Erosion Prediction Calculator

The ErosionPredictionCalculator provides sand erosion assessment for production piping and process equipment using two industry-standard methods.

Class: neqsim.pvtsimulation.flowassurance.ErosionPredictionCalculator

Standards Implemented

Standard	Method	Output
API RP 14E	Erosional velocity limit	Max allowable velocity (m/s)
DNV RP O501	Sand particle erosion model	Erosion rate (mm/yr), cumulative loss

API RP 14E - Erosional Velocity

The API RP 14E erosional velocity formula limits mixture velocity to prevent erosion:

\[V_e = \frac{C}{\sqrt{\rho_m}}\]

Where:

$V_e$ = erosional velocity (ft/s, converted to m/s internally)
$C$ = empirical constant (default 100 for continuous service)
$\rho_m$ = mixture density at flowing conditions (lb/ft3)

C-Factor Guidelines

Service	C-Factor
Continuous (default)	100
Intermittent	125
Solids-free, inhibited	150
With sand production	75-100

DNV RP O501 - Sand Erosion Model

The DNV model predicts material loss rate from sand particle impact:

\[E = K \cdot F(geometry) \cdot \dot{m}_p \cdot V_p^n \cdot f(\alpha)\]

Where:

$K$ = material constant (depends on pipe material grade)
$F$ = geometry factor (elbow, tee, choke, etc.)
$\dot{m}_p$ = sand mass flow rate
$V_p$ = particle impact velocity
$f(\alpha)$ = impact angle function

Supported Materials

Material	Typical Application
`carbon_steel`	General piping
`duplex_steel`	Moderate corrosion environments
`super_duplex`	Severe corrosion + erosion
`13cr`	Downhole tubing
`inconel`	High temperature, corrosive
`titanium`	Seawater systems
`tungsten_carbide`	Choke trim

Supported Geometries

Geometry	Typical Use
`straight_pipe`	Straight pipe sections
`elbow`	Standard pipe elbows
`tee`	Tee junctions
`blind_tee`	Dead-end tees (sand traps)
`reducer`	Pipe reducers
`choke`	Production chokes
`weld`	Girth/field welds

Usage

Basic Erosional Velocity Check

import neqsim.pvtsimulation.flowassurance.ErosionPredictionCalculator;

ErosionPredictionCalculator calc = new ErosionPredictionCalculator();
calc.setMixtureDensity(120.0);    // kg/m3
calc.setMixtureVelocity(12.0);   // m/s (actual velocity)
calc.setApiCFactor(100.0);       // Continuous service
calc.calculate();

double erosionalVelocity = calc.getErosionalVelocity();
double velocityRatio = calc.getVelocityRatio();
boolean withinLimits = calc.isWithinApiLimits();

System.out.printf("Erosional velocity: %.1f m/s%n", erosionalVelocity);
System.out.printf("Velocity ratio: %.2f%n", velocityRatio);
System.out.printf("Within API limits: %s%n", withinLimits);

Sand Erosion Assessment

ErosionPredictionCalculator calc = new ErosionPredictionCalculator();

// Flow conditions
calc.setMixtureDensity(150.0);    // kg/m3
calc.setMixtureVelocity(15.0);   // m/s

// Pipe geometry
calc.setPipeDiameter(0.1524);     // 6 inch (meters)
calc.setWallThickness(10.0);     // mm

// Sand parameters
calc.setSandRate(50.0);           // kg/day
calc.setSandParticleDiameter(0.25); // mm

// Material and geometry
calc.setPipeMaterial("carbon_steel");
calc.setGeometry("elbow");

// Design parameters
calc.setDesignLife(25.0);         // years
calc.setCorrosionAllowance(3.0);  // mm

calc.calculate();

// Results
double erosionRate = calc.getErosionRate();         // mm/yr
double cumulative = calc.getCumulativeErosion();     // mm over design life
double remaining = calc.getRemainingWallThickness(); // mm
String riskLevel = calc.getRiskLevel();              // low/medium/high/critical

System.out.printf("Erosion rate: %.4f mm/yr%n", erosionRate);
System.out.printf("Cumulative erosion (25 yr): %.2f mm%n", cumulative);
System.out.printf("Remaining wall: %.2f mm%n", remaining);
System.out.printf("Risk level: %s%n", riskLevel);

