This assumes that all the air is cooled to 12.7 C saturated. In real life only part of the air volume gets in touch with the cooling coils which would be at a T lower than 12.7 (and therefore cools down to saturation point). This will mix with the remaining air volume and therefore the final point for the entire air volume is somewhere in the middle. You don’t supply air at 100% RH to a room.
The fresh air percentage is not what I was questioning. Your final point is shown on the saturation line, so assumes that the full fresh air volume is at 100% relative humidity. This is not possible in reality, as not all the air volume will actually touch the coils. The final point would have a lower relative humidity. In your data sheet it says that the resulting RH at 12.7 C is 45%. This is more realistic. Thanks anyway.
I think the calculation is wrong if first the Flow rate is in M3/min and not M3/s. if you multiply (H1-H2)* Mass flow rate, we do not get the same result as you. Can you please clarify.
Answer and Calculation is correct, i just put it kg/s instead of kg/min, i already used conversation factor in Q Calculation. If you convert cfm in to m3/sec than no need to put coversion factor in Q calculation Thank you.
If the air at dry bulb temp at 36 deg C and RH at 42 %, can i cool the air at 11 deg C by directly adding chilled water into air through evaporatorive cooler. What will be the required sprayed chilled water temp and flow rate? Can we use chilled water at 7 deg c And what is the chiller load TR of makeup chilled water?
In HAP generated report it shows that 4.9 ton coil load is required, then why did you calculated it by manual method.it is my doubt, if u can please tell me
Some conditions are different, HAP calculation was based on VAV system and manual calculation is done to check that what will be the coil load on 100 fresh air at 106 F that is cool down to 55 F.
Wrong concept,It is easily understandable your line is crossing outside of 100% RH ,which is not possible.Pls haveva proper knowledge before you put video on youtube.
Thanks. Good explanation. We use British units over here in the US. But, still very helpful.
This assumes that all the air is cooled to 12.7 C saturated. In real life only part of the air volume gets in touch with the cooling coils which would be at a T lower than 12.7 (and therefore cools down to saturation point). This will mix with the remaining air volume and therefore the final point for the entire air volume is somewhere in the middle. You don’t supply air at 100% RH to a room.
The method shown in video is for 100% fresh air.
The fresh air percentage is not what I was questioning. Your final point is shown on the saturation line, so assumes that the full fresh air volume is at 100% relative humidity. This is not possible in reality, as not all the air volume will actually touch the coils. The final point would have a lower relative humidity. In your data sheet it says that the resulting RH at 12.7 C is 45%. This is more realistic. Thanks anyway.
sir how is it possible that outside air DB is 41 and WB is 87 centigrade? not cleared that part
I think the calculation is wrong if first the Flow rate is in M3/min and not M3/s. if you multiply (H1-H2)* Mass flow rate, we do not get the same result as you. Can you please clarify.
Answer and Calculation is correct, i just put it kg/s instead of kg/min, i already used conversation factor in Q Calculation. If you convert cfm in to m3/sec than no need to put coversion factor in Q calculation
Thank you.
Sir please make a video on how to calculate U value for heat load
Sir plz calculate capacity of cooling coil using mcquay psychrometric analyzer
If the air at dry bulb temp at 36 deg C and RH at 42 %, can i cool the air at 11 deg C by directly adding chilled water into air through evaporatorive cooler.
What will be the required sprayed chilled water temp and flow rate?
Can we use chilled water at 7 deg c
And what is the chiller load TR of makeup chilled water?
Q= 1.08xcfmxDeltT
You will get the sensible heat.
sir why you take 50% RH? you not considered WB 87 centigrade
In HAP generated report it shows that 4.9 ton coil load is required, then why did you calculated it by manual method.it is my doubt, if u can please tell me
Some conditions are different, HAP calculation was based on VAV system and manual calculation is done to check that what will be the coil load on 100 fresh air at 106 F that is cool down to 55 F.
Nice
why you chosen 50% RH
From where you bring this number boss ?
It depends on your space, normally we consider 50%.
i did calculation by your metod but answer comes wrong and have checked your answer which is also
wrong .
Only mistake is unit, its kg/min and i used conversation factor in Q calculation
Hi, you made a mistake. 34.72 m3/min / 0.925 m3/kg = 37.53 kg/min and not kg/s ;)
Yes, just unit mistakes but calculations are right,there is conversion factor already added in excel file.
Appreciate your comment
Did not understand
which part?
Wrong concept,It is easily understandable your line is crossing outside of 100% RH ,which is not possible.Pls haveva proper knowledge before you put video on youtube.
It's just an example to show the calculations, it depends upon your parameters.
Thank you