Rotameters are the most widely used type of variable-area (VA) flowmeter. In these devices, the falling and rising action of a float in a tapered tube provides a measure of flow rate .
What are the advantages of using a variable area flowmeter?
Advantages of Variable Area Flow Meters (Rotameters)
- All ABB rotameters are low cost compared to other flow measurement devices.
- In addition they have very low installation costs; no upstream/downstream straight piping requirements.
- Plus their reliability combines for an extremely low cost of ownership.
Which of the following is the main drawback of variable head flowmeter?
Limitations: Square root relationship between flow rate and differential pressure, therefore smaller span. Affected by pressure and density changes.
Which is known as variable head meter?
A variable area meter measures the flow of fluid by permitting the cross-sectional area of the meter to change in accordance to the flow of the liquid. … A variable head meter has a constant area of orifice or constriction. The pressure drop is dependent on the flow rate.
What is the type of variable area?
Area meters are of two general types : Rotameters and. Piston type meter.
Which is the variable area meters?
What is a Variable Area Flow meter? The variable area flow meter is an industrial flow meter used to measure the flowrate of liquids and gases. The variable area meter consists of a tube and float. The float response to flowrate changes is linear, and a 10-to-1 flow range or turndown is standard.
Which one is correct statement for rotameter variable area meter?
Rotameters or variable area flow meters, operate on the principle that the variation in area, of flow stream required to produce a constant pressure differential, is proportional to flow rate.
What are the types of flow meters?
Types of Flow Meters
- Coriolis Meters.
- DP Meters.
- Magnetic Meters.
- Multiphase Meters.
- Turbine Meters.
- Ultrasonic Meters.
- Vortex Meters.
Is Venturimeter variable area flow meter?
The orificemeter, Venturimeter and flow nozzle work on the principle of constant area variable pressure drop. Here the area of obstruction is constant, and the pressure drop changes with flow rate. On the other hand Rotameter works as a constant pressure drop variable area meter.
Which is cheapest device for measurement of flow?
Explanation: Flow nozzle is the most economical device for the measurement of flow. Dall flow tube, Venturi and Pitot static tube are comparatively expensive.
What is variable flowmeter?
The variable area flow meter is an industrial flow meter used to measure the flowrate of liquids and gases. The variable area meter consists of a tube and float. … The variable area flow meter is popular because it has a linear scale, a relatively long measurement range, and low pressure drop.
Why is it called a rotameter?
The variable-area flowmeter is called a rotameter because the float spins, or rotates, as the flow passes it. The spinning float is a clear indication that fluid is flowing. Variable-area technology was invented in Germany more than 100 years ago.
What is measured using a Venturi meter?
A Venturi Meter is mainly used to estimate the rate of flow of liquid through a pipe by decreasing the cross-sectional area and creating a gradient of pressure. Hence, a Venturi meter is used to measure the rate of flow of fluid flowing through a pipe.
Which among the following is a constant head variable area flow meters?
Rotameter: Rotameter works as a constant pressure drop variable area meter.
What is the difference between flow meter and rotameter?
A rotameter (variable area meter) is a flow meter that measures volumetric flow of liquids and gases. There is no difference between a rotameter and flow meter, and these terms are used interchangeably. … The flow rate is then read from either a scale next to the tube or a scale on the tube.
What are 3 types of variables?
There are three main variables: independent variable, dependent variable and controlled variables. Example: a car going down different surfaces.
What are the 5 types of variables?
There are different types of variables and having their influence differently in a study viz. Independent & dependent variables, Active and attribute variables, Continuous, discrete and categorical variable, Extraneous variables and Demographic variables.
What is variable and its types?
Variables represents the measurable traits that can change over the course of a scientific experiment. In all there are six basic variable types: dependent, independent, intervening, moderator, controlled and extraneous variables.
What is variable head?
Variable head permeability test is one of several techniques by which the permeability of soil is determined. It is used to evaluate the permeability of fairly less previous soil. Permeability is the measure of the ability of soil to allow water to flow its pores or voids.
Why are flow meters called variable head meters?
The basic principle on which variable-head meters are based is that when a fluid stream is restricted, its pressure decreases by an amount that is dependent on the rate of flow through the restriction. Therefore, the pressure difference between points before and after the restriction can be used to indicate flow rate.
What is head type flow meter?
Differential pressure flowmeters are also known as Head type flowmeters. They are the most prevalent type of flowmeters in use today. … The flow rate is calculated by measuring the pressure differential and extracting its square root.