CN100507253C - A multi-tube pulse detonation combustion chamber and its detonation method - Google Patents

Abstract

The invention discloses a multi-tube pulse detonation combustion chamber and the detonation method. A detonation chamber inlet opening, a detonation jet flow inlet opening, a detonation jet flow outlet opening and a detonation chamber outlet opening are poditioned in sequence on the detonation chamber, the detonation jet flow outlet opening is connected with the detonation jet flow inlet opening of the adjacent detonation unit, and a plurality of detonation units are connected to form a circular combustion chamber with a plurality of detonation chamber inlet opening and a plurality of detonation chamber outlet opening. The detonation starting device is positioned on the detonation chamber of one of the detonation units. When the detonative gas mixture is filled in the whole detonation chamber 2 through the detonation chamber inlet opening 1 of each detonation unit under the same condition, the detonation starting device 6 of the invention begins to work. The invention realizes the multi-tube pulse detonation combustion chamber with very high working frequency without the dependency of the high energy and high frequency ignition system, and the invention can be used to replace the main combustion chamber or booster combustion chamber of the existing gas-turbine engine, or the combustion chamber of the rotating ramjet engine.

Description

A multi-tube pulse detonation combustion chamber and its detonation method

technical field

The invention relates to the field of power, in particular to a pulse detonation combustion chamber and its detonation method.

Background technique

There are two kinds of combustion waves in nature: one is deflagration wave and the other is detonation wave. The detonation wave propagates toward the unburned mixture at a speed of several kilometers per second. A detonation wave is essentially a shock wave followed by a combustion wave. The detonation wave can generate extremely high gas pressure (greater than 15 to 55 atmospheres) and gas temperature (greater than 2800K). Due to the extremely fast propagation speed of the detonation wave, the subsequent combustion process can be regarded as a constant volume combustion process, so its combustion efficiency very high. Due to the high efficiency of the pulse detonation cycle, and the pulse mode of operation, this makes it very attractive for propulsion systems. When the working frequency reaches a higher frequency, it can be considered to be able to generate a stable thrust, which is generally required to be above 100Hz. Therefore, how to increase the operating frequency of the pulse detonation engine is the direction that many researchers are working on.

The pulse detonation engine of the classic cycle process is open at one end, and the mixture of fuel and oxidant is injected intermittently at the other end, and then ignited and detonated. The detonation wave is transmitted out of the detonation chamber, and then filled with isolation gas to enter the next cycle.

This type of engine usually requires a high-energy capacitor ignition system or the transient plasma ignition system that has just emerged. The large pulse energy demand of the capacitor ignition system usually exceeds 2000J, and the plasma ignition system usually requires 1-10J. Since each cycle requires Ignition and high-frequency operation require a very large power, exceeding several thousand watts. The key problem is that these two systems are difficult to miniaturize and lighten. When the diameter of the detonation chamber is large, it is difficult to quickly form a detonation wave even if a high-energy electric ignition system is used. In order to detonate quickly, a detonator tube appears. The detonator itself is a complex pulse detonation rocket engine system, which is also inseparable from the electric ignition system and independent gas isolation system. Thus, pulse detonation engines using detonators are more complex. For the air-breathing pulse detonation engine, due to the dilution of nitrogen in the air, the sensitivity of the mixture is greatly reduced, the energy and power required for direct detonation are greatly increased, and the economy of direct detonation is reduced. If a low-energy ignition source is used, the ignition delay time is greatly increased, and the distance and time for the transition from deflagration to detonation are also very long.

Contents of the invention

In order to overcome the disadvantage that the pulse detonation combustion chamber in the prior art relies heavily on a high-power pulse ignition unit, the present invention provides a multi-tube pulse detonation combustion chamber, which can work at high frequency without a pulse ignition source.

The invention also provides a detonation method related to the multi-tube pulse detonation combustion chamber.