Multiple Geometry Comparison

String[] geometries = {"straight_pipe", "elbow", "blind_tee", "tee", "choke"};

for (String geometry : geometries) {
    ErosionPredictionCalculator calc = new ErosionPredictionCalculator();
    calc.setMixtureDensity(150.0);
    calc.setMixtureVelocity(15.0);
    calc.setPipeDiameter(0.1524);
    calc.setSandRate(50.0);
    calc.setPipeMaterial("carbon_steel");
    calc.setGeometry(geometry);
    calc.calculate();

    System.out.printf("%-15s  Erosion: %.4f mm/yr  Risk: %s%n",
        geometry, calc.getErosionRate(), calc.getRiskLevel());
}

JSON Output

String json = calc.toJson();
System.out.println(json);

Sand Load Defaults by Completion Type

The calculator provides default sand production parameters based on well completion type, enabling quick screening assessments without detailed sand monitoring data.

Available Completion Types

Completion	Sand Rate (g/m3)	Particle Diameter (μm)	Description
`openhole_gravel_pack`	5.0	200	Open hole with gravel pack
`cased_perforated`	15.0	250	Cased and perforated
`standalone_screen`	3.0	150	Standalone screen in open hole
`frac_pack`	8.0	180	Hydraulic fracture with gravel pack
`expandable_screen`	4.0	170	Expandable sand screen

Usage

ErosionPredictionCalculator calc = new ErosionPredictionCalculator();

// Apply defaults for a completion type
calc.applySandLoadDefaults("cased_perforated");
// Sets sandRate = 15.0 g/m3, sandParticleDiameter = 250 μm

// Get defaults without applying
ErosionPredictionCalculator.SandLoadDefaults defaults =
    calc.getSandLoadDefaults("frac_pack");
System.out.println(defaults.getSandRate());           // 8.0
System.out.println(defaults.getSandParticleDiameter()); // 180.0
System.out.println(defaults.getDescription());        // "Hydraulic fracture with gravel pack"

// List all available completion types
List<String> types = calc.getAvailableCompletionTypes();

Maximum Velocity for Corrosion Protection

In addition to erosion limits, the calculator provides a velocity limit to protect internal corrosion barriers (coatings, inhibitor films):

// Calculate maximum velocity that preserves corrosion protection
double maxVel = calc.calcMaxVelocityForCorrosionProtection(
    150.0,    // mixture density kg/m3
    0.0002    // sand concentration kg/kg (200 ppm)
);
// Typical range: 5-20 m/s depending on conditions

Flow Assurance Screening Tools - Pipeline cooldown, corrosion, scale
Emulsion Viscosity - Emulsion viscosity models

calc.calculate();
String json = calc.toJson();
System.out.println(json);

Output includes:

API RP 14E results (erosional velocity, velocity ratio, within limits)
DNV RP O501 results (erosion rate, cumulative, remaining wall)
Risk assessment (level: low/medium/high/critical)
All input parameters for traceability

Risk Assessment

The risk level is determined by the velocity ratio (actual / erosional):

Velocity Ratio	Risk Level
< 0.5	Low
0.5 - 0.8	Medium
0.8 - 1.0	High
> 1.0	Critical

Python Usage

from neqsim import jneqsim

ErosionPredictionCalculator = jneqsim.pvtsimulation.flowassurance.ErosionPredictionCalculator

calc = ErosionPredictionCalculator()
calc.setMixtureDensity(150.0)
calc.setMixtureVelocity(15.0)
calc.setPipeDiameter(0.1524)
calc.setSandRate(50.0)
calc.setPipeMaterial("carbon_steel")
calc.setGeometry("elbow")
calc.setDesignLife(25.0)
calc.setCorrosionAllowance(3.0)
calc.calculate()

print(f"Erosion rate: {calc.getErosionRate():.4f} mm/yr")
print(f"Risk: {calc.getRiskLevel()}")
print(calc.toJson())

Erosion Prediction Calculator

Standards Implemented

API RP 14E - Erosional Velocity

C-Factor Guidelines

DNV RP O501 - Sand Erosion Model

Supported Materials

Supported Geometries

Usage

Basic Erosional Velocity Check

Sand Erosion Assessment

Multiple Geometry Comparison

JSON Output

Sand Load Defaults by Completion Type

Available Completion Types

Usage

Maximum Velocity for Corrosion Protection

Related Documentation

Risk Assessment

Python Usage

Related Documentation