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Update BESTEST cases based on the changes in ASHRAE 140 version 2020 #3005

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JayHuLBL opened this issue May 12, 2022 · 1 comment · Fixed by #3032
Closed

Update BESTEST cases based on the changes in ASHRAE 140 version 2020 #3005

JayHuLBL opened this issue May 12, 2022 · 1 comment · Fixed by #3032
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@JayHuLBL
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JayHuLBL commented May 12, 2022

There are following changes from version 2017 to version 2020:

  • in case 600FF
    • the infiltration rate should be adjusted for the altitude (1650 m), change the rate from 0.5 ACH to 0.414 ACH.
    • exterior surface texture should change from medium to rough
    • the Buildings.ThermalZones.Detailed.Validation.BESTEST.Data.Win600, some windows properties have changed:
      • thickness changed from 3.175mm to 3.048mm
      • the air gap changed from 13 mm to 12 mm
      • the thermal conductivity changed from 1.06 to 1 W/m.K
      • the solar transmittance changed from 0.86156 to 0.834
      • the solar reflectance changed from 0.0434 to 0.075
      • the Infrared absorptivity changed from 0.9 to 0.84
      • the u-value of the frame changed from 3 to 2.1
  • in case 640:
    • From 8:00 hours to 23:00 hours, same
    • from 23:00 hours to 7:00 hours, same,
    • but from 7:00 hours to 8:00 hours, different: the thermostat set point shall vary linearly with time from 10°C to 20°C.
  • in case 650, 650FF, 950 and 950FF:
    • the ventilation fan capacity is 1700 (not 1703.16) m3/h, and then adjusted for the altitude (1650 m). The value becomes 1409 m3/h
  • new cases since version 2020:
    • case 660: same as case 600, but with low-e window
    • case 670: same as case 600, but with single pane window
    • case 680: same as case 600, with increased wall and roof insulation
    • case 685: same as case 600, but with "20,20" Tstat (Heat=ON if Temp.>20 degC, Cool=ON if Temp.>20 degC)
    • case 695: same as case 680, but with increased wall and roof insulation with "20,20" test
    • case 680FF: same as case 680 but without mechanical heating and cooling
    • case 980: same as case 900, but with increased wall and roof insulation
    • case 985: same as case 900, but with "20,20" Tstat
    • case 995: same as 980, but with increased wall and roof insulation with "20,20" test
    • case 980FF: same as case 980, but without mechanical heating and cooling
@JayHuLBL JayHuLBL self-assigned this May 12, 2022
@JayHuLBL
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JayHuLBL commented May 13, 2022

Update:

  • the weather data changed from 724690 to 725650. See EnergyPlus weather data for Denver
  • the thermal conductivity of the air-gap in the double-pane window should change with temperature. Currently it is constant. We can set the roo.linearizedRadiation in class Buildings.ThermalZones.Detailed.Validation.BESTEST.Cases6xx.Case600FF from true (default) to false.
  • the floor is the raised floor. It assumes that the below floor air has the same temperature as ambient, but the wind speed is zero.
  • the convective heat transfer coefficient of the interior window surface should be 2.4 W/m2.K. We currently assumes it to be 4 W/m2.k (see Buildings.HeatTransfer.Windows.BaseClasses.InteriorConvectionCoefficient). -- This constant coefficient was used for the glass area with interior shade. For the BESTEST cases, there is no interior shade. So the coefficient has no impact on the results.

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