Recent content by Dnomyar

This is getting tedious. There is no LIFT equation in the Scale velocity calculation. They are not connected. They do not affect each other, nor are they relalted at all. They are as different as can be !

Scale Model Formulae Further to the Scale Spped Calculation discussion, I found further clarification at http://www.charlesriverrc.org/articles/design/ibtherkelsen_scalespeed.htm What scalemodelers should know In order not to bore readers more than necessary, the outcome is presented...

I have no idea what you are talking about, sorry. The formula I use is a straight conversion of model velocity to an equivalent full size Velocity. As far as I know, its no more involved than scaling the Weights down to 1:5 scale ModelWeight = FullSizeWeight /(5*5*5) or scaling the...

Yes, this is the popular tank testing. Measuring the drag is with a spring balance, or a Load Cell with the water current providing the flow requires an expensive tank setup. Putting the measuring device on the boat means I can run it in any flat water pond or dam. Also, measuring the 'Weight'...

I find Rhino a great way to "knock up" structure like this. At the end, you can get precise angles and dimensions if you want to build from it. I can even animate things with the Bongo addon or

The Froude Number is calculated by Speed to be scaled to Fn FL=v/((g*LWL)^0,5) FL= Froude Number by length v= speed in m/s LWL= Length on waterline g= free fall acceleration 9,812m/s2 It has nothing to do with the Scale Formulae that i can see That would be true if...

yes indeed, but how would one do that ? yes, i am understanding that. Yes, hence the actual testing. All the mathematical models will not cover every factor. I can't follow that. The 'weight' I am detecting is the Force while the motor is Pushing against the hull. If the propeller...

http://en.wikipedia.org/wiki/Trajectory_of_a_projectile for various formulae, but I couldn't see the one you were using. You are right, you need to specify the velocity - it may be part of the trick, in the question. I would simply supply the angle and velocity to reach the target (...

Sorry, it was a transposition error from my spreadsheet. Thanks for the checking. Weight in Grams 800 Equivalent in Kilos 0.8 Equivalent in Newtons 0.7848 Kilometres Per HOUR 6 = Metres Per Second 1.666666667 =Newton Metre Per Second 1.308 = Joule Per Second 1.308...

Ya got to check this out for spur gears

Try this one - its better :-)

Thanks Jack - you have indeed struck the crux of the question. The relationship between the Pressure ( Pascals ) and Force (Newtons), as you can tell from the title of the thread, was what I thought I would need to establish for measurements. By taking the Pressure at the motor/boat...

Yes indeed. The theoretical drag x velocity would give a good approximation of engine power required. I have subjected the model to a number of calculations that give me much more accurate predictions ( see attached) , but the difference between theory and practice can be considerable. For...

or save yourself the read - the solution is " If you can't ask a question which is anymore specific than "how do I build a particle accelerator" you probably need to do at minimum a few solid months of research on your own to get to the point where you have a chance. Then come back and maybe...

This might help