One of’ t.be most. f’undament.al problems of’ f’luid dynamicswhich at.t.r·act.ed t.he at .. tent.ion of’ many researchers is t.hest.udy of’ t.wo-dimensional now past. a f’Lat, plat.e. When t.hep Lat.e is set. parallel t.o a uruf’or-m How; some analyt.icalapproaches based on Navier-St.okes equat.ions are possible,but. when it. is set. at. non-zero an€;le relat.ive t.o t.he mainsrt.r-e arn,becausebecomesit.of’becomesimpossiblet.o €;et. analyt,ical solut.iont.he equat.ions. The problemplat.e is set. near a planeparamet-er Nr2- The use 01 separat.ed boundary element-s for t.he descript.ion01 systems with mixed boundary condit-ionsFinally, in the lourth p ar-t., the potential dist.ribut.ion int.he deplet.ion region PN t.ype semiconduct.ors is obt.ained using t.heboundary solut.ion and t.he BEM .The domain Irrt.e r-g r-ed result.s in t.heBEM lormulat.ion isreduced analyt.ically to a line int.egral. The proposed method hast.he advant.age 01 reducing1- The dimensions 01 t.he problem2- The comput.at.ional t.ime .