Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
THR calculated above is 1.25*TR which is as expected due to compressor heat. (CTI document here)
From the source code, Tower nominal capacity in EnergyPlus doesn't include compressor heat. Standard Design or Nominal capacity is TR only. As the documentation also says that
The "Heat Rejection Capacity and Nominal Capacity Sizing Ratio" set in the previous field is applied to this capacity to give the actual fluid cooler heat rejection at these operating conditions.
Tower nominal capacity used to be multiplied by a constant factor of 1.25 to calculate UA. Now this factor can be specified by the user using the input field mentioned above.
Tower inputs in EnergyPlus should be as shown in this catalog data. CTI uses GPM/TR and not GPM/THR and that is why EnergyPlus uses 5.382E-8 m3/s per watt used insead of 4.305E-8 m3/s per watt.
| | 2 | No.2 Revision |
THR calculated above is 1.25*TR which is as expected due to compressor heat. (CTI document here- Page 17/62)
From the source code, Tower nominal capacity in EnergyPlus doesn't include compressor heat. Standard Design or Nominal capacity is TR only. As the documentation also says that
The "Heat Rejection Capacity and Nominal Capacity Sizing Ratio" set in the previous field is applied to this capacity to give the actual fluid cooler heat rejection at these operating conditions.
Tower nominal capacity used to be multiplied by a constant factor of 1.25 to calculate UA. Now this factor can be specified by the user using the input field mentioned above.
Tower inputs in EnergyPlus should be as shown in this catalog data. CTI uses GPM/TR and not GPM/THR and that is why EnergyPlus uses 5.382E-8 m3/s per watt used insead of 4.305E-8 m3/s per watt.
