BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI - Universitatea ...

BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI
Publicat de
Universitatea Tehnică „Gheorghe Asachi” din Iaşi
Tomul LVI (LX), Fasc. 2, 2010
Secţia
CONSTRUCȚII DE MAȘINI
PROPOSALS FOR THE IMPROVEMENT OF
THE FLUIDIC SPIRAL JETMILLS' ACTIVITY
BY
ILEANA FULGA 1 and EUGEN STRAJESCU 2
Abstract. In this paper is presented a documentary study about the particle
size reduction. There are presented the authors' realizations concerning the
optimization of the spiral jetmills produced in the APTM Enterprises, based on a
new mathematical and experimental model of the flows, developed by the authors.
There are presented conclusions about the research directions to be attacked in the
future.
Key words: micronization, spiral jetmills, fluidic mills, optimization.
1. Introduction
The fluidic mills are the single equipments that permit the dry grinding and
the get of an ultra fine granulometry (1-25 μm), indifferent by the product
resistance and by the hardness of the product's crystals.
The grinding is produced by the collision between the particles that are
accelerated at very high speeds in flows and gas jets, or by their impact with
solid surfaces (fixed or mobile) from the interior of the milling room.
We consider important to signalize that the real or as a rough guide speeds of
the entrainment and grinding particles' jets are considered secret and can not be
found in the literature. At this moment exist in the world 7 fabricants that
produce fluidic mills. In fact, there are many societies that commercialize
fluidic mills, but they are procuring the equipments offered from one of the
mentioned fabricants.
All the fluidic mills fabricants consider strictly confidential any data
concerning the sizing and the calculus of these equipments from the point of
view of the fluidic mechanics, refusing to give any theoretical or experimental
value concerning the geometry of the fluidic nozzle the jets' speeds and
particles' speeds or values bound of the fluidic grinding process.