Symbol TermVelocity head

V Gas Velocity in ductg Gravitational Acceleration

Q Volume of gasNormal Volume of gas

Qg Normal mass of gasD Duct DiameterA Cross Sectional Area

Velocity Pressureρ Actual Air Density at different temp. and pressure

Air Density at NTPt Gas TemperaturePa Barometric PressureH Altitude of place in metres

Suction Pressure

Friction Loss in Straight DuctV Velocity in ductsf coefficient of friction for steelL Length of ducts including developed bendsd diameter of ductv specific volume of air, corrected for altitude and tempT Absolute temp of air in Kelvin

Friction loss in straight round ducts

Hydraulic Diameterp wetted perimeter of the duct

Friction Loss in BendsV Velocity in ducts

Coefficient of friction for bends (from figure)Friction loss in pipe bends

Lift LossL Vertical Lift

Weight of material being liftedWeight of air/gas lifting the material

K Constant = density of water/density of air (Operating)Density of water = 1

Cyan cells are input cellsYellow cells are output cells

Vh

Qn

VP

ρn

PS

Floss

Dh

K1

Floss

Wm

Wa

Density of air at NTP = 1.29 kg/m3K at NTP = 1/1.29 = 0.775

RLift Loss

Acceleration Lossmass of materialmass of air

M m1 + m2V Final velocity af air and materialWm weight of materialWa weight of airR

Acceleration Loss

Lloss

m1

m2

Aloss

Formula Value UnitV²/2g 8.384575 m

12.81943 m/sec 9.868363 m/sec 12.004349.8 m/sec²

146.9405 m³/sec 528985.8 m³/h 22806480.15833 Nm³/sec 288570 Nm³/h 124412.47584221103.4043 kg/sec 372255.3 kg/h 160492.09383646

3.82 m 2.508244 mπ D²/4 11.46233 m²

5.900353 mmwg 5.2 mmwg0.703715 kg/m³

1.29 kg/m³190 deg C

9561.72 mmwg 0.925179650 m250 mmwg

12.81943 m/sec0.018

16 m3.82 m

1.42103 m3/kg463 kelvin

13.866 x V² x L x f / (d x v x T) 0.261116 mmwg 2513.318037 181.25761120949(f L V²/2gd)xρ 0.444843 mmwg 0.6321355127

0.632136 mmwg 4.1884816754 8.38457520295564A/p 3.82πD 12.00244

12.81943 m/sec1.08

6.372381 mmwg

9.055341

10 m2 kg2

1

Vh x ρρn x 273/(273+t) x Pa/10335

10335 x (1-0.0000226 x H)^5.255

f(L/Dh) (V²/2g)

(K1 x V²/2 x g) x ρ

1

1R x L / K 10 mmwg

Lift Loss When material is lifted from one level 18

Frcition Loss Due to flow of gases (also dust laden)#DIV/0!#DIV/0! mmwg

(Wm/Wa)

Acceleration Loss

When material is introduced in a ducting and attains velocity of carrying gases

m1 x gm2 x g(Wm/Wa)R x V²/2g

m/sec

m3/h 137.5977 m³/secNm³/hkg/h

Losses in ducts

When material is lifted from one level

Due to flow of gases (also dust laden)

When material is introduced in a ducting and attains velocity of carrying gases