a useful tool to the "how to make a boat go fast" arsenal. But I could be wrong. So could the clever blokes. A hell of a lot of clever boat builders argued against building ships out of steel. A lot of material scientists thought that the idea of glass fibre was silly. A lot of clever economists though communism was a good plan.
Anyway, once again thanks for the inputs on the concepts I was thinking about.
Steve
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Topic: Quick question about OMRA boat design (Read 10970 times)