Data on the performance of fan/motor combinations used in fan-powered terminal units (FPTUs) were evaluated, and relationships were developed between fan/motor efficiency and fan total pressure as well as fan motor power and fan airflow. All fan motors were permanent split capacitor, with the speed of the motors being altered with silicon-controlled rectifiers (SCRs). Three manufacturers provided detailed experimental data on 12 fan/motor combinations employed in commercially available FPTUs. The fan motors ranged in size from 1/8 hp (93W) to 1 hp (746 W). The maximum fan airflows ranged from 690 to 4524 ft3/min (0.33 to 2.14m3/s). Data were collected by each manufacturer and provided to the authors. The performance data included SCR voltage, discharge static pressure, airflow, volts, amps, volt-amps, power factor, power, motor speed, motor size, and power divided by airflow. Data were also provided on fan discharge area and motor size. A linear relationship between fan/motor total efficiency and fan total pressure was inferred for the units evaluated. By use of the definition of “fan efficiency,” it was also shown that the relationship between fan motor power and fan airflow should also be linear. The correlations developed should be in a form that can be readily used in energy simulation programs to better estimate the performance of FPTUs.
Citation: 2015 Annual Conference, Atlanta, GA, Transactions 2015, Vol 121 pt. 2
Product Details
- Published:
- 2015
- Number of Pages:
- 9
- Units of Measure:
- Dual
- File Size:
- 1 file , 3.2 MB
- Product Code(s):
- D-AT-15-028
