GasOilWater Apps 

Home  AGA3  ISO5167  GasLeak  Restriction Orifice  GOWProp  WatGas  GOSep  Contact  
Easy to use engineering apps for the oil and gas industry  designed for practical field applications. Apps have been tested and proven both on offshore and onshore oil and gas installations. Written as Excel macros, requiring Microsoft Excel with 'Macro' enabled (Excel 2007 and newer). Download free apps, demo apps or purchase full version apps from $4.99 to $9.99 each. 
Available Apps  
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AGA3 calculates size, flowrate or pressure drop for gas and liquid flow orifice meters based on ANSI/API25301991, Part 3 (AGA3).  Download Free Demoversion 

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ISO5167 calculates size, flowrate or pressure drop for gas and liquid flow orifice meters based on International Standard ISO51672:2003. 


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GasLeak estimates gasleak rates from piping based on restriction orifice calculations as per R.W. Miller's "Flow Measurement Handbook", assuming critical flow across the leak point.  
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Restrict_Ori calculates size and flowrates for gas and liquid restriction orifice meters based on R.W. Miller's "Flow Measurement Handbook".  
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GOWProp calculates physical properties (PVT) of Gases (Natural Gas, Air and Nitrogen) and Liquids (Oil, Water, MeOH, MEG, DEG and TEG) based on published correlations. 


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WatGas performs calculations for:  Hydrate Formation Conditions  Water Content of Natural Gases  MeOH/Glycol Inhibition Requirements  Solid CO2 Formation Conditions 

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GOSep performs flash calculations through two Oil/Gas separator stages optimize liquid recovery depending on pressure/temperature at each separator stage. Free App.  
GOWDoc is the free documentation for the listed programs with correlations included (PDFfile).  
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AGA3 Orifice Calculations The velocity of approach factor is defined as: Fgr= Specific gravity factor 

ISO5167 Orifice Calculations ISO5167 will size orifice plates for given design conditions, find pressure drop for a given flow, or flow for a given pressure drop. The standard (ISO5167:2003) is originally designed for gas orifices. In this program the standard is also used for liquid orifices. Gas calculations are performed for Natural Gas, Nitrogen and Air. For liquid orifice calculations, the options are Crude Oil, Water, Methanol, Monoethylene glycol (MEG), Diethylene glycol (DEG) and Triethylene glycol (TEG). Input requirements are specific gas gravity, temperature and pressure for gas calculations. You can also give molefractions of N2, CO2 and H2S for sour gas calculations. The AGA8 equation is used for calculating Zfactor (compressibility factor) for natural gases, and the RedlichKwong equation of state for Nitrogen and Air. For oilcalculations you have to enter specific oil gravity, temperature and pressure. It is also recommended to give molecular weight of oil. For watercalculations the input requirements are salinity, temperature, and pressure. It is assumed that all dissolved solids for water are expressed as equivalent sodium chloride concentration. The result will be an orifice specification sheet giving the necessary data for design of an orifice or evaluating an existing orifice. The results will contain a few factors that you should know: The velocity of approach factor is defined as: Ev = 1/(Sqrt(1Beta^4)) The flow coefficient, Alpha, is defined as: Alpha = Ev * Cd and orifice to pipe diameter ratio is given as: Beta = OD/PID ISO51672: 2003 ( ISO5167) The basic flow equation is: Qm = C*E*Eps*Pi/4*OD^2*Sqrt(2*dP*Roh) where Qm = Mass flow rate (kg/s) C = Discharge coefficient = Alpha/E E = Velocity of approach factor = 1/(Sqrt(1Beta^4)) Eps = Expansion factor due to pressure drop Pi = 3.14159 OD = Orifice diameter at actual flowing conditions dP = Differential pressure across orifice Roh = Density of flowing fluid measured at upstream tap Home  Download 

GasLeak Calculations Gas leak rate calculations are based on the assumption that the pressure difference across the leakpoint (hole) is large enough to cause critical flow across the hole/crack. The calculated flowrates are based on restriction orifice correlations. This means that sonic velocity exists at the orifice throat, and further decrease in the downstream pressure will not increase the mass flow rate. The flowrate calculated is only correct if the upstream and downstream pressures remain constant. If a blowdown situation occurs, the flowrate drops significantly due to the reduction in the upstream pressure and will be zero when pressures are equalized across the leakpoint. In this case, the program only calculates the initial flowrate. Restriction orifice calculations in this program are performed according to R. W. Miller's "Flow Measurement Engineering Handbook". The basic mass flow rate equation is: Qm = 1335.485*C*d^2*Ycr*Sqrt(Z*Roh*Ftp*P) where Qm = mass flow rate, lbm /h C = critical discharge coefficient d = orifice diameter at flowing conditions, in Yrc = critical flow function Ftp = total pressure correction factor to adjust for difference between static pressure read at the pipe wall (Manometer) and total pressure of the fluid and Z, Roh and P are measured at flowing upstream conditions For Betaratios less than 0.5 the total pressure correction factors are approximated by: Ftp = {1  k/2*[2/(k+1)]^[(k+1)/(k1)] * Beta^4}^(1) Ycr = {k/Z*[2/(k+1)]^[(k+1)/(k1)]}^0.5 where k = isentropic coefficient at flowing conditions Assuming steady isentropic flow, critical flow (choked flow) occurs when: P2/P1/Ftp < [2/(k+1)]^[k/(k1)] where P1 = pressure upstream orifice and P2 = pressure downstream orifice By assuming sharpedged orifices with plate thickness to bore diameter between 1 and 6 the discharge coefficient is a constant given in the program as: C = 0.83932 Program Gas_Leak will check if flow is critical. If flow is found to be subcritical, the program will simply perform normal orifice calculations based on ISO51672: 2003, assuming a flangetapped orifice, and basic flow equation given above as for the ISO5167 calculation. Home  Download 

