Supercritical　water　fluidized　bed　(SCWFB)　is　a　novel　reactor　which　can　achieve　efficient　and　clean　gasification　of　biomass.　The　study　of　supercritical　water　(SCW)-solid　two-phase　flow　characteristics　in　SCWFB　is　of　great　significance　for　biomass　conversion　and　optimization　of　the　reactor.　However,　the　work　on　the　drag　coefficient　of　single　biomass　particle　and　biomass　particle　cluster　has　limitations　to　describe　the　interactions　between　particles　accurately.　In　this　paper,　two-particle　model　was　used　to　study　the　drag　coefficient　and　flow　characteristics　of　supercritical　water　flow　past　biomass　particle　cluster　in　the　range　of　10＜Re＜200.　The　simulation　results　show　the　interactions　between　particles　can　transmit　larger　distances　perpendicular　to　the　flow　field　at　low　Re.　Drag　coefficient　of　particles　is　mainly　affected　by　the　wake　zone　generated　behind　the　upstream　particles　and　nozzle　effect　between　particles.　Nozzle.　effect　which　is　significant　at　high　Re　will　promote　flow　separation　and　make　form　drag　and　friction　drag　increase.　And　the　wake　zone　generated　behind　the　upstream　particles　has　the　opposite　effect.　(C)　2019　Elsevier　Ltd.　All　rights　reserved.