The technical solution adopted by the present invention to solve the technical problem is: comprising multiple sets of detonation units, each unit comprising a detonation chamber inlet 1, a detonation jet inlet 4, a detonation chamber 2, a detonation jet outlet 5, and a detonation chamber outlet 3 And start the detonation device 6, the detonation chamber inlet 1 and the detonation chamber outlet 3 are located at both ends of the detonation chamber 2, the detonation chamber inlet 1 is at the most upstream, the detonation jet inlet 4 is close to and located downstream of the detonation chamber inlet 1, the detonation jet The outlet 5 is close to and located upstream of the detonation chamber outlet 3, the detonation jet outlet 5 is connected with the detonation jet inlet 4 of the next adjacent detonation unit, after multiple detonation units are connected, the detonation jet outlet 5 of the last detonation unit and Initially, the detonation jet inlets 4 of the detonation units are connected end to end to form a circular combustion chamber with multiple detonation chamber inlets 1 and multiple detonation chamber outlets 3 . The detonating jet outlet 5 and the detonating jet inlet 4 connected together form a jet propagation pipe 8 . The starting detonation device 6 is installed on the detonation chamber 2 of one of the detonation units.

The detonation method of the present invention is that when the detonation chamber inlets 1 of all detonation units have detonable mixed gas to fill the whole detonation chamber 2 with the same conditions, start the detonation device 6 to work to form a detonation wave propagating downstream, After the detonation wave propagates to the detonation jet outlet 5, most of the detonation wave is discharged through the detonation chamber outlet 3, and a part of the detonation wave propagates to the detonation jet inlet 4 of the next detonation unit through the detonation jet outlet 5, so that the detonation of the next detonation unit A detonation wave is rapidly formed in the detonation chamber 2, and the detonation wave rapidly propagates downstream in the detonation chamber 2 to the detonation jet outlet 5, so that it is continuously transmitted downstream. For a single detonation unit, when the detonation wave is discharged from the detonation chamber outlet 3, there will be an expansion wave propagating from the detonation chamber outlet 3 to the detonation chamber inlet 1, so that the pressure in the detonation chamber drops, and the pressure drops After reaching a certain value, the combustible mixture rushes into the detonation chamber inlet 1 again, and a new round of filling process of the detonation unit begins. When the detonation wave propagates to the detonation jet outlet 5 of the last detonation unit, it returns to the detonation unit equipped with the detonation device 6. At this time, the detonation unit equipped with the detonation device 6 has completed exhaust gas discharge and detonation mixing. During the gas filling process, the detonation jet flow into the detonation chamber 2 of the unit quickly forms a detonation wave, and the detonation device 6 is no longer working. In this way, for a single detonation unit, its working cycle is equal to the time difference of the detonation jet entering the detonation jet inlet 4 of the adjacent detonation unit multiplied by the number of detonation units in the group of combustion chambers. The number of detonation units in the combustion chamber depends on the ratio of the time required for the detonation mixture to fill the detonation chamber 2 to the gas expansion time in the detonation chamber 2, and usually requires more than 4-6 units under subsonic combustion conditions detonation unit. For all the detonation units in the combustion chamber of the present invention, no external ignition system is needed after detonation, and the detonation wave can propagate itself in the combustion chamber without extinguishing, relying on the mode of sequential propagation among closed multi-tubes, using the combustion chamber detonation to burn itself The energy generates a high-frequency detonation wave jet to realize the single-tube high-frequency pulse work.

As the first preferred solution of the present invention, when the number of a group of detonation units is N times of a certain integer M, start detonation devices can be installed on the N detonation units separated by M-1 detonation units 6. When starting, detonate N starting detonating devices 6 at the same time, and there can always be N detonation waves chasing each other, and at the same time, the flow state and the force on the combustion chamber can be evenly distributed in the circumferential direction of the multi-tube annular combustion chamber.

As the second preferred solution of the present invention, multiple rings of multi-tube annular combustion chambers can be radially arranged in the multi-tube annular combustion chamber, so that they are coaxially connected in parallel, and the windward area of the incoming flow can be more effectively utilized. At least one detonation unit in each circle is equipped with a starting detonating device 6 and the number of starting detonating devices in each circle is the same, and the starting detonating devices in each circle are evenly distributed in the circumferential direction.

