PULSE DETONATION ENGINE HAVING A SCROLL EJECTOR ATTENUATOR

• US 20140311121A1
• Filed: 10/12/2012
• Published: 10/23/2014
• Est. Priority Date: 10/12/2012
• Status: Active Grant

• Current Assignee: Raytheon Technologies Corporation d/b/a RTX (Rtx Corporation)
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: HILL, James D., CUOZZO, Michael J.
• Granted Patent: US 9,021,783 B2
• Time in Patent Office: Days
• US Class Current: 60/204
• CPC Class Codes: F02C 5/00 Gas-turbine plants characterised by the working fluid being generated by intermittent combustion
• CPC Class Codes: F02K 7/02 the jet being intermittent, i.e. pulse-jet
• CPC Class Codes: F23R 3/52 Toroidal combustion chambers
• CPC Class Codes: F23R 7/00 Intermittent or explosive combustion chambers

Abstract

The engine (10) includes at least one firing tube (12) wherein an exhaust stream (32) from the firing tube (12) drives a turbine (30). A scroll ejector attenuator (40) is secured between and in fluid communication with an outlet end (28) of the firing tube (12) and an inlet (76) of the turbine (30). The attenuator (40) defines a turning, narrowing passageway (72) that extends a distance the exhaust stream (32) travels before entering the turbine (30) to attenuate shockwaves and mix the pulsed exhaust stream (32) into an even stream with minimal temperature differences to thereby enhance efficient operation of the turbine (30) without any significant pressure decline of exhaust stream (32) pressure and without any backpressure from the attenuator (40) on the firing tube (12).

Claims

1. A pulse detonation engine comprising:

a. at least one firing tube configured to direct an exhaust stream through an outlet end of the firing tube;

b. a turbine secured in fluid communication with the outlet end of the at least one firing tube so that the exhaust stream passes into and drives the turbine; and

,

c. a scroll ejector attenuator secured in fluid communication with and between the outlet end of the at least one firing tube and the turbine, the scroll ejector attenuator defining a turning, narrowing passageway for directing flow of the exhaust stream from the outlet end of the at least one firing tube through the turning, narrowing passage and out of a discharge end of the scroll ejector attenuator adjacent an inlet of the turbine.

2. The pulse detonation engine of claim 1, wherein one of a cross-sectional area or a radius of an entry end of the turning, narrowing passage is greater than one of a corresponding cross-sectional area or a radius of the discharge end of the scroll ejector attenuator and cross-sectional areas or radii within the turning, narrowing passageway decrease between the entry end and the discharge end of the scroll ejector attenuator.

3. The pulse detonation engine of claim 1, wherein a flow length of the turning, narrowing passage is greater than an axial length of the scroll ejector attenuator, the axial length being a shortest distance between the entry passage and the discharge end of the scroll ejector attenuator, the flow length being an average distance the exhaust stream passes in transiting from the entry passage to the discharge end of the scroll ejector attenuator.

4. The pulse detonation engine of claim 1, wherein the scroll ejector attenuator includes an impact wall for re-directing flow of the exhaust stream, wherein the impact wall is configured to be tangential to a flow direction axis parallel to flow of the exhaust stream passing out of the outlet end of the firing tube.

5. The pulse detonation engine of claim 1, further comprising at least a first firing tube and a second firing tube, and an ejector portion of the scroll ejector attenuator secured between the outlet ends of the first and second firing tubes and the turning, narrowing passageway, wherein the ejector portion defines an undivided entry passage configured to receive and mix exhaust streams from, the at least first and second firing tubes.

6. The pulse detonation engine of claim 1, further comprising at least a first firing tube and a second firing tube, and an ejector portion of the scroll ejector attenuator secured between the outlet ends of the first and second firing tubes and the turning, narrowing Passageway, wherein the ejector portion defines a divided entry passage that defines at least a first entry manifold and second entry manifold configured, so that the first entry manifold receives and mixes an exhaust stream from at least the first firing tube and the second entry manifold receives and mixes an exhaust stream from at least second firing tube.

7. The pulse detonation engine of claim 6, wherein the scroll ejector attenuator defines a common passage in fluid communication with the first entry manifold and the second entry manifold, wherein the common passage is configured for receiving and mixing the exhaust streams from the first and second entry manifolds and for directing the mixed exhaust streams into the turning, narrowing passageway.

8. The pulse detonation engine of claim 1, wherein the turning passageway of the scroll ejector attenuator results in the exhaust stream exiting the discharge end of the scroll elector attenuator in a swirling orientation relative to a plane defined to be parallel to the discharge end of the scroll ejector attenuator.

9. A method of directing flow of an exhaust stream from at least one firing tube into an inlet of a turbine of a pulse detonation engine, the method comprising:

a. receiving and mixing the exhaust stream within an entry passage of a scroll ejector attenuator;

b. turning the flow of the exhaust stream from a direction of the flow of the exhaust stream exiting the at least one tiring tube to follow a flow path within a turning, narrowing passageway defined within the scroll ejector attenuator, wherein the flow path within the passageway is greater than an axial length between the entry passage and a discharge end of the scroll ejector attenuator; and

,

c. directing flow of the exhaust stream through the discharge end of the scroll ejector attenuator and into the inlet of the turbine.

10. The method of directing flow of an exhaust stream of claim 9 further comprising directing an exhaust stream from at least a first firing tube into a first entry manifold of a divided entry passage, directing an exhaust stream from at least a second entry manifold of a divided entry passage, mixing the exhaust stream from the first firing tube within the first entry manifold, mixing the exhaust stream from the second firing tube within the second entry manifold, directing flow of the first exhaust stream from the first entry manifold into a common passage, directing flow of the second entry manifold into the common passage, mixing the first exhaust stream and the second exhaust stream within the common passage, and directing flow of the mixed first and second exhaust streams through the turning, narrowing passageway of the scroll ejector attenuator.

11. The method of directing flow of an exhaust stream of claim 9 further comprising directing flow of the exhaust stream through the discharge end of the stroll ejector attenuator so that the flow of the exhaust stream swirls relative to a plane defined to be parallel to the discharge end of the scroll ejector attenuator.