B-Wageningen propeller diagrams

[zzerachiel]

Hy,

I searched all over the internet for the B-Wageningen propeller diagrams and couldn't find any good diagram.

I need the Kt-J, Kq-J with n0, kd and kn coeficients displayed.

Can someone tell me where i can find them ?

The only diagrams i've found have't got the n0, kd and kn coeficients and i really need them.

BTW, n0 is eta0

I need those diagrams for a didactical project.

Thank you.

[daiquiri]

Hello,
You can find it here:
http://deepblue.lib.umich.edu/handle/2027.42/3557

[zzerachiel]

I already have those, but i cannot find the above mentioned coeficients.

I was wondering if i can find the diagrams separated ( Kt-J and Kq-J ), since at college we work with that kind of diagrams.

[daiquiri]

Can you please define n0, kd ,and kn coefficients?

[zzerachiel]

Ok, here is how the diagram i work with is organized.

We have 2 diagrams KT-J and KQ-J, separated.

On each diagram we have :

P/D or H/D ( propeller pitch ) - family of horizontal curves ( ex. from 0.5 to 1.3 )
etaP = familily of vertical curves ( ex. from 0.1 to 0.75 )
etaOPT - another horizontal curve ( only one ), intersecting the etaP and P/D curves
DiameterOPT ( dOPT ) - a horizontal curve, just like etaOPT but beneath it

kd and kn are a series of curves intersecting all the above mentioned curves. Their profile is like a loose C.

The resulting diagram is similar to a rectangular triangle.

Those coeficients don't have a name, or at least i don't know it, they are part of the analitical formulas for the Kt and Kq

[daiquiri]

You have confused me with therms "horizontal curves" and "vertical curves". I've had to rotate the J-K diagram by 90° to grasp the meaning of your words.

I think you are looking for Bp-delta charts. You can get yourself a copy of Dave Gerr's "The Propeller Handbook". It costs around $10 + shipping fee at Amazon.com, but it is worth much more than that, you won't regret spending that money.

[zzerachiel]

As soon as i put my hands on the diagrams i will scan one of them and show it here

Thank you for your time.

[jehardiman]

Originally Posted by zzerachiel

Ok, here is how the diagram i work with is organized.

We have 2 diagrams KT-J and KQ-J, separated.

On each diagram we have :

P/D or H/D ( propeller pitch ) - family of horizontal curves ( ex. from 0.5 to 1.3 )
etaP = familily of vertical curves ( ex. from 0.1 to 0.75 )
etaOPT - another horizontal curve ( only one ), intersecting the etaP and P/D curves
DiameterOPT ( dOPT ) - a horizontal curve, just like etaOPT but beneath it

kd and kn are a series of curves intersecting all the above mentioned curves. Their profile is like a loose C.

The resulting diagram is similar to a rectangular triangle.

Those coeficients don't have a name, or at least i don't know it, they are part of the analitical formulas for the Kt and Kq

Is it really eta"P"? or is it eta"B" or eta"D" or eta"R"

eta"B" is the behind hull efficiency = measured thrust*Va/(2*pi*n*measured torque)

eta"D" is the propulsive efficiency = effective power/delivered power = eta"H"*eta"R"*eta"O"

eta"R" is the relative rotative efficiency = eta"B"/eta"O" = open water torque/ behind hull torque

eta"O" is the open water efficiency = open water thrust*Va/(2*pi*n*open water torque)

eta"H" is the hull efficiency = thrust deduction/wake fraction = (1-t)/(1-w) in Taylor notation

If the purpose of the graphic was to find the optimum D, n, and P/D given an value of eta"B", then it all make sense. Therefore, from the description kd and kn would be curves of constant diameter and constant rps.

Anyway, a picture of the graphic would help make more sense of what you are trying to find...kd and kn are not coefficients that I recall from van Manen. UofM bookstore through university Mircofilms used to have the original NSMB text and Bp-delta curves from the series. My copies are buried in a box right now.

[zzerachiel]

It is etaP as far as i can tell, the diagram i have is handwritten ( the letters/numbers not the lines ).

So, here is the path i must follow to make a preliminary design for the propeller :

Please excuse my bad english, but i'm romanian.

calculate AE/AD = (1.3+0.3z)T/(p0-pv)D^2+k
calculate Kn = 0.565Va/sqrt(n)*sqrt(sqrt(rho*Va/Pd);
find out Jopt from the KQ-J
calculate Dopt
etc

In the end i must have P/D, J, eta0 ( propeller randament ), KT.

I don't know if i named eta0 correctly

[b1ck0]

Kn - Optimal Diameter curve ( design parameter for D(opt) )
Kd - Optimal revolutions curve ( design parameter for n(opt) )

That's what he's looking for ... I have the diagrams of Bulgarian Ship Hydrodynamic Centre from 1983 and these curves are drown there but I don't have scaner now ....

The only thing I can do, is to interpolate the curves and give you the Equations ...

[zzerachiel]

Thank you b1ck0, that's what i'm looking for.

Sorry, but i'm rather new in the fied and i don't have much tehnical information.

I think that tomorow i will copy the diagrams tomorow and i hope this week i can scan them and upload them somewhere.

[b1ck0]

You will copy them, from where ?

[zzerachiel]

Well, i must give the project/homework until Thursday, and all i have to do from now is insert the coeficients.

The project/homework is pretty straight-forward but i can't do much without the diagrams.

No need to interpolate, but it would be nice to upload those diagrams somewhere

[zzerachiel]

Wel, from a friend, but i can get them tomorow.

They are from a book "Propeller Calculation" written by Horia DUmitrescu.

Again, sorry for the translation.

[b1ck0]

I will scan them ... but after 1-2 days ... if you want ... give me your propeller coefficients and I will tell you Kn and Kd