# Full-Section Matrix Flowmeters

> Patented multi-point velocity-array measurement. A patented multi-point differential-pressure array engineered for large circular pipes, rectangular ducts and gas-flow profiles that a single-point or single-bar probe may not represent.

## Overview

The Shizhong Full-Section Matrix Flowmeter combines a multi-point sensing array with an integrated flow-conditioning structure to sample a broader area of the measuring section. Each system is designed around the actual duct geometry, upstream disturbance, gas properties, maintenance conditions and acceptance method. Project performance is established through an approved system coefficient, representative calibration or site correlation—not a universal coefficient transferred between installations.

## Measurement architecture

Shizhong offers three signal architectures because a multi-point array is not automatically an arithmetic area average:

1. **Pneumatic averaging:** total- and negative-pressure circuits are manifolded to one DP transmitter. The complete array requires a system coefficient for the approved installation basis.
2. **Zoned averaging:** sections of the duct are measured separately, improving diagnostics for asymmetric profiles.
3. **Multi-channel velocity integration:** local velocities are calculated from individual differential pressures and integrated using defined area weights.

For a multi-channel arrangement:

`Q = Σ(A_i × C_i × sqrt(2 × Δp_i / ρ))`

For a pneumatic averaging arrangement:

`Q = K_sys × A × sqrt(2 × Δp_m / ρ)`

The supplied calculation package defines the coefficient, density basis, units and accepted operating envelope. Coefficients are not transferred between unrelated arrays or duct layouts.

## Application engineering rules

- Provide the duct size, full upstream/downstream layout and all disturbances.
- Define minimum, normal and maximum flow, pressure, temperature, composition, moisture and dust loading.
- State whether the output is actual volume, standard volume or mass flow.
- Confirm purge, drainage, heat tracing, inspection access and removal clearance for difficult gas service.
- Select the reference method, site correlation, calibration and CEMS acceptance requirements before fabrication.

## Standards boundary

ISO 3966:2025 provides velocity-area principles for Pitot-static measurements in regular, steady, full-conduit flow. ISO 16911-1/-2 supports stationary-source reference and automated measurement practice. These references do not assign a universal coefficient or guaranteed straight run to a proprietary matrix array. ISO 5167 does not cover matrix probes.

## Selection caution

Strong swirl, reverse flow, wet deposits, sticky or crystallizing contaminants and extremely low differential pressure require a feasibility review. More sensing points do not guarantee lower uncertainty; placement, weighting, hydraulic balance, calibration, density compensation and long-term maintenance determine system performance.


## Technical specifications

| Parameter | Specification |
|---|---|
| Size range | Round 25–6000 mm; rectangular 50 × 50 to 4000 × 4000 mm (source-family engineering range) |
| Measurement geometry | Not applicable — velocity-array system |
| Reynolds-number range | Application-specific; verify local probe Reynolds number and differential-pressure signal margin |
| Pressure taps | Multi-point total-pressure array with a matched negative-pressure circuit; pneumatic, zoned or multi-channel output |
| Accuracy | Project-specific; historical brochure classes ±0.5%, ±1.0% and ±1.5% require an approved calibration or site-correlation basis |
| Turndown ratio | Project-specific; set by minimum usable DP, density variation, transmitter span and the correlation model |
| Permanent pressure loss | Low relative to full-bore restriction devices; calculate for the supplied array and flow conditioner |
| Discharge coefficient | System coefficient Ksys established for the supplied array and acceptance basis |
| Temperature range | Application-specific; source family historically listed -100°C to +850°C, subject to material and mechanical review |
| Pressure rating | Application-specific; pressure boundary, supports, connections and design code must be reviewed |
| Materials | 304 or 316L stainless steel; duplex and nickel-alloy options after corrosion and mechanical review |
| Straight-run requirement | Layout-specific; review upstream disturbances, flow angle, profile survey and the agreed acceptance method |

## Standards

CN212082473U patented architecture; ISO 3966:2025 velocity-area principles; ISO 16911-1/-2 and applicable CEMS requirements by project

## Applications

- Boiler primary-air, secondary-air, forced-draft and induced-draft systems
- Flue-gas ducts for power, steel, cement and chemical plants
- Large circular pipes and rectangular ventilation or process-gas ducts
- Continuous gas-flow measurement with site traverse or project calibration

## Features

- CN212082473U patented full-section sensing architecture
- Broader two-dimensional section coverage than a single-point or single-bar probe
- Circular and rectangular arrays engineered around the actual velocity profile
- Low permanent pressure loss compared with full-bore restriction devices
- Calibration-, site-correlation- and CEMS acceptance-ready documentation

## Contact and source links

- Product page: https://www.shizhongflow.com/products/matrix-flow-meters
- Product catalog API: https://www.shizhongflow.com/api/products
- Selection API: https://www.shizhongflow.com/api/select
- Request an engineering review: https://www.shizhongflow.com/contact
- Email: info@shizhongflow.com
- Phone/WhatsApp: +86-188-0531-6689

Final sizing, materials, pressure-boundary design, calibration and compliance are confirmed against the complete process data sheet and project requirements.