subject: How Liquid Flow Meters Are Used In A Number Of Industries [print this page] Knowing the flow of liquids is critical within many industries. Usually, a liquid flow meter will measure the fluid's rate of flow. This is accomplished through the measurement of undulation of a flexible membrane. This is done in response to the fluids passage through the flow chamber. Throughout history, these types of meters have been used for the measurement of a liquids flow across local and long distance distribution pipes.
In addition, the liquid flow meters have been used within process transmission lines, as well as the delivery of the product for transportation within tank trucks and railroad cars. Additionally, these types of meters are sometimes used within pharmaceuticals, farming, and chemical processing, along with the production of various types of beverages. This includes soft drinks. Basically, flow meters are used within any industry where there is a need to measure liquid flow.
Often, liquid flow meters can be affected by the Reynolds Number. This is usually defined according to the liquid's inertial forces in comparison to the drag forces. The inertia forces are determined according to the specific gravity and the flow rate. As for the drag forces, they are according to the fluids viscosity and the pipes diameter.
Within most of the liquid applications, the specific gravity and pipe diameter remain constant. During times of high viscosities or extremely low velocities, the Reynolds Number is low. In addition, the liquid flows in smooth layers. Generally, the Reynolds number is below 2000 when the viscosity is high or velocity is extremely low.
In addition, the liquid flows in smooth layers. During situations such as this, the highest velocity is found at the center of the pipe. At the same time, the lowest velocities are found near the pipe wall where the liquid is reluctant to flow. This is referred to as a laminar flow.
One of the major characteristics of the laminar flow relates to its velocity profile that resembles a parabola. In most cases, many of the applications consist of a turbulent flow. Usually, the value of the Reynolds Number is above 3000. During times of low viscosities or high velocities is when a turbulent flow occurs.
With this type of flow, the average velocity remains. This is the case even as the flow breaks down into turbulent eddies, which flow through the pipe. Additionally, the fluid velocity has less significance. In addition, the velocity profile is a lot more uniform in its shape.
In general, there is a transition zone between the laminar and turbulent flows. However, the type of flow within this zone depends on the type of piping configuration in addition to other installation conditions. The basic types of liquid flow meters are:
* Differential Pressure
* Positive Displacement
* Velocity
* Mass Meters
According to experts, over seventy-five percent of the flow meters are installed within an industry and do not perform satisfactory. Ninety percent of the time, an improper selection has to do with these types of problems. Overall, when it comes to selecting a flow meter this is not something that should be done by someone who is an amateur.
