Formula for Density Calculation Steam

Please tell me the formula, since some formula is used in our plant, i want to find the authenticity of the reading,

Density = (Pressure * 19)/(1.48+0.01*Temperature-0.0452*pressure).

Pressure - MPA,

Temperature - Degress celsius.

pls check the autenticity of the formula.

All Flow Meters for Steam & Gas MUST have "Density Compensation" to safeguard against error in reading depending on difference between the specific density and the actual flow density.

Error in Orifice /Differential Pressure Device :

[√ specific volume actual/specific volume -1 ] x 100

= :[√ 4.44 cu.ft/lb/3. cu.ft/lb -1 ] x 100 = 6.8% over reading by Meter

Error in Vortex Pressure Device :

[specific volume actual/specific volume -1 ] x 100

= :[ 4.44 cu.ft/lb/3.89 cu.ft/lb ]- 1 x 100 = 14.0% over reading by Meter

Calibrated for 100 psi (specific volume 3.89 cu.ft/lb ) when

actual is 85 psi (specific volume 4.44 cu.ft/lb)

Example case, the Boiler House Boiler is at say ≤8.0 Bar = 115 psi or 3.46 cu.ft/lb specific volume. Whereas you are getting ≤5.0 Bar at your Header = 70 psi or 5.19 cu.ft/lb specific volume.

Now your meter was calibrated at obviously 8.0 bar or 115 psi while you are getting

≤ 5.0 bar or 70 psi. Therefore based on above the Error in Reading without density compensation on an Orifice flow Meter will be :

Error in Orifice /Differential Pressure Device :

[√ specific volume actual/specific volume -1 ] x 100

= :[√ 5.19 cu.ft/lb/3.46 cu.ft/lb -1 ] x 100 = 22.47 % over reading by Meter

https://www.google.com.ar/search?q=formula+for+calculation+of+density+of+steam&oq=formula+for+calculation+of+density+of+steam&aqs=chrome.0.57&sugexp=chrome,mod=13&sourceid=chrome&ie=UTF-8

If you want a program, I use WASP (Water and Steam Properties) excellent results.

http://www.katmarsoftware.com/wasp.htm

You can always use pV=nRT and get fairly good results. Knowing that m=Mn where M=18.0538 g.mol-1 for water and steam, and R = 8314 J.kmol-1.K-1, we have:

p * V = (m / 18.0538 g.mol-1) (8314 J.kmol-1.K-1) T

V / m = (1 / 18.0538 g.mol-1) (8314 J.kmol-1.K-1) T/p

rho = m/V = (18.0538 kg.kgmol-1) 1/(8314 J.kmol-1.K-1) (p/T)

rho is the density

rho = ( 18.0538 kg / 8314 N.m.K-1) (p / T)

where p is expressed in Pa and T is expressed in K. The density, rho, is in kg.m-3.

I think that you live in a country that uses SI units, so I did this that way.

You could also look on page 24 of this book:

https://books.google.com/books?id=EQYa6gzXXtoC&pg=PA24&lpg=PA24&dq=647.096+1.84408259+-11.7866497&source=bl&ots=eI3iH6dHJu&sig=VSv5H_nizjgFFW0RdFdWVUUWR9E&hl=ru&sa=X&ved=0ahUKEwi4zsiPtNjOAhVJyWMKHeXuDR4Q6AEIHjAA#v=onepage&q=647.096%201.84408259%20-11.7866497&f=false

Physical Property Data Book: For Engineers and Scientists

Авторы: David C. Shallcross