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Control cooling capacity using radiant system.

Hi, I'm trying to model a radiant surface for floor cooling and I would like to limit the floor cooling at 20W/m2. As the Cooling capacity of the system is controlled by : Tin , dT and the flow rate.

Right now I'm trying to keep the Tin , dT fixed and vary the flow rate to achieve the 20W/m2. Supply temperature Tin : 18deg.C dT : 4 deg.C

Area of the apartment : 88m2 - > 88*20W/m2 - > 1760 W

By the formula Volume flowrate has to be : 0.000106 m3/s.

But, as expected the even though the flow rate is controlled the system still has high cooling capacity. So, I started tweaking (reducing) the flow rate until I reached close to an acceptable cooling capacity (20w/m2) The final flowrate : 0.00004 m3/s.

Is this how we can control the cooling capacity or do you suggest any alternative methods ? and why does the cooling capacity is way more then 1760 W even with the calculated flow rate (0.000106m3/s) ?

Please let me know if it is not clear.

Regards, Prethvi Raj, Building Performance Analyst, TRAJECT 361.

 2 retagged __AmirRoth__ 4436 ●5 ●17 http://bleedinggreenna...

Control cooling capacity using radiant system.

Hi, I'm trying to model a radiant surface for floor cooling and I would like to limit the floor cooling at 20W/m2. As the Cooling capacity of the system is controlled by : Tin , dT and the flow rate.

Right now I'm trying to keep the Tin , dT fixed and vary the flow rate to achieve the 20W/m2. Supply temperature Tin : 18deg.C dT : 4 deg.C

Area of the apartment : 88m2 - > 88*20W/m2 - > 1760 W

By the formula Volume flowrate has to be : 0.000106 m3/s.

But, as expected the even though the flow rate is controlled the system still has high cooling capacity. So, I started tweaking (reducing) the flow rate until I reached close to an acceptable cooling capacity (20w/m2) The final flowrate : 0.00004 m3/s.

Is this how we can control the cooling capacity or do you suggest any alternative methods ? and why does the cooling capacity is way more then 1760 W even with the calculated flow rate (0.000106m3/s) ?

Please let me know if it is not clear.

Regards, Prethvi Raj, Building Performance Analyst, TRAJECT 361.