Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
Use the Site:GroundTemperature object. The slab preprocessor and kiva tools are intended to model a permanent structure that will greatly influence the seasonal heat flux in and out of the ground. A tent is impermanent and the ground temperature will reflect outdoor ground surface conditions. Ground temperatures are typically reported at 0.5, 2, and 4 meters. These are all too deep as you want the first few inches of ground which could exchange heat in the time the tent is there, but absent that data use the 0.5 meter temperatures.
That said, I don't think you can do this analysis without knowing ground type and conditions. There is a huge difference in heat transfer between a rock slab that was in the sun all day, a bed of pine needles, and a muddy field after a rainstorm. Moisture conditions alone will greatly influence the results. I'd suggest digging into ways to model ground surface conditions including moisture, perhaps calculating ground heat flux directly.
