Something strange of different for windows U value Honeybee Energy Simulation

[minggangyin]

I am doing a good project about different windows U value. The result showed the more U value ,the higher cooling and dramatic heating load .

U value =2.0, the sum of cooling energy=3272kWh, the sum of heating energy=2251kWh.

U value =1.0, the sum of cooling energy=3448kWh, the sum of heating energy=1818kWh.

According to the thermal balance theory, the cooling energy should be decrease a little. And the heating energy decrease too much.

I cannot find the reason for this. Here are some image about my GH file.

Window U Value energy simulation.gh (568.4 KB)

[devang]

Hi @minggangyin,

I tried your file. I got following values for Abu_dhabi weather file.
U-value 2 Cooling = 13285.55 Heating = 168.48
U-value 1 Cooling = 11030.18 Heating = 103.49

In your file, I am not sure how you are creating U-value of 2. The sliders range that you have created will not create R-value of 0.5. I did this by simply attaching a panel with the value of 0.5 for R-value.

Also, on another note, you need to divide the thickness of material cross section by the thermal conductivity value to get a resistance value in m2K/W. I am not sure if material thickness is 1 meters as you have specified in the GH definition.

[minggangyin]

Hi @devang

I know what do you mean about the R-Value. But this discussion is about the U-Value of the glass.I am using the simple glazing definition. Could you run my GH-definition for U-Value =2.0 and 1.0 for the glass?

[devang]

Oh ok. I thought we were talking about the opaque geometry. I will run for glass and report back.