Posted by John C. Ellis on March 06, 2000 at 12:13:21:
In Reply to: Re: How can I measure the heating value of a boiler?(Boiler efficiency) posted by gburns on February 12, 2000 at 14:31:26:
If you are doing this for a scholastic paper, then follow the outline for the heat loss method found in ASME 4.2. If you want a quick, reasonably precise method then do the I/O (input-output) method. This efficiency is as follows:
E= W1(H1-h1) + W2(H2-h2)/C
Where W1 = main steam flow (lb/hr)
W2 = reheat steam flow (lb/hr)
H1 = Enthalpy main steam (btu/lb)
H2 = Enthalpy reheat steam (btu/lb)
h1 = Enthalpy feed water (btu/lb)
h2 = Enthalpy steam enter reheater (btu/lb)
C = Total heat input from fuel (btu/lb)
Hope this helps.