Parshall Flume

A Parshall Flume is an open-channel flow measurement structure designed to provide reliable and continuous flow measurement without requiring the installation of moving mechanical components within the flow path.

The flume consists of a precisely engineered converging section, throat, and diverging section. As water passes through the throat, its flow conditions change in a predictable manner. The resulting upstream water level can be measured and correlated with the flow rate according to the flume’s standardized hydraulic characteristics.

This measurement principle makes Parshall Flumes particularly suitable for wastewater treatment plants and other applications where continuous flow monitoring, process control, and flow data recording are required.

Main Components

• Parshall Flume Body
• Standard-Dimension Throat
• Water Level Measurement Sensor
• Ultrasonic Level Sensor
• Sensor Mounting Bracket and Support
• Stilling Well, where required
• Level Gauge or Staff Gauge
• Control Panel and Display
• Flow Transmitter and Data Logging Equipment
• Cables and Installation Accessories
• Inlet and Outlet Connections
• Communication and Data Transmission Equipment, where required

Operating Principle

The Parshall Flume creates a controlled hydraulic condition by narrowing the flow through a precisely dimensioned throat. The water level at the designated upstream measurement point is then measured using a level sensor or ultrasonic sensor.

The measured water level is converted into a corresponding flow rate based on the standardized hydraulic relationship of the selected Parshall Flume size. When connected to a transmitter, control panel, or data acquisition system, the measured flow can be displayed, recorded, transmitted, and monitored continuously.

Key Features

• Accurate and continuous open-channel flow measurement
• Standardized hydraulic geometry for reliable flow calculation
• Suitable for water and wastewater applications
• No moving mechanical components in the flow path
• Ultrasonic or other level measurement options
• Compatible with digital displays and flow transmitters
• Optional data logging and remote data transmission
• Suitable for process monitoring and treatment plant control
• Available in different sizes and configurations
• Can be customized according to channel dimensions and project requirements

Applications

Parshall Flumes are commonly used in:

• Municipal wastewater treatment plants
• Industrial wastewater and effluent treatment plants
• Water treatment plants
• Sewage transmission and collection systems
• Open wastewater channels
• Industrial process water systems
• Flow monitoring and process control systems
• Irrigation and water management applications

Customized Flow Measurement Solutions by Mojan

Mojan supplies Parshall Flumes engineered according to the required flow measurement range, channel dimensions, hydraulic conditions, installation requirements, and instrumentation specifications.

Depending on project requirements, the system can be equipped with ultrasonic level sensors, stilling wells, staff gauges, flow transmitters, control panels, data logging systems, and communication equipment for local or remote monitoring.