A nutating disk flow meter, also known as a wobble plate meter, is a type of positive displacement flow meter used to measure the flow rate of liquids in various industrial applications. It operates based on the principle of positive displacement, where fluid flow causes a mechanical displacement of a measuring element. Here are the basics of nutating disk flow meters:

1. Principle of Operation:

   • The nutating disk flow meter consists of a disk or rotor mounted on a central ball or spherical bearing. The disk is typically eccentrically mounted within a circular chamber.
   • As the fluid flows through the chamber, the disk nutates or wobbles on its central bearing due to the pressure difference between the inlet and outlet of the meter.
   • The motion of the disk creates a series of volumetric chambers between the disk and the chamber wall. These chambers sequentially fill and empty with fluid as the disk rotates, displacing a known volume of fluid with each revolution.

2. Measurement of Displacement:

   • The displacement of the nutating disk is converted into mechanical motion, which is then transmitted to a mechanical counter or electronic sensor system.
   • Mechanical systems typically use gears and linkages to transmit the motion of the disk to a mechanical counter or register, which records the total volume of fluid passing through the meter.
   • Electronic systems may use magnetic pickups, optical sensors, or other types of transducers to detect the motion of the disk and convert it into an electronic signal for digital display or data logging.

3. Accuracy and Rangeability:

   • Nutating disk flow meters offer high accuracy and repeatability over a wide range of flow rates. They are capable of measuring low to moderate flow rates with high precision.
   • The flow range of nutating disk meters can be adjusted by selecting an appropriate meter size and disk geometry to match the flow characteristics of the fluid and the application requirements.

4. Fluid Compatibility:

   • Nutating disk flow meters are suitable for measuring a wide range of clean or slightly viscous liquids, including water, fuels, oils, chemicals, and solvents.
   • They are not suitable for highly viscous fluids or fluids containing abrasive particles, as these may cause excessive wear or damage to the meter components.

5. Installation and Maintenance:

   • Nutating disk flow meters are typically installed in-line with the flow piping using standard threaded or flanged connections.
   • Proper installation orientation is important to ensure accurate measurement and minimize pressure drop across the meter.
   • Regular calibration and maintenance are essential to ensure accurate and reliable performance. This may involve periodic inspection, cleaning, lubrication, and calibration of the meter components.

Nutating disk flow meters offer several advantages, including high accuracy, reliability, simplicity, and suitability for a wide range of fluid types and flow rates. However, they may have limitations in terms of fluid viscosity, pressure drop, and compatibility with certain fluid characteristics. Careful consideration of the application requirements and proper installation and maintenance are necessary to ensure accurate and reliable performance of nutating disk flow meters.