Hi all,

I am modeling a building of 40000 sqft area (Manufacturing building) with DX
cooling . As a EEM using Indirect/Direct Evaporative cooling .

Simulation results shows that Supply air flow -37000 cfm (DX cooling) and
21500 cfm (Evaporative cooling) at indoor design temperature of 82.5 F

Generally as per thumb rule Evaporative cooling takes almost 2 to 3 times
more supply flow than DX cooling . In my modeling it shows more than 6 times
supply flow for EVP cooling( Is this correct estimation or Anybody please
help me as per ASHRAE Fundamentals under cooled hours for these two systems
same or different for comparison of supply flow)

1)Unmet Cooling hours For DX cooling is -0.4%-37000 cfm

EVP. Cooling - 0.4%-
215000 cfm
And

2) Unmet Cooling hours For DX cooling is -0.4%-37000 cfm

EVP. Cooling - 4%-
100000cfm this relation gives the better comparison.

Please help me which comparison is correct one 1st or 2nd .

Thank you in advance

Uday...