As the third preferred solution of the present invention, at the detonation jet inlet 4 of the detonation unit equipped with the detonation device 6, a start valve 7 is installed to ensure that the combustion wave will not detonate upward from the jet propagation pipe 8 when starting unit propagation. When the starting detonation device 6 works, the starting valve 7 is closed, and after the detonation wave is formed in the upstream detonation chamber 2 of the starting valve 7, the starting valve 7 is opened, and remains normally open when the combustion chamber is working normally.

As the fourth preferred solution of the present invention, the multi-tube annular combustion chamber of the present invention can be installed on a rotating shaft 9, and the rotating shaft of the multi-tube annular combustion chamber itself coincides with the rotating shaft 9, relying on the detonation chamber The exhaust jet flow generated by 2 drives the entire combustion chamber to rotate, and the rotating combustion chamber makes the flow conditions at the entrance 1 of the detonation chamber more favorable.

A kind of preferred scheme of detonation method of the present invention is, when the detonation chamber inlet 1 of all detonation units has detonable mixed gas to be full of whole detonation chamber 2 with identical condition, close start valve 7, start detonation device 6 After the detonation wave propagates to the detonation jet outlet 5, most of the detonation wave is discharged through the detonation chamber outlet 3, and a part of the detonation wave propagates to the detonation jet inlet 4 of the next detonation unit through the detonation jet outlet 5 , so that a detonation wave is rapidly formed in the detonation chamber 2 of the next detonation unit, and the detonation wave rapidly propagates downstream in this detonation chamber 2 to the detonation jet outlet 5, so that it is continuously transmitted downstream. For a single detonation unit, when the detonation wave is discharged from the detonation chamber outlet 3, there will be an expansion wave propagating from the detonation chamber outlet 3 to the detonation chamber inlet 1, so that the pressure in the detonation chamber drops, and the pressure drops After reaching a certain value, the combustible mixture rushes into the detonation chamber inlet 1 again, and a new round of filling process of the detonation unit begins. In addition, in the expansion stage, since the downstream detonation chamber has already formed a detonation wave, the burned gas will reversely spray back from the downstream detonation chamber through the jet propagation pipe 8 . After the detonation wave is formed in the upstream detonation chamber 2 of the starting valve 7, the starting valve 7 is opened, and when the detonation wave propagates to the starting valve 7, it returns to the detonation unit equipped with the starting detonating device 6. At this time, the starting detonating device 6 is equipped with The detonation unit has completed the exhaust gas discharge and the filling process of the detonable gas mixture. After the detonation jet enters the detonation chamber 2 of the unit, a detonation wave is formed rapidly, and the detonation device 6 is no longer working. In this way, for a single detonation unit, its working cycle is equal to the time difference of the detonation jet entering the detonation jet inlet 4 of the adjacent detonation unit multiplied by the number of detonation units in the group of combustion chambers. The number of detonation units in the combustion chamber depends on the ratio of the time required for the detonation mixture to fill the detonation chamber 2 to the gas expansion time in the detonation chamber 2, and usually requires more than 4-6 units under subsonic combustion conditions detonation unit. And the starting valve 7 keeps the normally open state when the combustion chamber works normally.

The beneficial effects of the present invention are: the detonation method of the present invention makes the detonation wave detonation close to direct detonation, and the residence time of the combustion wave in the detonation chamber 2 is very short. Experiments show that when the distance between the detonation jet inlet 4 and the detonation jet outlet 5 of the detonation unit is 0.8m, the time difference between the detonation wave entering the detonation jet inlet 4 of the adjacent detonation unit is about 1.2ms, so four such detonation units consist of The single-tube operating frequency of the multi-tube detonation combustor can exceed 200 Hz, and the single-tube operating frequency of the multi-tube detonation combustor composed of 8 such detonation units can also exceed 100 Hz. The present invention obtains a multi-tube pulse detonation combustor that can obtain a very high operating frequency without relying on a high-energy high-frequency pulse ignition system, and can be used to replace the main combustion chamber and afterburner of an existing gas turbine, or as a rotary ramjet combustion chamber.

