the ergun equation,derived by the tu**sh chemical engineer sabri ergun in 1952,expresses the friction factor in a packed column as a function of the reynolds number: fp=150/grp+1.7555 where fp and grp are defined as fp=(δp/l)·[dp/(ρ·vs²)]·[ε³/(1-ε)]and grp=(dp·vs... 20210311