News – VFP Tables The Quiet Place That Decides Whether Your Model Works
Vertical Flow Performance Tables: The Quiet Piece That Decides Whether Your Model Works
01 February 2026
Authors: Stein Erik Berthelsen , Pandion Energy and Mathias Lia Carlsen , whitson
There are a lot of things in petroleum engineering that get attention. Reservoir models. Decline curves. Forecasts with lots of decimals.
Vertical Flow Performance tables rarely make that list.
And yet, if you have ever tried to connect a reservoir model to an integrated asset model, you already know this: if your VFP tables are off, everything downstream becomes harder to interpret. Production forecasts can change significantly when arrival pressure becomes the limiting factor, making accurate pressure drops from the VFP tables essential.
This post is about why VFP tables (sometimes called VLP or TPR tables, depending on terminology and software) deserve more attention than they usually get, and how Pandion Energy approaches them as a core part of their modeling workflow.
First, what are we actually talking about?
VFP, or Vertical Flow Performance, describes the pressure losses from bottomhole to wellhead as a function of rates, fluid properties and completion pipes (aka wellbore configurations). VFP is interchangeably also known as VLP (Vertical Lift Performance) or TPR (Tubing Performance Relationship). All three terms describe the same underlying physics, differing only in naming convention.
At its core, a VFP table answers one question:
Given a certain liquid rate, GOR, WOR, tubing configuration, lift method and tubing head pressure, what bottomhole pressure corresponds to this operating point?
Gravity. Friction. Acceleration.
Conceptually the full picture, that is 😉.
Despite this simplicity, VFP tables sit at a critical interface: they translate reservoir behavior into something surface networks and facility models can work with. Small inconsistencies here could propagate quickly for the full asset performance.
Unfortunately, VFP calculations are not straightforward. Complex. Think of three-phase flow, flow regimes, slippage, viscosities, densities. All varying along the well path together with temperature and pressures. What comes in handy is the advanced calculations performed by special software to create VFP tables.
Offshore Norway sets a high bar for VFP tables
Pandion Energy operates in production environments that naturally put pressure on wellbore and network modeling.
Multiple reservoirs tied back to shared infrastructure. Subsea wells. Long flowlines. Gas lift almost a standard operating mode. Injection schemes running in parallel. Permeabilities spanning several orders of magnitude.
Even if VFPs, in naming and in its original thinking, describe pressure drops in the tubing, the very same concept of using VFP tables applies to pressure drop in flowlines at surface or seabed. Sometimes the VFP tables are then called Pipeline-VFP.
In this context, VFP tables are not a secondary output. They are required inputs for:
When multiple wells share infrastructure, the accuracy of VFP tables for the overall production system becomes just as important, if not more so, than accuracy at the single-well level.
The importance of the unstable flow region
One aspect of VFP behavior that deserves special attention is the unstable flow region at low rates.
This is the regime where liquid loading, intermittent flow, and changing flow patterns dominate the pressure response. On a VFP curve, this often shows up as a non-monotonic relationship between rate and bottomhole pressure.
This region plays a role in:
How this region is represented in VFP tables has a direct impact on well operability in coupled models. It is also crucial to plan artificial lift for well kick-starting when liquid loading may become an issue.
In the North Sea this phenomenon typically plays a part for depleted fields, or fields with high watercut. Some examples: Naturally Huff-n-Puff producers in low permeable depleted reservoirs, depleted rich gas-condensate fields, and fields with high watercut. Special attention should be put here because many wells spend meaningful time in this part of the operating envelope.
Making VFP tables explicit and consistent
A key principle is that VFP tables should be generated with clear and explicit assumptions.
That means being deliberate about:
The goal is not complexity for its own sake, but transparency. When VFP tables are explicit, it becomes much easier to understand why a coupled model behaves the way it does.
There are a lot of things in petroleum engineering that get attention. Reservoir models. Decline curves. Forecasts with lots of decimals.
Vertical Flow Performance tables rarely make that list.
And yet, if you have ever tried to connect a reservoir model to an integrated asset model, you already know this: if your VFP tables are off, everything downstream becomes harder to interpret. Production forecasts can change significantly when arrival pressure becomes the limiting factor, making accurate pressure drops from the VFP tables essential.
This post is about why VFP tables (sometimes called VLP or TPR tables, depending on terminology and software) deserve more attention than they usually get, and how Pandion Energy approaches them as a core part of their modeling workflow.
First, what are we actually talking about?
VFP, or Vertical Flow Performance, describes the pressure losses from bottomhole to wellhead as a function of rates, fluid properties and completion pipes (aka wellbore configurations). VFP is interchangeably also known as VLP (Vertical Lift Performance) or TPR (Tubing Performance Relationship). All three terms describe the same underlying physics, differing only in naming convention.
At its core, a VFP table answers one question:
Given a certain liquid rate, GOR, WOR, tubing configuration, lift method and tubing head pressure, what bottomhole pressure corresponds to this operating point?
Gravity. Friction. Acceleration.
Conceptually the full picture, that is 😉.
Despite this simplicity, VFP tables sit at a critical interface: they translate reservoir behavior into something surface networks and facility models can work with. Small inconsistencies here could propagate quickly for the full asset performance.
Unfortunately, VFP calculations are not straightforward. Complex. Think of three-phase flow, flow regimes, slippage, viscosities, densities. All varying along the well path together with temperature and pressures. What comes in handy is the advanced calculations performed by special software to create VFP tables.
Offshore Norway sets a high bar for VFP tables
Pandion Energy operates in production environments that naturally put pressure on wellbore and network modeling.
Multiple reservoirs tied back to shared infrastructure. Subsea wells. Long flowlines. Gas lift almost a standard operating mode. Injection schemes running in parallel. Permeabilities spanning several orders of magnitude.
Even if VFPs, in naming and in its original thinking, describe pressure drops in the tubing, the very same concept of using VFP tables applies to pressure drop in flowlines at surface or seabed. Sometimes the VFP tables are then called Pipeline-VFP.
In this context, VFP tables are not a secondary output. They are required inputs for:
- Field and area reservoir simulations
- Integrated asset models
- Production forecasts used for planning and decision-making
When multiple wells share infrastructure, the accuracy of VFP tables for the overall production system becomes just as important, if not more so, than accuracy at the single-well level.
The importance of the unstable flow region
One aspect of VFP behavior that deserves special attention is the unstable flow region at low rates.
This is the regime where liquid loading, intermittent flow, and changing flow patterns dominate the pressure response. On a VFP curve, this often shows up as a non-monotonic relationship between rate and bottomhole pressure.
This region plays a role in:
- Predicting when a well starts to load up
- Assessing when artificial lift becomes necessary
- Understanding minimum sustainable rates
How this region is represented in VFP tables has a direct impact on well operability in coupled models. It is also crucial to plan artificial lift for well kick-starting when liquid loading may become an issue.
In the North Sea this phenomenon typically plays a part for depleted fields, or fields with high watercut. Some examples: Naturally Huff-n-Puff producers in low permeable depleted reservoirs, depleted rich gas-condensate fields, and fields with high watercut. Special attention should be put here because many wells spend meaningful time in this part of the operating envelope.
Making VFP tables explicit and consistent
A key principle is that VFP tables should be generated with clear and explicit assumptions.
That means being deliberate about:
- Well configuration
- Flow correlations
- Artificial lift settings
- Ranges for WHP, liquid rate, GOR, and WOR
- Whether the instability region is included or excluded
The goal is not complexity for its own sake, but transparency. When VFP tables are explicit, it becomes much easier to understand why a coupled model behaves the way it does.