The room air temperature seems quite high when ACH is low. For example, for 100 cfm air flows through room with volume 2470 cu ft. When the surrounding temperature is 81F, by doing the energy balance i.e. heat load(at 81F)=heat absorbed by air(mass flow rate*specific heat*temp rise) we get very high inside temperature above 100F. Does this mean that mean high flow rate is needed for maintaining comfort by ventilation only even at 81F.....need some help here Is it practical to create sensation of 77F inside room when outside temperature is 81F just by passive ventilation??

Is it practical to create sensation of 77F inside room when outside temperature is 81F just by passive ventilation??

Maybe on a windy, very low humidity day. But generally no.

I think it is an interesting question as to exactly when it is beneficial to open windows. Say you have everything sealed up and are relying on thermal mass or A/C or dehumidification for cooling. Under exactly what conditions is it better to open the windows?

Thank you!! If I only consider cooling at night only for comfortable sleep, with windows closed and wind flowing through the vents, but the temperature rise is too high and the hot air stays in room for too long. If i chose stack ventilation, the height and diameter of stack increase exceeds the acceptable limits. So a fan can be added to increase the flow. However even in 400 cfm that gives nearly 8.5 ACH the temperature in the room is still high...