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Description of drawings

Fig. 1 is a schematic diagram of the start-up process of the present invention;

Fig. 2 is a schematic diagram of the working process of the present invention;

Fig. 3 is a structural diagram of Embodiment 1 of the present invention;

Fig. 4 is the structural diagram of embodiment 2 of the present invention;

Fig. 5 is a structural diagram of Embodiment 3 of the present invention.

In the figure, 1-detonation chamber entrance, 2-detonation chamber, 3-detonation chamber exit, 4-detonation jet inlet, 5-detonation jet outlet, 6-start detonation device, 7-start valve, 8-jet propagation Tube.

Detailed ways

Device Embodiment 1: Referring to Figure 3, it includes 6 detonation units connected together through the jet propagation tube 8 to form a circular multi-tube pulse detonation combustion chamber, each detonation unit includes a detonation chamber inlet 1. The detonation chamber 2, the detonation chamber outlet 3 and the jet propagation pipe 8, the jet propagation pipe 8 includes the detonation jet outlet 5 of the upper detonation unit connected together and the detonation jet inlet 4 of the lower detonation unit , the detonation chamber inlet 1 and the detonation chamber outlet 3 are located at both ends of the detonation chamber 2, the detonation chamber inlet 1 is the most upstream, the detonation jet inlet 4 is close to and located downstream of the detonation chamber inlet 1, and the detonation jet outlet 5 is close to and located at Upstream of the outlet 3 of the detonation chamber, after multiple detonation units are connected, a situation of end-to-end connection is formed. One of the detonation units is equipped with a starting detonation device 6, and a starting valve 7 is installed on the jet propagation pipe 8 upstream of the detonation unit. The detonable mixture flows into the detonation chamber 2 along the direction perpendicular to the detonation chamber inlet 1, and when the detonation chamber inlet 1 of all detonation units has the detonable mixture filling the entire detonation chamber 2 under the same conditions, it is closed Start the valve 7, start the detonation device 6 to work, and form a detonation wave that propagates downstream. After the detonation wave propagates to the jet propagation pipe 8, most of the detonation wave is discharged through the detonation chamber outlet 3, and a part of the detonation wave propagates to the next one through the jet propagation pipe 8. In the detonation chamber 2 of the detonation unit, a detonation wave is rapidly formed, which is continuously transmitted, and the detonation wave propagates to the detonation jet outlet 5 of the last detonation unit, and then returns to the detonation unit equipped with the detonation device 6, and the start-up The valve 7, the detonation unit equipped with the detonation device 6 has completed the exhaust gas discharge and the filling process of the detonable gas mixture. After the detonation jet enters the detonation chamber 2 of the unit, a detonation wave is formed rapidly, and the detonation device 6 is activated. no longer work. Thereafter, the combustion chamber enters a stable cycle, no external ignition equipment is needed, and the starting valve 7 is normally open.

Device embodiment 2: referring to Fig. 4, it includes two ring-shaped multi-tube pulse detonation combustion chambers, and each ring of multi-tube pulse detonation combustion chambers is respectively connected together by 6 detonation units through the jet propagation pipe 8, Each detonation unit includes a detonation chamber inlet 1, a detonation chamber 2, a detonation chamber outlet 3 and a jet propagation pipe 8, and the jet propagation pipe 8 includes the detonation jet outlet 5 and the lower detonation jet outlet of the upper detonation unit connected together. The detonation jet inlet 4 of the primary detonation unit, the detonation chamber inlet 1 and the detonation chamber outlet 3 are located at both ends of the detonation chamber 2, the detonation chamber inlet 1 is at the most upstream, and the detonation jet inlet 4 is close to and located at the detonation chamber entrance Downstream of 1, the detonation jet outlet 5 is close to and located upstream of the detonation chamber outlet 3. After multiple detonation units are connected, a situation of end-to-end connection is formed. One of the detonation units is equipped with a starting detonating device 6, and the starting detonating device 6 of the inner ring and the starting detonating device 6 of the outer ring are symmetrical about the central axis of the ring where the multi-tube annular combustion chamber is located. The detonable mixture flows into the detonation chamber 2 along the direction perpendicular to the entrance 1 of the detonation chamber. When the detonation chamber entrance 1 of all detonation units has the detonable mixture filling the entire detonation chamber 2 under the same conditions, both Two starting detonation devices 6 work at the same time to form detonation waves propagating downstream in their respective detonation chambers 2. After the detonation waves propagate to the jet propagation pipe 8, most of the detonation waves are discharged through the detonation chamber outlet 3, and part of the detonation waves pass through the jet. The propagating pipe 8 propagates into the detonation chamber 2 of the next detonation unit, and quickly forms a detonation wave, so that the inner and outer circles of the combustion chamber are respectively transmitted, and the detonation wave propagates to the detonation jet outlet of the last detonation unit of the inner and outer circles respectively After 5, it returns to the detonation unit equipped with the detonation device 6, and the detonation unit equipped with the detonation device 6 has completed the exhaust gas discharge and the filling process of the detonable mixture, and the detonation jet is introduced into the detonation unit of the unit. After the shock chamber 2, a detonation wave is formed rapidly, and the detonation device 6 is started to no longer work. Thereafter, the combustion chamber enters a steady cycle, eliminating the need for external ignition equipment.

