Page 211 - Formulas and Calculations for Petroleum Engineering

204 Formulas and calculations for petroleum engineering

4.58 Perforation length in formation 228 4.89 Sucker rod—Peak polished rod load 244
4.59 Perforation penetration ratio (formation of interest/ 4.90 Suspension property of static fluids (completion
reference formation) 229 and workover fluids) 245
4.60 Perforation skin factor 229 4.91 Tangential annular flow of a power law fluid 245
4.61 Pore growth function (acidizing) 230 4.92 Temperature at choke outlet 246
4.62 Pressure drop across perforations in gas wells 230 4.93 The z component of the force of the fluid on the
4.63 Pressure drop across perforations in oil wells 231 wetted surface of the pipe 246
4.64 Pressure loss due to perforations during hydraulic 4.94 Total skin in partially depleted wells for
fracturing 232 a buildup test 246
4.65 Pressure loss due to perforations during hydraulic 4.95 Velocity distribution in the annular slit of a
fracturing—2 232 falling-cylinder viscometer 247
4.66 Principal stress due to petro-static pressure 4.96 Velocity distribution in the narrow annular region
(hydraulic fracturing) 232 in annular flow with inner cylinder moving axially 247
4.67 Productivity index (for generating composite IPR 4.97 Velocity distribution of flow through an annulus 248
curve) 233 4.98 Velocity of fluid in annulus 248
4.68 Productivity ratio 233 4.99 Velocity of fluid in pipe 249
4.69 Productivity ratio calculation of a hydraulically- 4.100 Viscous force acting on the rod over the narrow
fractured formation 234 annular region 249
4.70 Pseudo skin factor due to partial penetration 4.101 Volume capacity of pipe 250
(Brons and Marting method) 234 4.102 Volume of fluid loss per unit area measured in a
4.71 Pseudo-skin factor due to partial penetration dynamic test (acidizing) 250
(Yeh and Reynolds correlation) 235 4.103 Volume of fluid loss per unit area measured in a
4.72 Pseudo-skin factor due to partial penetration (Odeh static test (acidizing) 250
correlation) 236 4.104 Volume of rock dissolved per unit volume of acid
4.73 Pseudo-skin factor due to partial penetration (acidizing) 251
(Papatzacos correlation) 236 4.105 Water quantity that dilutes the original brine with
4.74 Pseudo-skin factor due to perforations 237 assumed density (two-salt systems) 251
4.75 Quantifying formation damage and improvement 238 4.106 Weight of crystalline CaCl 2 and CaBr 2 salt addition
4.76 Recommended underbalanced environment for to brine (two-salt systems) 252
perforation 239 4.107 Well flowing pressure (line-source solution by
4.77 Reynolds number for acid flow into the fracture including skin factor) 252
(acidizing) 239 4.108 Well flowing pressure under pseudo-steady
4.78 Reynolds number for fluid loss (acidizing) 239 state flow for non-circular reservoirs 253
4.79 Sand weight needed to refill a hydraulically 4.109 Wellbore pressure loss due to friction during
fractured reservoir volume 240 hydraulic fracturing (laminar flow) 253
4.80 Shape factor expressed as skin factor for vertical 4.110 Wellbore pressure loss due to friction during
wells 240 hydraulic fracturing (turbulence flow) 254
4.81 Single-phase gas flow (subsonic) 240 4.111 Wellbore storage 254
4.82 Single-phase liquid flow through choke 241 4.112 Wellbore storage due to fluid level 254
4.83 Skin factor 241 4.113 Wellhead pressure (multiphase flow across the
4.84 Skin factor by Hawkins method 242 choke) 255
4.85 Skin factor due to partial penetration 242 4.114 Workover operations (maximum allowed tubing
4.86 Skin factor due to reduced crushed-zone permeability 243 pressure) 255
4.87 Skin factor for a deviated well 243 4.115 Young modulus by using sonic travel time (acidizing) 256
4.88 Slope of semilog plot for bottom-hole flowing
pressure vs time for drawdown test 244

4.1 Acid penetration distance (acidizing)
Input(s)

w: Average Fracture Width (ft)
L aD : Dimensionless Acid Penetration Distance (dimensionless)
N Re : Reynolds Number (dimensionless)
N Re *: Reynolds Number for Fluid Loss (dimensionless)