neqsim-near-well-and-injectivity

Derives productivity and injectivity indices from OPM Flow reservoir models and NeqSim black-oil PVT tables.

4|2|Updated May 31, 2026
One-click install
npx skills add https://github.com/equinor/neqsim-community-skills --skill neqsim-near-well-and-injectivity-equinor
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: neqsim-near-well-and-injectivity
Source: https://github.com/equinor/neqsim-community-skills/tree/main/skills/subsurface/near-well-and-injectivity
Command: npx skills add https://github.com/equinor/neqsim-community-skills --skill neqsim-near-well-and-injectivity-equinor

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires pyscal, resdata, numpy, neqsim.

What problem does it solve? Productivity and injectivity indices are often assumed without derivation, and NeqSim alone cannot answer what the rock around a well will give or take. This Skill derives those indices from reservoir physics, converts NeqSim compositional fluids into black-oil PVT tables that OPM Flow accepts, and hands the resulting inflow relationship back to NeqSim wellbore and process models. ## Core Features & Use Cases - Black-oil PVT conversion: Converts a NeqSim compositional fluid into validated PVTO, PVDG, PVTW (or PVTG/PVDO for gas condensates) deck sections, checking Rs monotonicity, Bo trends, and agreement with measured PVT. - Reservoir simulation with OPM Flow: Builds Eclipse-format radial or sector decks with pyscal-generated SWOF/SGOF tables and logarithmic near-well grids, then reads WPI/CWPI productivity indices back with resdata. - Injectivity and voidage analysis: Evaluates the endpoint mobility ratio to determine whether injectivity improves or declines as a water bank develops, and checks injectors against the voidage requirement. - Use Case: A gas condensate field must match a mandated production profile. Use this Skill to compute the dropout curve, build a VAPOIL deck with PVTG/PVDO tables, size the reservoir volume backwards from the recoverable gas, and verify well deliverability in OPM Flow. ## Quick Start Ask the agent to derive a productivity index for a well by converting a NeqSim fluid to a black-oil table and running an OPM Flow radial model.

Frequently Asked Questions about neqsim-near-well-and-injectivity

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I convert a NeqSim compositional fluid to a black-oil PVT table?▼

Use NeqSim's BlackOilConverter.convert with the fluid, reservoir temperature, and a pressure grid to produce Rs, Bo, and Bg tables. Validate that Rs increases monotonically to the bubble point and Bo matches measured PVT before writing PVTO and PVDG deck sections.

How do I derive a productivity index with OPM Flow?▼

Build an Eclipse-format radial or sector deck with pyscal-generated SWOF/SGOF tables and a logarithmic near-well grid, then run OPM Flow. Request WPI and CWPI in the SUMMARY section and read the productivity index back with resdata.

Can OPM Flow run on Windows?▼

OPM Flow is Linux software, so on Windows it requires WSL2 or a Docker container based on Ubuntu with the OPM PPA packages. It also aborts silently under a non-English locale, so set LANG and LC_ALL to C.UTF-8.

Why does OPM Flow reject my PVTO table?▼

Flow requires Bo strictly decreasing with pressure within each undersaturated branch, which raw converter output violates because saturated Bo rises with pressure. Build each branch from an oil compressibility fitted to the genuinely undersaturated rows instead of reusing saturated rows.

When should I use vaporised oil instead of black oil for a gas condensate?▼

Compute the retrograde dropout curve first; if peak liquid dropout exceeds roughly 2-3 volume percent, a dry-gas PVDG model is indefensible. Use VAPOIL with PVTG and PVDO tables to represent dropout and condensate banking without the PVTO monotonicity constraints.

What are the limitations of this near-well reservoir modeling approach?▼

OPM Flow is used as a black-oil simulator, so compositional effects like miscible displacement and CO2 solubility are out of scope. Without measured PVT or SCAL data, derived indices are analogues, and near-well models say nothing about aquifer support or field-wide voidage.