Wellbore Genius

PKN vs Nordgren — pressure-curve comparison Method

Side-by-side plots of the corrected Newton-runner PKN wellbore pressure and the Nordgren analytical reference p_net = E'·w_w / (2·h_f) with w_w ∝ t^(1/5), computed from the same inputs. The residual chart below tracks log₁₀(w_num / w_an) against the current pkn-length registry tolerance ±0.15.

Early-time asymptote (default ON) blends the raw kernel to Nordgren when L_kernel ≤ dx, so the historical ~0.18 log-unit gap at t = 0.5 s now collapses to ≈ 0. Full write-up at /solver-spec §5 · richer form with thermal + STP at /pkn-early-time.

Tolerance override (audit lens)

Reproduce older results by widening the local pkn-length gate. Default remains 0.15; the DFIT registry and CI are never touched.

Enable override

Override value [log₁₀]

Active tol 0.15

Inputs

Field units — converted internally to SI.

Injection rate [bpm]

Plane-strain modulus E' [Mpsi]

Viscosity μ [cP]

Fracture height h_f [ft]

Reservoir pressure [psi]

t_min [s]

t_max [s]

Samples [—]

Audit summary

Log residual gate: max |log₁₀(w_num/w_an)| vs 0.15

fail

Earliest log residual

-0.9100

Max |log residual|

0.9100

Median rel p_net residual

0.3177

Headroom (1 − max/tol)

-5.067

Nordgren analytical (reference)

p_well = p_res + E'·w_w/(2·h_f), w_w ∝ t^(1/5)

Newton runner (corrected)

earlyTimeAsymptote ON — blends to Nordgren when L_kernel ≤ dx

Per-sample log residual vs tolerance

log₁₀(w_num / w_an); shaded band = ±0.15 pkn-length tol.