What are the different factors which influence the choice of method used for the measurement of flow?

Conductivity, temperature, pressure, and viscosity can affect certain types of flow meters. How clean or dirty the water is may also impact the type and style of meter. So, the next step in choosing a flow meter is to thoroughly understand the characteristics of the flow to be measured.

Why rotameter tube is tapered?

Why is tapered glass used in a rotameter? – Quora. A tapered glass tube helps to create a variable ring orifice. In other words, it helps to vary the area around the float or bob which is in the tapered glass tube so that the drag force can be measured. Here, the buoyancy and the weight of the float is constant.

What is rotameter used to measure?

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.

What is flow Transmitter?

Flow transmitters provide electrical outputs that are proportional to flow inputs. They use flow meters to measure the flow of liquids and gases. Flow transmitters use three basic types of meters: mass, volumetric, and velocity.

Which flowmeter is most accurate?

Coriolis mass flow meters produce the most accurate for most liquids but are expensive. They have the advantage of not needing any knowledge about the fluid being carried. Thermal mass flow meters are a less accurate but still direct measurement method. They do require knowledge of the fluid’s specific heat capacity.

Do Rotameters need to be calibrated?

A rotameter is typically designed for one specific gas density and flow range, so without the rotameter being calibrated to those conditions, accuracy will suffer. Calibrating a rotameter will identify the reference conditions in which the rotameter will be used, thus offering the most precise measurements.

How does a hot wire anemometer measure flow?

Hot Wire Anemometer works When an electrically heated wire is placed in a flowing gas stream, heat is transferred from the wire to the gas and hence the temperature of the wire reduces, and due to this, the resistance of the wire also changes. This change in resistance of the wire becomes a measure of flow rate.

What is A rotameter and how does it work?

A rotameter measures the flow of liquids, gases and steam by using a float inside a conical tube. The rotameter principle is one of the oldest and most mature principles in flow measurement.

Can A rotameter be sized for other fluids?

Sizing a rotameter for use with other fluids requires conversion into one of those standard formats; for liquids, the water equivalent in gpm; for gases, the air flow equivalent in standard cubic feet per minute (scfm).

How does the shape of a float affect A rotameter?

It has been found that the shape of the float determines to a large extent the way in which a rotameter will be affected by changes in the viscosity of the fluid measured. It has been found that floats having sharp edges are relatively insensitive to changes in viscosity in a range of considerable viscosity.

How does rotrotameter/variable-area flow meter work?

Rotameter/Variable-Area flow meters can be calibrated to measure nearly any gas or liquid, because their principles of operation are simple and well understood. The flow indication is obtained from a balance of the fluid forces underneath the float with gravity.