Pitot Tube Liquid Flow Meters

Description

Pitot Tube Liquid Flow Meters are devices used to measure the flow rate of liquids by assessing the pressure difference created by the fluid flow. They consist of pairs of hollow tubes, where one tube measures the impact pressure and the other measures the potential pressure.

Working Principle

Pitot Tube Liquid Flow Meters operate by converting the kinetic energy of the fluid flow into potential energy, or pressure. This is achieved by placing the open end of a tube facing the direction of the flow, which measures the dynamic pressure. A second tube, oriented at a right angle to the first, measures the static pressure. The difference between these two pressures is used to calculate the flow velocity. This method is particularly useful because it allows for easy insertion into existing piping systems, minimizing installation costs .

Applications

Pitot tubes are commonly used in large pipe diameters, typically greater than DN 100, where fluid velocity needs to be preserved . They are also employed in HVAC systems to measure air flow .

Advantages over other Liquid Flow Meters

Pitot tubes are relatively inexpensive compared to other flow meters and incur very small pressure losses, making them suitable for applications where maintaining fluid velocity is crucial . They are also easy to install, as they can be inserted into existing piping systems without significant modifications .

Limitations

Pitot tubes require very clean fluids, as solids can easily plug the tubes, leading to inaccurate measurements . Additionally, they need specific inlet and outlet sections and a minimum Reynolds number to function correctly .

Considerations

When considering Pitot Tube Liquid Flow Meters, it is important to account for the initial low cost and minimal installation expenses due to their simple design and ease of insertion into existing systems . However, maintenance costs can increase if the fluid contains particulates that may clog the tubes. Durability and accuracy can be affected by improper installation and maintenance, as highlighted by historical incidents in other applications .

5 Results
Pressure Based Flow Meter -- Accelabar®
from Armstrong International

Accelabar is a new and unique flow meter that combines two differential pressure technologies to produce high accuracy and low velocity flow rates at turndowns tested up to 65:1 with no straight run requirements. The Accelabar consists of a unique toroidal nozzle design and a Verabar averaging... [See More]

  • Meter Technology: Pitot Tubes; Venturi Tube
  • Operating Pressure: 50
  • Process Media Type: Liquid; Gas; Steam
  • Media Temperature: 70
Economical Flowmeter -- FL30000
from OMEGA Engineering, Inc.

FL-30000 Series flow meters use a pitot tube pickup and a hard-edged float design to provide a convenient and economical means of measuring water flow in a closed pipe system. A one-piece, impact-resistant machined acrylic body offers the strength and long service required in most commercial and... [See More]

  • Meter Technology: Pitot Tubes
  • Operating Pressure: 150
  • Process Media Type: Liquid
  • Media Temperature: 190
Model 300 Series -- 300-AA
from Mid-West Instrument

The Model 300 Series Inline Delta Tube Flow Element may be used for the measurement of flow in pipe lines from 1/2 ” NPS through 3 ” NPS. The Model 300 Series utilizes two averaging flow elements of equal area to sense stagnation (RAM) and static differential pressure providing minimum... [See More]

  • Meter Technology: Pitot Tubes
  • Operating Pressure: 4640
  • Process Media Type: Liquid; Gas; Steam
  • Meter Type: Velocity Flow Meter
Pressure Based Flow Meter -- Verabar®
from Armstrong International

Verabar provides the most accurate, reliable technology for measuring gas, liquid and steam as well as the lowest operating and installation costs. The Verabar senses the natural averaged pressures created by the velocity of the fluid. When the fluid impacts the sensor, it creates a high-pressure... [See More]

  • Meter Technology: Pitot Tubes
  • Meter Type: Velocity Flow Meter
  • Process Media Type: Liquid; Gas; Steam
  • Mounting: Insertion
Model 301 Series -- 301-AG
from Mid-West Instrument

316 stainless steel welded flow element, anti-blowout protection [See More]

  • Meter Technology: Pitot Tubes
  • Operating Pressure: 2980
  • Process Media Type: Liquid; Gas; Steam
  • Meter Type: Velocity Flow Meter