Figure 14. Space thermal profile with Conventional Syste

To verify the results as suggested by Pignet and Saxena2 from their case study, Equation 3 was used to solve for the indoor temperature.

tiad=(tahArHah)+tsArHbhAr×(Hah+Hbh) 

Equation 3. Vertical profile of indoor air temperature 

 where,

tiad = Average indoor air temperature (AirBoss) (°F)

tah = Indoor air temperature at roof (°F)

  Ar = Roof area (ft2)

 Hah = Height above 4-way diffuser to the roof (ft)

  ts  = Space setpoint (°F)

Hbh = Height below 4-way diffuser to the floor (ft)

76°=(tah×102,300×5)+75×102,300×25102,300×(5+25)

tah=85°

 After verifying the results, the heat loss at varying outdoor air conditions can be calculated using Equation 2.  For example, the outdoor air temp is 28°, space temperature setpoint is 75°, and the roof heat transfer coefficient is 0.79, the heat loss for each system is calculated below.

 qAirBoss=0.079×102,300×(76°-28°)

 qAirBoss=387.9 MBh

 qConventional=0.079×102,300×(85°-28°)

 qConventional=460.6 MB

The heat loss through the roof is reduce by 16% using the AirBoss system.  Demonstrating destratification reduces the heat loss, a comparison of the monthly heat load for each system is calculated in Table 10 with the assumptions used in Table 9.

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