Restriction Orifice Calculations Restriction orifice calculations in this program are performed according to R. W. Miller's "Flow Measurement Engineering Handbook". Gas restriction orifices are calculated based on critical flow in the orifice. This means that sonic velocity exists at the orifice throat, and further decrease in the downstream pressure will not increase the mass flow rate. For critical flow the basic mass flow rate equation is: Qm = 1335.485*C*d^2*Ycr*Sqrt(Z*Roh*Ftp*P) where Qm = mass flow rate, lbm /h C = critical discharge coefficient d = orifice diameter at flowing conditions, in Yrc = critical flow function Ftp = total pressure correction factor to adjust for difference between static pressure read at the pipe wall (Manometer) and total pressure of the fluid and Z, Roh and P are measured at flowing upstream conditions For Betaratios less than 0.5 the total pressure correction factors are approximated by: Ftp = {1  k/2*[2/(k+1)]^[(k+1)/(k1)] * Beta^4}^(1) Ycr = {k/Z*[2/(k+1)]^[(k+1)/(k1)]}^0.5 where k = isentropic coefficient at flowing conditions Assuming steady isentropic flow, critical flow (choked flow) occurs when: P2/P1/Ftp < [2/(k+1)]^[k/(k1)] where P1 = pressure upstream orifice and P2 = pressure downstream orifice By assuming sharpedged orifices with plate thickness to bore diameter between 1 and 6 the discharge coefficient is a constant given in the program as: C = 0.83932 Liquid choked flow occurs if a cavitation barrier exists within an orifice. Only upstream pressure increases can increase flowrates. Thick squareedged orifices are used as they are inexpensive. The sizing and flowrate equation used for liquids is: Qm = C*E*PI/4*d^2*Sqrt(2*DeltaP*Roh1) where DeltaP = P  Pv = upstream pressure minus vapor pressure of liquid, Pa Roh1 = 1.0 = expansion factor for liquids Other factors are defined above as part of the Gas Restriction Orifice calculations. Assuming squareedged orifices with plate thickness to bore diameter less than 6 with a minimum of 0.125 in (3 mm), the liquid restriction orifice constant is : C = 0.6 Home  Download 

GasOilWater Properties Program GOWProp is a Physical Properties program that calculates PVT properties of gas, oil, and water  with your choice of calculation methods. Pick from a selection of standard equations for calculating certain properties. More than 12 properties are calculated and the results include a pressure depletion table of the various properties and will plot the output on screen. U.S. and SI Units. Oil properties are calculated based on a blackoil model. In fluidproperty terms the blackoil model employs 2 pseudocomponents: 1) "OIL" defined as produced oil at stock tank conditions 2) "GAS" defined as produced separator gas The basic assumption is that gas may dissolve in the oil phase, but oil will not dissolve in the gas phase. For mixtures of heavy oil and light components this is a reasonable assumption, but is a misleading assumption for mixtures of light and intermediate components. Natural gas Nitrogen Air Liquids: Oil Water Methanol/Water mixtures (MeOH) Monoethylene glycol/Water mixtures (MEG) Diethylene glycol/Water mixtures (DEG) Triethylene glycol/Water mixtures (TEG) GOWProp will let you choose between SIunits (metric) or Customary units (US). The gas property routine calculates:  Molecular weight  Density  Compressibility  Gas formation volume factor  Zfactor (gas deviation factor)  Viscosity  Thermal conductivity  Specific heat  Ideal isentropic coefficient, Cp/Cv  Real isentropic coefficient, k  Pseudo Critical properties  Pseudo Reduced properties The liquid property routine calculates:  API gravity (for oil only)  Density  Compressibility  Formation volume factor (oil and water only)  Solution gasliquid ratio (oil and water only)  Bubble point pressure (oil only)  Viscosity  Thermal conductivity  Surface tension  Specific heat  Pseudo Critical properties  Pseudo Reduced properties Home  Download 

WaterGas Physical Properties WatGas calculates WaterNatural Gas interaction properties, including the following PVTproperties:  Hydrate formation calculations  Water content predictions of natural gases  Inhibitor quantities (methanol/glycols) to avoid hydrate problems in pipelines The program handles gases with known compositions and noncompositional gases (only gas gravity is needed). Note that the compositional model is more reliable than the noncompositional model, although they give similar results. Condensed water may form water slugs, which will tend to decrease flow efficiency and increase pressure drop in a line. Presence of free water in pipeline systems may also cause corrosion. If carbon dioxide and/or hydrogen sulfide are present, the gases may form carbonic acid and sulphuric acid respectively if dissolved in water. 

GasOil Separator Flash Calculations
Program GOSep performs flash calculations for gas/oil separators to optimize liquid recovery. The program performs vaporliquid equilibrium calculations for two stages of separation and Stock Tank conditions (Standard Conditions), defined in the program as 14.73 psia and 60 °F. Equilibrium ratios (Kvalues) are used for calculating compositions of gas and liquid phases at given temperatures and pressures at each stage. Normally an equation of state (EOS) is used for predicting equilibrium ratios, and is a function of composition, pressure and temperature. Based on the fact that compositional effects on equilibrium ratios are small below about 1000 psia, Standing developed a correlation for calculating equilibrium ratios based on data reported by Katz and Hachmuth. The correlation gives the following equation for each component: T = temperature, deg R 

Updated Dec 1, 2016  Copyright © Norcraft  2016 