Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page

# calcute earth tube in design builder How to calculate the four parameters below for earth tube ? Field: Constant Term Flow Coefficient

This number is the “A” parameter in the above earth tube equation. It is part of the user specified modifying parameters that are a function of environmental factors. This parameter, however, is a constant under all conditions and is not modified by any environmental effect. As a result, it is dimensionless. Field: Temperature Term Flow Coefficient

This number is the “B” parameter in the above earth tube equation. It is part of the user specified modifying parameters that are a function of environmental factors. This parameter is modified by the temperature difference between the outdoor and indoor air dry-bulb temperatures. The units for this parameter are inverse Celsius. Field: Velocity Term Flow Coefficient

This number is the “C” parameter in the above earth tube equation. It is part of the user specified modifying parameters that are a function of environmental factors. This parameter is modified by the speed of wind being experienced outside the building. The units for this parameter are s/m. Field: Velocity Squared Term Flow Coefficient

This number is the “D” parameter in the above earth tube equation. It is part of the user specified modifying parameters that are a function of environmental factors. This parameter is modified by square of the speed of wind being experienced outside the building. The units for this parameter are s2/m2. i donw how calcute ? i dont know how

edit retag close merge delete

Sort by » oldest newest most voted

All you need to know is explained very nice in the Engineering Reference from page 1576.

more