b'Engineer Innovation | Aerospace & Defense0.6 20180.5 160.4 14View factor Temperature error, C12View factor to0.3 surface 10Temperature error80.2 60.1 420 020 70 120 170 220 270 320Disc Diameter, mFigure 3: Effect of lunar surface disc diameterInitial Temperature (C) Simcenter offers a space solution that includes a diurnal heating option that LatitudeFluffLayer 1Layer 2Layer 3Layer 4allows most of these effects to be 0-105-42-27-27-30included in a model. Selecting the planet fills in the form with reasonable values 30-111-52-37-39-40but these can be overridden when 45-119-62-51-51-52required. (Note that the moon is referred to as a planet in this article for 75-146-108-101-102-102convenience).85-167-142-137-137-137 A simple model was built consisting of a Table 2: Suggested initial temperatures for transient runsone meter square, vertical plate over a horizontal disk. The plate was centered on the disk with the bottom edge one meter exterior surface. A suitable heat transferabove the disk, see figure 2. Disk and plate coefficient can be determined fromwere perfect black bodies which radiated published work or from handto each other and the space environment. calculations using empirical formulae.Using the exact view factor for a small plate level with a sphere, a one meter Surface-vehicle interaction occurssquare vertical plate one meter above the because the vehicle shields part of thesurface of the moon will have a view planet surface from the solar input andfactor to the lunar surface of 0.4993. If the the Infrared (IR) emissions from thelunar surface is at 400 kelvin (K), (typical vehicle can cause local heating of themaximum at the equator), the plate will planet surface. On Earth, thebe at 336.2K. The model was solved for atmosphere and moisture in the soilvarious diameters of disk and the average moderate these effects, but on a planetplate temperature determined and used with no atmosphere and a low thermalto calculate the view factor to the disk. conductivity regolith these effects can beThe results are shown in figure 3. For the significant. equatorial region a disk diameter of about 38'