🛢️ Pipeline Linepack Inventory

Calculate high-pressure gas transmission pipeline linepack inventory (Sm³ and tons), AGA average line pressure, usable draft buffer, and autonomy time.

⚡ Fortran 90 Engine Double Precision (IEEE 754) ✓ ISO / ASME Validated

📊 Solver Telemetry ● ACTIVE

👁️ Consultations 44

⚡ Calculs faits 35

💾 Téléchargements 421 📦 Code Fortran 4.4 KB

📅 Mise en service Jun 2026

⏱️ Latence < 1 ms

🛢️ High-Pressure Transmission Pipeline Linepack & Dynamic Storage

Real-time visual simulation of pressure gradient decay P(x) & in-situ gas mass inventory

📝 Configuration & Presets

🔥 36" Trunkline (150 km) 🏙️ 16" Feeder (40 km) 🌊 42" Offshore (220 km) 🏭 10" Plant Loop (12 km)

📐 Pipeline Dimensions & Pressures

Pipeline Length L [km]:

Inside Diameter D_i [mm]:

Inlet Pressure P₁ [bar absolute]:

Outlet Pressure P₂ [bar absolute]:

💨 Gas Properties & Storage Limits

Average Gas Temperature T [°C]:

Minimum Delivery Pressure P_min [bar a]:

Molecular Weight MW [g/mol]: Methane: 16.04, Natural Gas blend: 16.5–18.0

Compressibility Factor Z:

Consumer Demand Draw Rate [Sm³/h]: Used to calculate pipeline autonomy duration

AGA Linepack Formulations:
• Average Pressure: P̄ = ⅔ [ P₁ + P₂² / (P₁ + P₂) ]
• Standard Inventory: V_std = V_geom · (P̄ / P_std) · (T_std / T̄) · (1/Z)
• Usable Buffer: V_usable = V_std(P̄) − V_std(P_min)
• Autonomy Time: τ = V_usable / Q_demand [hours]

📊 Linepack Inventory Results

📊 Output Summary
💾 Fortran Source

Total Standard Gas Inventory (Linepack)

0.18 Million Sm³

In-Situ Gas Mass = 0 Metric Tons

P̄ = 33.08 bar(a)

Usable Draft Buffer Stock 71 kSm³ Above P_min = 20.0 bar

Pipeline Autonomy Buffer 1.8 hours At demand 40,000 Sm³/h

Pipeline Geometric Volume 5,027 m³ 40.0 km × DN 400

Pressure Ratio (P₁/P₂) 1.60 ΔP = 15.0 bar

📈 Pressure Gradient Profile P(x) along Pipeline

📈 Standard Gas Linepack vs Inlet Pressure P₁

=================================================================
 THERMOFLUIDCALC — PIPELINE LINEPACK INVENTORY REPORT
=================================================================
Case Title                 : Regional Gas Distribution Feeder Pipeline (16", 40 km)
Pipeline Length (L)        : 40.00 km
Inside Diameter (Di)       : 400.0 mm (0.4000 m)
Geometric Pipe Volume      : 5,026.55 m3
Inlet / Outlet Pressures   : 40.00 / 25.00 bar(a)
AGA Average Pressure (P_avg): 33.077 bar(a)
-----------------------------------------------------------------
TOTAL STANDARD LINEPACK    : 178,357.1 Sm3 (0.178 MSm3)
IN-SITU GAS MASS           : 0.12 Metric Tons
USABLE DRAFT BUFFER STOCK  : 70,513.3 Sm3 (Above 20.0 bar)
AUTONOMY BUFFER DURATION   : 1.76 hours (0.07 days)
=================================================================

📘 Calculation Methodology & AGA Formulations

Non-Linear Pressure Profile P(x)

Due to gas compressibility and expansion, the pressure decay along a transmission pipeline is parabolic rather than linear:

                    P(x) = √[ P₁² − (x/L)(P₁² − P₂²) ]
                

Dynamic Linepack Storage Capacity

Transmission pipelines act as large storage reservoirs ("virtual gas holders"), allowing operators to absorb daily peak demand swings by packing or drafting the line.

Key Engineering Assumptions

Isothermal steady-state gas transmission.
Standard conditions evaluated at $15^\circ\text{C}$ and $1.01325\,\text{bar a}$ (ISO 13443).
Compressibility factor $Z$ computed across average pipeline conditions.

ThermoFluidCalc Engineering Report