COMPARISON OF THE NASCAP/GEO, SEE INTERACTIVE CHARGING HANDBOOK, AND NASCAP-2K.1 SPACECRAFT CHARGING CODES

The NASA Charging Analyzer Program (NASCAP) spacecraft charging software developed by Maxwell Technologies has been widely used for the past fifteen to twenty years in satellite design and investigation of spacecraft charging related anomalies. NASCAP/GEO, the version used for geostationary orbiting satellites, solves the Poisson-Vlasov system for currents and densities taking into account the limited speed and memory of computer systems standard for the day. In addition, use of this charging model requires individual input files that are not readily transported into the various families of charging codes to facilitate comparison of results by the user. This paper presents comparison of spacecraft charging results obtained for a hypothetical satellite using the current versions of NASCAP/GEO, SEE Handbook, and NASCAP 2K/GEO. The model satellite is constructed of materials typically used for building geosynchronous satellites. Comparison of the codes is accomplished by using the same hypothetical satellite model in all three charging codes. Differences and similarities of the resulting output for each of the three codes will be presented, along with a discussion of the computational efficiency and ease of use for each of the codes.