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Ventilating an unairconditioned building

Ventilating an unairconditioned building

Ventilating an unairconditioned building

(OP)
My company has a 20,000 sq ft shop in a rented building not air conditioned. Because of the fairly high daytime temperatures, 90 to100 deg f, they bought three spot coolers evaporative type. These things are now turning out to be a mixed blessing. They cool the guys in the direct stream, however they load up the rest of the shop with humid air. This of course is not going over very well with the guys away from the coolers.
  we have 3 roll up shop doors and I am thinking of installing a fan over each door about 10 fan diameters back to augment the natural  outflow at the top of the door frame. Would there be any advantage to using the "jet fan" type fan or would a standard axial flow fan be good enough? The landlord will not allow us to make any penetrations in the roof or walls to put standard ventilators in. We have three fans installed in the roof preexisting. They are noisy and inadequate.
B.E.

RE: Ventilating an unairconditioned building

(OP)
imok2 (Mechanical)
I had not seen the Ware house calculator before. that is very useful.
 I guess I did not frame my question very well. Am I better off with a smaller high velocity stream of air impinging into the door frame or with a fatter lower velocity column of air. The idea here idea to create an accelerated flow of air through the upper half of the door to encourage the natural flow and exchange of air.
B.E.

RE: Ventilating an unairconditioned building

If it were me I would go with the more natural air flow of an axial flow fan because human comfort may be regarded both physically and physiologically as a condition of thermal neutrality under which the body need not strain to reduce or increase heat loss and I believe the more natural the ventilation the better overall results for the majority of the people. Optimum winter air flow and temperature 30 FPM and  71*F and summer is 50 FPM and 76*F, so you may want to look into some type of speed control to provide air distribution all year. A comfortable employee is a happy employee and a happy employee is a productive employee...I Think :>

RE: Ventilating an unairconditioned building

(OP)
imok2 (Mechanical)
That makes sense also a larger slower fan is going to be quieter.
B.E.

RE: Ventilating an unairconditioned building

There is a tool called Psychro Tool (free download) at

http://www.squ1.com/downloads

It allows you to view the percentage of disatisfied people at a variety of conditions: temp, humidity, air velocity, activity level, clothing.

Could give you an idea of air velocities to shoot for.

RE: Ventilating an unairconditioned building

(OP)
ChrisConley (Mechanical)
I have a wet/dry-bulb thermometer and  a Psychometric chart.
 The problem I have right now is three spot coolers (Swamp type) loading the air in the building with humidity (The air is recirculating on these things) because there are not enough air exchanges on the building. The three existing exhaust fans only pull about 40,000 cfm when they are all running. There is no natural cross flow on the building. The only other source of air exchange is the roll-up shop doors which are 12'-0" wide by 18'-0" high. There are three of those all on the same side of the building. Hence the idea of mounting three 48" dia fans  just below the open eaves of the roof about 20 feet inside the shop aimed at the doors blowing out to augment the natural convective outflow through the top of the door-frame. Thereby encouraging cooler air to flow in at the bottom.
I actually need about 120,000 cfm through this building to get the heat load out of it during the worst part of the day, I know I will not quite do it with the fans, but its the best I can think of without punching holes in the building.
B.E.

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