"Calculating Korifice Value in Cranes TP 410M, Problem 7-12

  • Thread starter Thread starter gmaverick2k
  • Start date Start date
  • Tags Tags
    Value
Click For Summary

Homework Help Overview

The discussion revolves around calculating the Korifice value in the context of Cranes Technical Paper 410M, specifically problem 7-12. Participants are attempting to derive this value using given parameters such as the discharge coefficient (Cd) and the beta ratio.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants are calculating the Korifice value using different methods and parameters, questioning the accuracy of their results compared to those presented in the technical paper. They discuss the relationship between the coefficients and the beta value, and some express confusion regarding the equations used.

Discussion Status

The discussion is active, with multiple participants sharing their calculations and results. Some have noted discrepancies between their findings and those in the technical paper, suggesting a potential error in the original problem setup or expression. There is no explicit consensus yet, but various interpretations and approaches are being explored.

Contextual Notes

Participants reference different editions of the technical paper, which may contain variations in the equations presented. There is mention of using specific Reynolds number values and the potential for typographical errors in the problem statement.

gmaverick2k
Messages
42
Reaction score
3
Homework Statement
Calculate Korifice by substituting Cd and beta values
Relevant Equations
See image
1682613442985.png

This is taken from Cranes Technical paper 410M problem 7-12. I cant seem to get the Korifice value by substituing the Cd and beta value. For example for beta = 0.7 & C = 0.7, I'm calculating Cd = 0.61 and Korifice = 28.0 (not 4.34 as shown) using excel. Is this an error?
 
Physics news on Phys.org
1682616305504.png

Page A-21. Using Re = 8e5 for relating C and beta
 
gmaverick2k said:
I'm calculating Cd = 0.61 and Korifice = 28.0
So am I . There must be something wrong in the ##K## expression: the numerators are ##\approx 0.93## denominators ##\approx 0.12##

##\ ##
 
My old copy (1986, imperial units) shows
$$K_{orifice} \cong \frac{1-\beta^2} {C^2 \beta^4}$$

EDIT: and this is Example 4-12 in the old book, not 7-12 (possible typo in OP?)
 
  • Like
Likes   Reactions: gmaverick2k
gmax137 said:
My old copy (1986, imperial units) shows
$$K_{orifice} \cong \frac{1-\beta^2} {C^2 \beta^4}$$
ISO 5167-2:2003, (pdf version pops up first link in google)
pg. 14.. same eq. as in Crane for Korifice...

1682620396003.png
 
gmax137 said:
My old copy (1986, imperial units) shows
$$K_{orifice} \cong \frac{1-\beta^2} {C^2 \beta^4}$$

EDIT: and this is Example 4-12 in the old book, not 7-12 (possible typo in OP?)
not a typo, example 7-12:
1682620652265.png
 

Attachments

  • 1682620638854.png
    1682620638854.png
    12.5 KB · Views: 141
  • Like
Likes   Reactions: WWGD
I got the same result as you in Excel (most current version). I also plugged the equation into WolframAlpha and got the same result (both results for Korifice).
 

Similar threads

  • · Replies 42 ·
2
Replies
42
Views
4K
  • · Replies 29 ·
Replies
29
Views
4K
  • · Replies 13 ·
Replies
13
Views
4K
  • · Replies 1 ·
Replies
1
Views
4K
Replies
4
Views
3K
Replies
2
Views
7K
Replies
7
Views
3K
  • · Replies 62 ·
3
Replies
62
Views
11K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
4
Views
24K