Recent content by ajd-brown

Hi, yes thanks for your input however I have solved the problem and it correlates with experimental results from previous tests. I will post this later on this evening to complete the thread. I ended up using an polytropic process of Pv^(cv/cp) = C And by calculating this for both the large...

It is the same. The lower graph has been created by Fox (a company that sell shocks) and I am trying to achieve the same graph in excel using an ideal gas approximation. Yes, there is. You are spot on! I hadn't thought of that until now! Essentially there is a secondary smaller volume under...

Thank you for your reply, I am trying to create the second graph using data I have for a bicycle shock absorber. Shock travel is essentially the compression of the `air spring'. So at 0 travel, the force is zero because the spring is at its free length (although this is technically not true...

I am trying to calculate the spring rate for an air filled shock-absorber, however I am struggling to get my head around the change non-linearity at the start of compression. Obviously if the shock is fully extended then it will be applying no compressive force to the chassis so that accounts...

that makes so much more sense! as you say I included the h^2 accidentally so that must be where i went wrong, I'll try and solve it the original way again and see if I get the same answer! From what I can see a needs to be 2 and b has to be -1

I have found a as 1 is that correct? and using that value I get b as b=((((hdf(x)/dx + 3/2*h^2*d2f(x)/dx))))/f(x)

Ok that's great thank you! I am going to attempt it now that I understand it! I'll place my answer on here afterwards, I gather you have found them then?

Hi, I don't really understand the notation you have used there with the lines, but does that basically mean that the equation holds true when differentiated once and in its original form? so just to check my understanding, if it was supposed to be 3rd order accurate, there would be a third...

Hi could anyone give me pointer as to where to go with part iii please?

Thats great thanks for your help, I now understand the last few steps of generating the coefficients which I was missing before! I did notice a few mistakes as you said. Are these last fews steps anything to do with the Riemann sum or is that something else entirely?

I have done a test on a 4 piston test engine which is expected to exhibit torsional resonance at 800RPM and a vertical translational resonance at 1200RPM. The data we gathered from the test bed machine was as follows: Theta | Signal 0 | -5 60 | -1 120 | 7 180...

if the battery transfers 50 coulombs of energy to a capacitor and it takes 100 seconds to do so because the current supplied from the battery is low, say 0.5A, the charge = 100 x 0.5 A = 50 Coulombs, then if this charge is released in 10 seconds instead, the current flow will be 5A... and the...

well that's a relief, but why does it not give more power? i thought the capacitors could release much higher currents than batteries, so if the voltage has increased, and the current is higher, surely power will increase :(

Also, I know the resistors are ridiculously small, I just wanted to charge the capacitor quickly...

Hi, I am trying to double DC voltage from 3v to 6v apparently this circuit works... charge in parallel discharge in series, can somebody shoot me down and tell it won't work please? Thanks Anthony