Difference between revisions of "Gray correlation"

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(Workflow Hg)
(Workflow Hg)
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:<math> \rho_m = \rho_L C_L + \rho_g (1-C_L) </math>
 
:<math> \rho_m = \rho_L C_L + \rho_g (1-C_L) </math>
  
:<math> \sigma_L = \frac{\sigma_o + 0.617 \sigma_w WOR}{1 + 0.617 WOR}</math>
+
:<math> \sigma_L = \frac{\sigma_o + 0.617\ \sigma_w\ WOR}{1 + 0.617\ WOR}</math>
  
 
:<math> N_V = 453.592\ \frac{{\rho_m}^2 {v_m}^4}{g_c \sigma_L (\rho_L - \rho_g)} </math><ref name= Gray/>
 
:<math> N_V = 453.592\ \frac{{\rho_m}^2 {v_m}^4}{g_c \sigma_L (\rho_L - \rho_g)} </math><ref name= Gray/>

Revision as of 19:09, 4 April 2017

Brief

life is good with Gray[1]

Math & Physics

Following the law of conservation of energy the basic steady state flow equation is:

 144 \frac{\Delta p}{\Delta h} =  \bar \rho_m + \rho_m \frac{f v_m^2 }{2 g_c D} + \rho_m \frac{\Delta{(\frac{v_m^2}{2g_c}})}{\Delta h}[1]

where

 \bar \rho_m = \rho_L (1-H_g) + \rho_g H_g, slip mixture density
 \rho_m = \rho_L C_L + \rho_g (1-C_L) , no-slip mixture density

Colebrook–White [2] equation for the Darcy's friction factor:

 \frac{1}{\sqrt{f}}= -2 \log \left( \frac { \varepsilon'} {3.7 D} + \frac {2.51} {\mathrm{Re} \sqrt{f}} \right)[3]

The pseudo wall roughness [1]:

 \varepsilon' = \begin{cases} 
\frac{28.5}{453.592} \frac{\sigma_L}{\rho_m v_m^2},  &\mbox{if } R \geqslant 0.007 \\
\varepsilon + R \frac{\varepsilon'-\varepsilon}{0.0007}, & \mbox{if } R < 0.007 
\end{cases} , with the limit  \varepsilon' \geqslant 2.77 \times 10^{-5}

Reynolds two phase number:

 Re = 2.2 \times 10^{-2} \frac {q_L M}{D \mu_L^{C_L} \mu_g^{(1-C_L)}}

Discussion

Workflow Hg

 M =SG_o\ 350.52\ \frac{1}{1+WOR}+SG_w\ 350.52\ \frac{WOR}{1+WOR}+SG_g\ 0.0764\ GLR[4]
 \rho_L= \frac{62.4\ SG_o + \frac{Rs\ 0.0764\ SG_g}{5.614}}{B_o} \frac{1}{1+WOR} + 62.4\ SG_w\ \frac{WOR}{1 + WOR}[5]
 \rho_g = \frac{28.967\ SG_g\ p}{z\ 10.732\ T_R} [5]
 \rho_m = \rho_L C_L + \rho_g (1-C_L)
 \sigma_L = \frac{\sigma_o + 0.617\ \sigma_w\ WOR}{1 + 0.617\ WOR}
 N_V = 453.592\ \frac{{\rho_m}^2 {v_m}^4}{g_c \sigma_L (\rho_L - \rho_g)} [1]
 N_D = 453.592\ \frac{g_c (\rho_L - \rho_g) D^2}{\sigma_L }
 R = \frac{v_{SL}}{v_{SG}}
 B = 0.0814 \left ( 1 - 0.554\ \ln \left (1 + \frac{730 R}{R+1} \right )  \right )
 A = -2.2314 \left ( N_V \left (1 + \frac{205}{N_D} \right )  \right )^B
 H_g = \frac{1-e^A}{R+1}
 C_L = \frac{v_{SL}}{v_{SG}+v_{SL}}

Nomenclature

NV velocity number

References

  1. 1.0 1.1 1.2 1.3 Gray, H. E. (1974). "Vertical Flow Correlation in Gas Wells". User manual for API 14B, Subsurface controlled safety valve sizing computer program. API. 
  2. Colebrook, C. F. (1938–1939). "Turbulent Flow in Pipes, With Particular Reference to the Transition Region Between the Smooth and Rough Pipe Laws"Paid subscription required. Journal of the Institution of Civil Engineers. London, England. 11: 133–156. 
  3. Moody, L. F. (1944). "Friction factors for pipe flow"Paid subscription required. Transactions of the ASME. 66 (8): 671–684. 
  4. Cite error: Invalid <ref> tag; no text was provided for refs named HB
  5. 5.0 5.1 Cite error: Invalid <ref> tag; no text was provided for refs named Lyons