Pulsed detonation engine

Patent metadata

Field	Value
Publication number	US-9909533-B2
Application number	US-201213561074-A
Country	US
Kind code	B2
Filing date	Jul 29, 2012
Priority date	Jul 29, 2011
Publication date	Mar 6, 2018
Grant date	Mar 6, 2018

Abstract

A pulsed detonation engine may include a detonation tube for receiving fuel and an oxidizer to be detonated therein, one or more fuel-oxidizer injectors for injecting the fuel and oxidizer into the detonation tube, one or more purge air injectors for injecting purge air into the detonation tube for purging the detonation tube, and an ignition for igniting the fuel and oxidizer in the detonation tube so as to initiate detonation thereof. The detonation tube has an upstream end, a downstream end, and an axially extended portion extending from the upstream end to the downstream end and having a perimeter. The fuel-oxidizer injectors and purge air injectors may be disposed at least along the axially extended portion. The ignition may include a plurality of igniters disposed at or near the perimeter of the axially extended portion, spaced about the perimeter, at or near the upstream end of the detonation tube.

First claim

What is claimed is:

1. A method of operating a pulsed detonation engine comprising:
providing a pulsed detonation engine comprising:
a detonation tube configured to receive gaseous fuel and an oxidizer to be detonated therein, wherein the detonation tube comprises a perimeter wall, an upstream end, a downstream end, a longitudinal axis extending from the upstream end to the downstream end, and an axially extended portion extending along the longitudinal axis from the upstream end to the downstream end;
one or more fuel-oxidizer injectors configured to inject the gaseous fuel and the oxidizer into the detonation tube, wherein the one or more fuel-oxidizer injectors are disposed at the upstream end and the perimeter wall along the axially extended portion of the detonation tube, wherein the one or more fuel-oxidizer injectors defines an array of orifices having a central orifice and a plurality of elongate orifices substantially surrounding the central orifice, wherein the central orifice is defined at the geometric center of the one or more fuel-oxidizer injectors, wherein the central orifice has a central orifice axis perpendicular to the longitudinal axis of the detonation tube, wherein each of the plurality of elongate orifices defines an elliptical shape or an elongated circle shape and has an orifice axis at an acute angle relative to the central orifice axis, wherein the central orifice is configured to inject the gaseous fuel and oxidizer in a radial direction and wherein the elongate orifices are configured to inject the gaseous fuel and oxidizer in a direction having an axial and radial component into the detonation tube; and
an ignition configured to ignite the gaseous fuel and the oxidizer in the detonation tube so as to initiate detonation of the gaseous fuel and the oxidizer;

injecting the gaseous fuel and the oxidizer into the detonation tube via the one or more injectors; and
igniting the gaseous fuel and the oxidizer in the detonation tube so as to initiate detonation of the gaseous fuel and the oxidizer, wherein the gaseous fuel and the oxidizer are injected into the detonation tube both from the upstream end and along the axially extended portion of the detonation tube.

2. The method according to claim 1 , wherein at least one of the one or more fuel-oxidizer injectors is disposed along the axially extended portion and is inclined toward the downstream end of the detonation tube, and wherein the gaseous fuel and the oxidizer are injected into the detonation tube at least partly in a downstream direction of the detonation tube.

3. The method according to claim 1 ,
wherein the axially extended portion extends also from the longitudinal axis, at any point thereon, in a direction perpendicular to the longitudinal axis, to the perimeter wall,
wherein at least two of the one or more fuel-oxidizer injectors are disposed along the axially extended portion of the detonation tube at different angular positions on the perimeter wall, and
wherein the gaseous fuel and the oxidizer are injected into the detonation tube from different angular positions on the perimeter wall of the detonation tube.

