The geometrical characteristics and aerodynamic
properties of the various materials of the grain
impurity mixture are considered for effective
separation in the design of the cereal cleaner. The
lightweight materials are blown off by air blast, while
the heavier straws and stalk slide over the sieve and
fall off as over tailings. The whole grains are
separated from broken ones by the sieve
arrangement with its vibrating motion. This design
adopted some concept that separation and cleaning
should use a continuous agitation force rather than a
gravitational force and must be accompanied within a
minimum space [15]. Also a positive means of
supplying kinetic energy to the crop material is
required to loosen the bulk kernels which might be
firmly lodged inside the straw mass.