Advanced Virtual Flow Meter
Accurate flow estimates at valve locations — no physical flow meter needed.
The Problem
Flow meters are expensive, difficult to install at certain process locations (in-line at valves, heat exchangers, or cryogenic circuits), and prone to fouling or calibration drift. Many processes operate without flow measurement where it would most improve control quality.
The Solution
The Advanced Virtual Flow Meter (AVFM) calculates volumetric or mass flow from measurements already available in virtually every process: valve position, upstream and downstream pressure, and fluid temperature. The reverse valve-sizing equation translates these into a flow estimate — no additional hardware required.
How It Works
- Valve position sensor → Cv characteristic curve lookup
- Pressure differential (upstream − downstream) → volumetric flow from valve equation
- Fluid temperature → density and viscosity correction
- Nonlinear estimation → compensates for systemic effects and model uncertainty
- Online dynamics model → tracks transient flow changes during valve opening/closing
Accuracy
Accuracy is limited by the quality of available measurements and knowledge of the installed valve characteristic (Cv curve). A valve calibration procedure is recommended for best results. The nonlinear estimation layer further improves accuracy by accounting for pressure drop across pipe fittings, temperature-dependent fluid properties, and off-design operation.
Typical Applications
- Flow monitoring at control valve positions without physical meters
- Heat load estimation in process heat exchangers
- Soft redundancy for existing flow meters (fault detection)
- Flow inference in cryogenic and high-pressure circuits
- Input to advanced process control and economic MPC layers
Interested in the AVFM for Your Process?
The AVFM is developed and deployed as a project-specific software module. A 30-minute feasibility call is the fastest way to assess whether your valve and sensor configuration supports a virtual flow meter.