7. Conclusion
Effect of apex cone angle on particle separation performance was
examined by use of experimental and CFD studies and the following
conclusions are obtained.
(1) The optimum apex cone angle was 70° under the low inlet
velocity condition. By use of this apex cone angle, the minimum
value of 50% cut size was obtained.
(2) From the flow visualization method by the use of soap foam,
the upward flow and downward flow coexisted on the surface
of the cone angle of 70°. The clear separation line between
upward and downward flows is observed by use of this special
apex cone.
(3) The effect of apex cone angle on particle separation performance
becomes small under the high inlet velocity condition.
Because nearly all particles are moving in places away from the
apex cone, then the particle separation performance is not
affected by changes of the apex cone angle.
(4) The particle separation performance and flow visualization
results qualitatively agreed with the 3-dimentional CFD