4. The method according to claim 1 ,
wherein one of the one or more fuel-oxidizer injectors is an upstream fuel-oxidizer injector and another one of the one or more fuel-oxidizer injectors is a downstream fuel-oxidizer injector, wherein a first longitudinal distance between the upstream fuel-oxidizer injector and the upstream end is smaller than a second longitudinal distance between the downstream fuel-oxidizer injector and the upstream end,
wherein the pulse detonation engine further comprises, for each of the fuel-oxidizer injectors, a valve corresponding thereto configured to control the injection of the gaseous fuel and the oxidizer from the respective fuel-oxidizer injector into the detonation tube, and, for each of the valves, a controller corresponding thereto configured to control the respective valve so as to adjust the timing of the injection from the fuel-oxidizer injector corresponding to the respective valve, whereby phased injection may be performed, the phased injection comprising injecting of the gaseous fuel and the oxidizer into the detonation tube from the upstream fuel-oxidizer injector and, after commencement of the injecting from the upstream fuel-oxidizer injector, injecting of the gaseous fuel and the oxidizer into the detonation tube from the downstream fuel-oxidizer injector, and
wherein the gaseous fuel and the oxidizer are injected into the detonation tube first from an upstream fuel-oxidizer injector and, after commencement of the injecting from the upstream fuel-oxidizer injector, from a downstream fuel-oxidizer injector.

5. A pulsed detonation engine, comprising:
a detonation tube configured to receive gaseous fuel and an oxidizer to be detonated therein, wherein the detonation tube comprises a perimeter wall, an upstream end, a downstream end, a longitudinal axis extending from the upstream end to the downstream end, and an axially extended portion extending along the longitudinal axis from the upstream end to the downstream end;
a fuel-oxidizer premix chamber configured to premix the gaseous fuel and oxidizer prior to entry of the gaseous fuel and oxidizer into the detonation tube;
one or more fuel-oxidizer injectors configured to uniformly inject the pre-mixed gaseous fuel and the oxidizer from the pre-mix chamber into the detonation tube, wherein the one or more fuel-oxidizer injectors are disposed at the upstream end and along the axially extended portion of the detonation tube, wherein the one or more fuel-oxidizer injectors defines an array of orifices having a central orifice and a plurality of elongate orifices substantially surrounding the central orifice, wherein the central orifice has a central orifice axis perpendicular to the longitudinal axis of the detonation tube, wherein each of the plurality of elongate orifices defines an elliptical shape or an elongated circle shape and has an orifice axis at an acute angle relative to the central orifice axis, wherein the central orifice is configured to inject the pre-mixed gaseous fuel and oxidizer in a radial direction and wherein the elongate orifices are configured to inject the pre-mixed gaseous fuel and oxidizer in a direction having an axial and radial component into the detonation tube; and
an ignition configured to ignite the pre-mixed gaseous fuel and the oxidizer in the detonation tube so as to initiate detonation of the pre-mixed gaseous fuel and the oxidizer.

6. The pulsed detonation engine according to claim 5 ,
wherein the detonation tube comprises (a) a height extending in a vertical direction perpendicular to the longitudinal axis, and (b) a width extending in a horizontal direction perpendicular to the longitudinal axis, and
wherein at least one of the one or more fuel-oxidizer injectors is disposed along the axially extended portion and is inclined relative to the vertical direction and/or the horizontal direction.

7. The pulsed detonation engine according to claim 5 , wherein at least one of the one or more fuel-oxidizer injectors is disposed along the axially extended portion and is inclined toward the downstream end of the detonation tube.

8. The pulsed detonation engine according to claim 5 , wherein the axially extended portion extends also from the longitudinal axis, at any point thereon, in a direction perpendicular to the longitudinal axis, to the perimeter wall, and wherein at least two of the one or more fuel-oxidizer injectors are disposed along the axially extended portion of the detonation tube at different angular positions on the perimeter wall.

9. The pulsed detonation engine according to claim 5 , wherein the a

Assignees

• Lu Frank K
• Wilson Donald R
• Univ Texas

Inventors

• Lu Frank K
• Wilson Donald R

Classifications

• F23C2205/10

  with pulsating fuel supply · CPC title

• F02K7/067

  having aerodynamic valves · CPC title

• F02C5/11

  using valveless combustion chambers · CPC title

• Y02T50/671

  Cross-Sectional Technologies · mapped topic

• F02K7/02 Primary

  the jet being intermittent, i.e. pulse-jet · CPC title