Rotary kinetic fluid motors or pumps – With passage in blade – vane – shaft or rotary distributor...
Reexamination Certificate
2002-06-19
2004-03-16
Look, Edward K. (Department: 3745)
Rotary kinetic fluid motors or pumps
With passage in blade, vane, shaft or rotary distributor...
C416S09700R
Reexamination Certificate
active
06705831
ABSTRACT:
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention relates to a linked microcircuit for providing heat dissipation and film protection in moving parts. More specifically, the present invention relates to a linked microcircuit constructed to form a geometry resistant to plugging and providing both ease and superiority of fabrication.
(2) Description of Related Art
As a result of moving at high speeds through gas, moving parts such as turbines employ various techniques to dissipate internal heat as well as provide a protective cooling film over the surface of the part. One such technique involves the integration of cooling channels into the part through which cool gas can flow, absorbing heat energy, and exiting so as to form a protective film.
With reference to
FIGS. 1
a
and
1
b
, there is illustrated a cooling channel known to the art. Coolant gas
27
is circulated through the interior of a part and exits as exit gas
28
through a hole
22
permeating the part surface
12
. Gas flow
24
is pulled across part surface
12
and is illustrated herein as moving from left to right across part surface
12
. Gas flow
24
is usually generated as the result of the part moving, often in a rotary fashion, through a gas. Exit gas
28
exits the hole
22
in a direction that is substantially normal to part surface
12
. As exit gas
28
exits the hole
22
, it reacts to gas flow
24
and proceeds to move generally in the direction corresponding to the direction in which gas flow
24
is moving. As a result, exit gas
28
is pulled across the part surface
12
and tends to hug closely thereto forming a film
26
.
It is therefore advantageous to configure the placement of holes
22
through a part surface
12
such that the resulting film
26
, consisting of cool air, forms a protective coating over the part. One configuration known to the art is illustrated in
FIG. 1
c
. A plurality of holes
22
are arranged along an axis
20
wherein axis
20
extends generally perpendicular to the direction of gas flow
24
. Each hole has a width equal to break out height
16
. Pitch
18
is computed as the distance along axis
20
required for a single repetition of a hole
22
. Therefore the linear coverage afforded by such a pattern of holes is equal to break out height
16
divided by pitch
18
. As defined, coverage increases if the holes are spaced closer together (the pitch decreases) or, maintaining a constant pitch, the width of the holes
22
is increased (the break out height
16
is increased). It is therefore preferable to configure holes
22
in a pattern in such a way that the coverage is maximized. Such a configuration provides for the greatest coverage by film
26
of part surface
12
.
In addition to cooling channels formed by simple holes, microcircuits, fabricated into a part, may be used to increase the ability of the coolant gas to absorb a part's internal heat.
Microcircuits offer easy to manufacture, tailorable, high convective efficiency cooling. Along with high convective efficiency, high film effectiveness is required for an advanced cooling configuration. With reference to
FIG. 2
, there is illustrated a microcircuit
5
. Microcircuits
5
may be machined or otherwise molded within a part.
When a plurality of microcircuits is arranged to cover a part's surface, changes in the circuit channel geometry may give rise to preferable cooling properties. With reference to
FIG. 4
, there is illustrated a plurality of serpentine microcircuits
6
. As used herein, “serpentine microcircuit” refers, generally, to a microcircuit which extends over a distance by oscillating back and forth short distances in a transverse motion wherein such transverse motion is generally perpendicular to the overall direction of travel curving first left, then right, in alternating fashion. In order to increase coverage, it would be preferable to decrease the pitch
18
of the arrangement. It would prove most preferable to decrease the pitch to a degree that adjacent serpentine microcircuits
6
touch. However, were the pitch
18
to be so reduced, there would arise the unfortunate effect whereby coolant gas from one serpentine microcircuit
6
would mix with coolant gas from another serpentine microcircuit
6
traveling at a different velocity and having a different density and temperature. Such coolant gas incongruities are the result of gas streams mixing which have traveled paths of varying length and geometry.
For example, coolant gas entering at a point A travels from right to left through a serpentine microcircuit
6
by curving around to the left through point B before continuing straight and turning around to the right to point D. Were the pitch of the serpentine microcircuits
6
to be reduced such that they touched, point D′ on the uppermost serpentine microcircuit
6
would come in contact with point B of the adjacent serpentine microcircuit
6
. As has been described, coolant gas traveling past point D, and hence D′, has traveled through more turns and a greater distance than the coolant gas passing point B. As a result, the properties of the gases passing points B and D′ differ.
What is therefore needed is a method of forming a microcircuit composed of a plurality of touching, or superimposed, serpentine microcircuits thus providing a maximal coverage while reducing the incongruity of coolant gas properties present at the junctions of the component serpentine microcircuits.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an improved microcircuit design for cooling aircraft parts.
In accordance with the present invention, a linked microcircuit for providing coolant gas flow through an aircraft part, comprises at least one inlet through which a coolant gas may enter, a circuit channel extending from the at least one inlet through which the coolant gas may flow wherein the circuit channel is formed from the superimposition of a plurality of alternating serpentine circuits, and at least one outlet appended to the circuit channel through which the coolant gas may exit the circuit channel.
In accordance with the present invention, a method of fabricating an aircraft part with improved cooling flow comprises the steps of fabricating a plurality of microcircuits under a surface of the part, the microcircuits comprising at least one inlet through which a coolant gas may enter a circuit channel extending from the at least one inlet through which the coolant gas may flow wherein the circuit channel is formed from the superimposition of a plurality of alternating serpentine circuits, and at least one outlet appended to the circuit channel through which the coolant gas may exit the circuit channel, and providing a coolant gas to flow into the inlet, through the circuit channel, and out of the slot film hole.
REFERENCES:
patent: 6247896 (2001-06-01), Auxier et al.
patent: 6254334 (2001-07-01), LaFleur
patent: 6280140 (2001-08-01), Soechting et al.
Bachman & LaPointe P.C.
Edgar Richard A.
Look Edward K.
United Technologies Corporation
LandOfFree
Linked, manufacturable, non-plugging microcircuits does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Linked, manufacturable, non-plugging microcircuits, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Linked, manufacturable, non-plugging microcircuits will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3283938