9 replies to this topic

[Tixa]

Hi, I've been trying to program my class pad 300 but it isn't working... If you have any program that solves Colebrooke-White formula (civil engeniering, hydraulic), please contact me! I really need it because I'm about to have exam

Thank you!

tixa986 AT yahoo.com.br

[girdeux]

Do you refer a program that you enter Reynolds number, Re; and relative rugosity, e; and it calculates the Fanning's factor, f? If you want it visit:
http://www.classpad....6ca3ba38647e661
It's based on Chen ecuation, it's runs in basic not in cplua, I did this program (it's a very easy program).

[Tixa]

I need to enter "caudal" (q) (I don't know how to say it in english...), diameter (D), equivalent rugosity (k) and "coeficiente de viscosidade din?mica" (v) (sorry, I don't know how to say it again...), and then the program solves the "Colebrooke-White" equation. I've got this program in BASIC, and I've translated it to Class Pad 300 language, but it always says that there is an error...
The program you're saying is another way to calculate the same thing, but this one is more rigorous. Thanks anyway! If you know anything about this program please contact me

[girdeux]

Ok is the same, with your variables you can calculete my variables, let's see:

Q: volume/time (caudal)
V: velocity
D: diameter
S: pipe section
ro: density
u: viscosity (kg/m/s)
uc: cinematic viscosity (m^2/s). uc=u/ro
e: absolute rugosity

Your variables are: Q,D,e,uc

e/D: relative rugosity (one of my variables)
Re=V?D?ro/u=V?D/uc, but first you need calculate V
If Q=V?S=V?Pi?D^2/4 -> V=Q?4/Pi/D^2 put the velocity in the up line and you will calculate the reynolds number, that is the another one of my varibles

Is the same, if you want, you can modify my program in order to input your variables. The Chen ecuation is enough accurate, if you prefer Colebrooke you will have to make it with cplua, I think that this ecuation needs a iterative method.

[Tixa]

ok, thank you! I'll try to do that! Yes, it needs an iterative method. Your program is in BASIC? can I run it on my class pad?or do I need do translate it to its language? and do I need to install anything in my pc to transfer it to class pad?

[girdeux]

The program can be run in the class pad, you don't have to change the lenguage, you only have to add your variables (if you don't know how to do that, tell me).

To pass the program from pc to class pad you need classpad manager, it's in the cd that comes with the classpad's box.

Are you mechanical engineer or chemical engineer?

[Tixa]

ok, thank you! I'll try to do that, if I can't do it I'll tell you. I'm still studying for beeing a civil engineer!

[girdeux]

I hope you speak Spanish.

In the "El Betoe's website":

http://ael.110mb.com/cptutorial.php

Point 2) click on the link "aqui"