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Sensitivity, Monte Carlo, contour, surface

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89 published calculators available for analysis.

Reservoir EngineeringPermeability and Flow

Buckley-Leverett Breakthrough Pore Volumes

tD,bt=(dfwdSw)shock−1t_{D,bt} = \left(\frac{df_w}{dS_w}\right)_{shock}^{-1}
Open analysis
Reservoir EngineeringPermeability and Flow

van Genuchten-Mualem Wetting Relative Permeability

krw=Se[1−(1−Se1/m)m]2k_{rw}=\sqrt{S_e}\left[1-(1-S_e^{1/m})^m\right]^2
Open analysis
Reservoir EngineeringPermeability and Flow

Brooks-Corey Nonwetting Relative Permeability

krn=(1−Se)2[1−Se1+2/λ]k_{rn}=(1-S_e)^2\left[1-S_e^{1+2/\lambda}\right]
Open analysis
Reservoir EngineeringPermeability and Flow

van Genuchten Nonwetting Relative Permeability

krn=1−Se(1−Se1/m)2mk_{rn}=\sqrt{1-S_e}\left(1-S_e^{1/m}\right)^{2m}
Open analysis
Reservoir EngineeringPVT and Rock-Fluid Properties

Capillary Number

Nc=μw⋅V⋅0.304886400⋅σowN_c = \frac{\mu_w \cdot V \cdot 0.3048}{86400 \cdot \sigma_{ow}}
Open analysis
Reservoir EngineeringPVT and Rock-Fluid Properties

Characteristic Time for Linear Diffusion in Reservoirs

τ=Cu(Φ⋅βf+βr)⋅μ⋅l2k\tau = C_u \frac{(\Phi \cdot \beta_f + \beta_r) \cdot \mu \cdot l^2}{k}
Open analysis
Reservoir EngineeringPVT and Rock-Fluid Properties

Cumulative Oil Production – Undersaturated Oil Reservoirs

Np=N⋅ce⋅(BoiBo)⋅ΔPNp = N \cdot c_e \cdot \left( \frac{B_{oi}}{B_o} \right) \cdot \Delta P
Open analysis
Reservoir EngineeringPVT and Rock-Fluid Properties

API Gravity

API=141.5SGo−131.5API = \frac{141.5}{SG_o} - 131.5
Open analysis
Reservoir EngineeringPressure Transient Analysis

Skin Factor from Pressure Transient Semilog Analysis

s=1.151(Rp−L+3.23)Rp=Δp1hr/mL=log⁡10(kϕμctrw2)\begin{aligned}s&=1.151(R_p-L+3.23)\\R_p&=\Delta p_{1hr}/m\\L&=\log_{10}\left(\frac{k}{\phi\mu c_tr_w^2}\right)\end{aligned}
Open analysis
Reservoir EngineeringPressure Transient Analysis

Dimensionless Pressure for Linear Flow Constant Rate General Case

pD=kA(pi−p)141.2qBμp_D=\frac{k\sqrt{A}(p_i-p)}{141.2qB\mu}
Open analysis
Reservoir EngineeringPressure Transient Analysis

Radius of Investigation

ri=0.0359ktϕμctr_i=0.0359\sqrt{\frac{kt}{\phi\mu c_t}}
Open analysis
Reservoir EngineeringPressure Transient Analysis

Pseudosteady-State Dimensionless Pressure Drop for Horizontal Well

PD=2πtDA+0.5ln⁡(A4(L/2)2)+0.5ln⁡(2.2458CAh)+1.385P_D=2\pi t_{DA}+0.5\ln\left(\frac{A}{4(L/2)^2}\right)+0.5\ln\left(\frac{2.2458}{C_{Ah}}\right)+1.385
Open analysis
Reservoir EngineeringPressure Transient Analysis

Fracture Conductivity During Bilinear Flow

FC=[44.1QμBmbfh(ϕμctk)0.25]2F_C=\left[\frac{44.1 Q \mu B}{m_{bf} h (\phi \mu c_t k)^{0.25}}\right]^2
Open analysis
Reservoir EngineeringUnconventional Reservoirs

Tight Gas Pore Volume from Squared-Pressure Decline

PV=28.27Tμg,avgzavgμgicti(Pi2−Pwf2)qiDiPV=\frac{28.27T\mu_{g,avg}z_{avg}}{\mu_{gi}c_{ti}(P_i^2-P_{wf}^2)}\frac{q_i}{D_i}
Open analysis
Reservoir EngineeringMaterial Balance and Production

Cumulative Gas Production – Tarner’s Method

Gp=N⋅[(Rsi−Rs)−Boi−BoBg]−Np⋅(BoBg−Rs)Gp = N \cdot \left[ (Rsi - Rs) - \frac{Boi - Bo}{Bg} \right] - Np \cdot \left( \frac{Bo}{Bg} - Rs \right)
Open analysis
Reservoir EngineeringMaterial Balance and Production

Original Oil in Place from General Oil Material Balance

N=F−WeEo+mEg+EfwN = \frac{F-W_e}{E_o+mE_g+E_{fw}}
Open analysis
Reservoir EngineeringMaterial Balance and Production

Gas Produced by Gas Expansion

Gp=43560Ahϕ(1−Swi)(1Bgi−1Bg)G_p=43560Ah\phi(1-S_{wi})\left(\frac{1}{B_{gi}}-\frac{1}{B_g}\right)
Open analysis
Reservoir EngineeringWell Performance

Joshi Horizontal Well Productivity Index

Jh=0.00708khhμoBo[ln⁡Rh+βhLln⁡(βh2rw)+s]J_h=\frac{0.00708k_hh}{\mu_oB_o\left[\ln R_h+\frac{\beta h}{L}\ln\left(\frac{\beta h}{2r_w}\right)+s\right]}
Open analysis
Reservoir EngineeringWell Performance

Craft and Hawkins Vertical Well Critical Coning Rate

qo=0.007078koh(pws−pwf)μoBoln⁡(re/rw)PRq_o=\frac{0.007078k_oh(p_{ws}-p_{wf})}{\mu_oB_o\ln(r_e/r_w)}PR
Open analysis
Reservoir EngineeringReservoir Volumetrics

Original Gas in Place - Volumetric Method

G=43560Ahϕ(1−Swi)BgiG = \frac{43560 A h \phi (1 - S_{wi})}{B_{gi}}
Open analysis
Reservoir EngineeringPVT Properties

Gas Formation Volume Factor

Bg=0.02827zTPB_g = 0.02827 \frac{zT}{P}
Open analysis
Reservoir EngineeringPVT Properties

Gas Expansion Factor from Formation Volume Factor

Eg=35.37PzTE_g = 35.37 \frac{P}{zT}
Open analysis
Reservoir EngineeringMaterial Balance

Water Influx Constant for van Everdingen-Hurst Aquifer

B=1.119ϕctre2hfB=1.119\phi c_tr_e^2hf
Open analysis
Reservoir EngineeringMaterial Balance

van Everdingen-Hurst Single-Step Water Influx

We=BΔpWeDW_e=B\Delta p W_{eD}
Open analysis