# Manometer

Manometers is the devices during which an acceptable liquid is employed within the Mano-metric column to observe the difference in pressure between 2 totally different locations or one will say between a definite point and therefore the atmosphere. mostly 5 Types of manometer.

### Types of Manometer

1. U-Tube Manometer
2. Differential U-Tube Manometer
3. Inverted U-Tube Manometer
4. Small Manometer
5. Inclined Manometer

### 1. U-Tube Manometer

This manometer is extremely easy to construct.

It consists of a U – formed bent tube whose one end is hooked up to the gauge Location ‘A’ and alternative Location is receptive the atmosphere. it’s then stuffed with a Liquid.

The density of the Liquid dictates the vary of pressures that may be observed.

If one port is left open to the atmosphere and therefore the alternative port is connected to the pressure to be observe, the device acts as a gauge pressure meter.

If each ports are connected to 2 totally different unknown pressures, the instrument acts as a differential gauge.

It will observe each positive and negative pressures. It contains liquid of specific gravity larger than that of a liquid of that the pressure is to be observe.

where ‘γ’ is specific weight of the Liquid, ‘P’ is Pressure at A (which u r going to calculate).

Hence; Pressure at A is P = γ2h2 – γ1h1

### 2. Differential U-Tube Manometer

Differential U-tube manometer is extremely similar to the U-tube manometer as we tend to mentioned on top of. Here one open Location (which was thought-about as atmospheric Location in U-Tube manometer ) is connected to a different pressure Location i.e

This manometer is largely used to observe the differences between to totally different points otherwise you will say we tend to calculate the difference.

Pressure distinction between A and B is given by equation

### 3. Inverted U-Tube Manometer

Inverted U-Tube manometer is employed for the measuring of tiny pressure differences in liquids.

It consists of associate inverted U – Tube containing a light-weight liquid. this is often used to observe the differences of low pressures between 2 points wherever higher accuracy is needed.

It typically consists of associate air cock at prime of Mano-metric Liquid kind.

Note : Inverted U-tube differential manometer are used for mensuration the vacuum pressure. Inverted U-tube differential manometer can have one inverted U-tube contained with light-weight liquid.

Let us think about that inverted U tube differential manometer is connected with 2 points in 2 pipes as displayed here in following figure.

These 2 pipes are full of totally different relative density liquid. As displayed here in figure, purpose A and purpose B are at totally different level.

Pressure distinction are often calculated from the below mentioned equation

PA – ρ1gH1 – ρmg(H2– H1) = Pb – ρ2gH2

PA – ρ1g H1 = Pb – ρ2g H2 – ρL g H

After rearranging

PA – Pb = ρ1g H1 – ρ2g H2 + ρmg(H2– H1)

Where ρm = density of Mano-metric Liquid

ρ2 , ρ1 = density of 2 totally different Liquid

### 4. Small Manometer

The micro-manometer could be a special kind of of liquid column manometers that that is predicated on the principle of inclined tube manometer.

It used for the measuring of very tiny variations of pressure or terribly low pressure variations. One will say micro-manometer is that the changed kind of an easy manometer whose one limb is formed of larger cross sectional space.

It observe so little pressure variations with high exactness.

Let ‘a’ = area of the tube,

A = area of the reservoir,

h3 = Falling liquid level reservoir,

h2 = Rise of the liquid within the tube,

By conversation of mass we tend to get A*h3 = a*h2

Equating pressure heads at datum we tend to get

p1=(pm-p1)*gh3+gh2-p1*gh1

### 5. Inclined Manometer

Inclined manometer is employed for the measuring of tiny pressures and is Observe a lot of accurately than the vertical tube kind manometer.

Because of inclination the gap affected by the Liquid in manometer is a lot of. associate inclined manometer could be a slightly curved tube with a liquid within, usually a kind of oil mixture. on the tube’s middle portion are graduations.

The graduations ar normally hundredths of an in., looking on the manometer’s manufacturer.

Benefits

The manometer’s inclined angle provides several benefits. a little or low quantity of pressure against the inclined manometer can manufacture an oversize liquid movement relative to the tube’s graduations.

As a result, the graduation scale are often so precise–down to a hundredth of an MM accuracy.