Air Receiver Volume:

where

t = time for the receiver to charge or discharge, min

Example:

Inputs:t = 5 min

350 cfm

250 cfm

14.7 psia

100 psig

60 psig

Calculation:

V = 183.75 1374.546 U.S. gallons

5.20

Prepared by: Ankur SrivastavaChemical Engineere-mail: ankur_2061@hotmail.com

V = t*(qout -qin)*Pa / (P1-P2)

V = Volume of the receiver tank, ft3

qout = air flow out of the recieiver (surge flow to consumer), cfm

qin = air flow into the receiver from compressor, cfm

Pa = Atmospheric Pressure (14.7 psia)

P1 = Upper or Maximum operating pressure, psia or psig (P1 and P2 should both be either in absolute or gauge units)

P2 = Lower or Minimum operating pressure, psia or psig (P1 and P2 should both be either in absolute or gauge units)

The output from a compressor is 250 cfm. There is a surge flow requirement of 350 cfm for a period of 5 minutes. The upper or maximum operating pressure is 100 psig and the lower or minimum operating pressure is 60 psig. What size of receiver is required to cater to the surge volume rate demand and surge time?

qout =

qin =

Pa =

P1 =

P2 =

ft3

m3

Disclaimer: The information and methods included within this spreadsheet are presented for air receiver sizing. It is intended to be used by technically skilled persons at their own discretion. I do not warrant the suitability or accuracy of these methods.

Compressed Air Receiver Volume:

Rule of Thumb for compressed air receiver sizing is 1 U.S. gallon capacity for every ACFM compressor flow

Example Problem:

Calculations:Volume at actual pressure and temperature is calculated by ideal gas law

Now by ideal gas law

Where the subscript 1 describes the standard conditions of pressure and temperature and subscript 2 describes the actual conditions of temperature and pressure Standard Pressure = 14.7 psiaStandard Temperature = 68 °FFlow Rate @std pr.& temp. = 300 scfmDischarge Pressure = 100 psigDischarge Temperature = 40 °C

14.7 psia

300 scfm

528 °R (68+460)

114.7 psia (100+14.7)

564 °R (1.8*(40+273.15))

41.05 acfm

Calculate Compressed Air Receiver VolumeReceiver Vol. per ACFM = 1 gallonReceiver Vol. for example = 41.05 gallon

5.49

0.16

Prepared by: Ankur SrivastavaChemical Engineere-mail: ankur_2061@hotmail.com

If the compressor volume flow is described at standard conditions (14.7 psia, 68°F), it will be needed to convert it to actual volume flow (e.g. compressor discharge) at actual conditions of pressure and temperature. As an example this means converting volume flow in SCFM (Sm3/h) to ACFM (m3/h)

The volume flow of a compressor is described in standard conditions as 300 scfm. The compressor discharge conditions are given as follows: a) Discharge pressure: 100 psig, b) discharge temperature: 40°C. Calculate the compressed air receiver volume for the given discharge conditions.

P1*V1 / T1 = P2*V2 / T2

Calculate value of V2

P1 =

V1 =

T1 =

P2 =

T2 =

V2 = (T2/T1)*(P1/P2)*V1

ft3

m3

Disclaimer: The information and methods included within this spreadsheet are presented for air receiver sizing. It is intended to be used by technically skilled persons at their own discretion. I do not warrant the suitability or accuracy of these methods.

Rule of Thumb for compressed air receiver sizing is 1 U.S. gallon capacity for every ACFM compressor flow

Where the subscript 1 describes the standard conditions of pressure and temperature and subscript 2 describes the actual conditions of temperature and pressure

If the compressor volume flow is described at standard conditions (14.7 psia, 68°F), it will be needed to convert it to actual volume flow (e.g. compressor discharge) at actual conditions of pressure and temperature. As an example this means converting volume flow in SCFM (Sm3/h) to ACFM (m3/h)

The volume flow of a compressor is described in standard conditions as 300 scfm. The compressor discharge conditions are given as follows: a) Discharge pressure: 100 psig, b) discharge temperature: 40°C. Calculate the compressed air

: The information and methods included within this spreadsheet are presented for air receiver sizing. It is intended to be used by technically skilled persons at their own discretion. I do not warrant the suitability or