In hypersonic/supersonic flow conditions, numerical simulations, experience relations and experiment analysis are made to study thermal-environment distribution characteristic around local-parts imposed by protuberance interacting body. Comparing flow characteristic structures in different shape, height, breadth ere, we found that interaction-zone size induced by high protuberance depend sensitively on effective breadth and short protuberance interaction-zone size depend on protuberance height. On the other hand, interaction-zone size is imposed by shade of lead edge, whether laminar or turbulence. Square-lead-surface and arc lead surface separation length ratio is 1.414. Sweepback affects separation length. A correlative line is built for size of separation imposed by sweepback.