SAL COLLEGE OF ENGINEERING Department of Chemical Engineering ALA Subject : Fluid Flow Operation( ) TOPIC: Manometer Student : Koladiya Sandip Name: Faculty: Dr. Bhavna Soni

Introduction Pressure mesurment is one of the most important mesurment in continuous process industries. Manometer mesure the unknown pressure by balancing against the gravitational force of liquid heads.

Manometer Menometry refers to the mesurment of pressure by comparision to the hydralic pressure produced by a column of liquid. With the help of menometer, we can mesure comparatively high pressure and negative pressure also.

Types of Manometer U – tube Manometer. Inclined tube manometer. Well type manometer. Micromenometer.

U – tube manometer 1.It is simplest manometer. 2. Used in mesurment of high liquid or gas pressure. D a 3. Both legs have same area. Z m 4. Manometric fluid of known specific gravity is used. R m like Hg (high density), CCl3 (medium density), H2O (low density) etc.. D b 5.Mercury is genreally used as fluid because of density is high.

P 1 + G { (Z m +R m ).D b – R m.D a – Z m.D b } – P 2 =0 P 1 –P 2 = G.R m (D a -D b ) Where, D a = Density of liquid A. D b = Density of liquid B. R m = Mercury level different. Z m = different of density of liquid.

Properties and charectrastics of manometer Indicating fluids Liquid manometer measure differential pressure by balancing the weight of a liquid between two pressures. Light liquid such as water can measure small pressure differences; mercury are used for large pressure differences. For an indicating fluid 3 times heavier than water,the pressure measurement range is 3 times grater, but the resolution is reduced.

So that any type of manometer are used but only for heavy liquid are used like mercury, etc never than the other fluid are used. Because of Indicating fluids can be colored water, oil, benzenes, bromides, and pure mercury. when selecting an indicating fluid, check the specification of specific gravity, operating temperature range, vapour pressure and flash point, corrosive properties,solubility,and toxicity are also considerations.

Different types of pressure There are different type of pressure are used in manometer like gauge pressure, absolute pressure, atmospheric pressure etc.. Absolute pressure = Atmospheric pressure + Gauge pressure Gauge pressure : A measurement referenced to the atmospheric pressure. Its varies from the measurement of barometric reading and manometer reading.

Atmospheric pressure : The pressure of the atmosphere of the unit surface is also called barometric pressure. Absolute pressure : The complete absence of any gas ; a perfect vacuum.

Inclined tube manometer It is slant manometer. The angle of mesuring leg is about 10 degree. Inclined is done improve the sensitivity. This manometer is used to mesure Inclined tube manometer very small pressure difference. Where, Rm = mercury level different Eqation of inclined manometer. Da = density of liquid A. P 1 – P 2 = G.R m (D a – D b ).sin α Db = density of liquid B. α = Given angle or 10 degree.

A variation of the well type manometer is this inclined tube manometer. A vertical rise is stretched over serval inches of scale length. This scale is used in 12 inches. The inclined tube manometer has battery sensitivity and resolution for low pressure.

Example : An U-tube manometer is liquid A is mercury (13,590 kg/m3) and fluid B, flowing through the orifice and filling the manometer leads, is brine density (1,260kg/m3). And the level of Hg is 0.9m below the orifice taps. And the gauge pressure at the upstream tap is 0.14 bar, the pressure downstrem is 250 mmHg below atmosphiric.what is the reading of the manometer in mm? and also find inclined manometer installed where α = 300 ° Given Data: D a = 13,590 kg/m3 D b = 1,260 kg/m3 P a = 0.14 bar g = m/s2 Z b = - 250/1000 mHg ( -ve is indicated downstrem tap pressure) α = 300 ° R = ?

The gauge pressure at the upstreme tap is, P a = 0.14 × (10)5 = 14,000 pa Now we know that Heat transfer equillibrium, P b = Z b.g.D a = - 250/1000 × × 13,590 = - 33,318 pa eq n of manometer, P a + P b = R m × g × (D a – D b ) 14, ,318 = R m × × ( 13,590 – 1,260 ) R m = 391 mm

We know that equation of inclined manometer, P a –P b = g.R m.sin α ( D a - D b ) 14, ,318 = R m × ×sin 300 ° (13,590 – 1260) R m = 0.41 m R m = 410 mm

Advantages and Disadvantages of Manometer Advantages Disadvantages Simple. 1. Not portable. Accurate. 2. Need of accurate levelling. Good Repeatability. 3. Small range about 1000kN/m 2 Wide range of fluid can be used.

Thank You.