Device Embodiment 3: Referring to Fig. 5, it includes 12 detonation units connected back and forth through the jet propagation pipe 8 to form a ring-shaped multi-tube pulse detonation combustion chamber, the combustion chamber is installed on a rotating shaft 9, Can be rotated, the detonation unit includes a detonation chamber inlet 1, a detonation chamber 2, a detonation chamber outlet 3 and a jet propagation pipe 8, and the jet propagation pipe 8 includes the detonation jet outlet 5 and The detonation jet inlet 4 of the next detonation unit, the detonation chamber inlet 1 and the detonation chamber outlet 3 are located at both ends of the detonation chamber 2, the detonation chamber inlet 1 is at the most upstream, and the detonation jet inlet 4 is close to and located in the detonation chamber Downstream of the inlet 1, the detonation jet outlet 5 is close to and located upstream of the outlet 3 of the detonation chamber. After connecting multiple detonation units, a situation of end-to-end connection is formed. A starting detonation device 6 is installed on every detonation unit separated by 3 detonation units, that is, a total of 3 starting detonation devices 6 are installed and evenly distributed on the ring where the multi-tube pulse detonation combustion chamber is located. The detonable mixture flows into the detonation chamber 2 along the direction perpendicular to the entrance 1 of the detonation chamber. When the detonation chamber entrance 1 of all detonation units has the detonable mixture filling the entire detonation chamber 2 under the same conditions, three Two starting detonation devices 6 work at the same time, respectively forming detonation waves propagating downstream in their respective detonation chambers 2. After the detonation waves propagate to the jet propagation pipe 8, most of the detonation waves are discharged through the detonation chamber outlet 3, and part of the detonation waves pass through. The jet propagating pipe 8 propagates into the detonation chamber 2 of the next detonation unit, and rapidly forms a detonation wave, which is continuously transmitted. The detonation unit has completed the exhaust gas discharge and the filling process of the detonable mixture. After the detonation jet enters the detonation chamber 2 of the unit, a detonation wave is formed rapidly, and the detonation device 6 is no longer working. This creates a situation where the three detonation waves are chasing each other, after which the combustion chamber enters a steady cycle, eliminating the need for external ignition equipment.

Claims (8)

1, a kind of multi-pipe impulse detonation combustor, comprise many cover pinkings unit, each unit comprises detonation chamber inlet, the jet inlet that detonates, detonation chamber, the jet exit that detonates, detonation chamber outlet and starts priming device, it is characterized in that: detonation chamber inlet and detonation chamber outlet are positioned at the detonation chamber two ends, detonation chamber inlet is in upstream, detonate jet inlet near and be positioned at detonation chamber inlet downstream, detonate jet exit near and be positioned at detonation chamber outlet upstream; The jet inlet that detonates of the adjacent pinking with the next one of the jet exit that detonates unit links to each other, after a plurality of pinkings unit connects, the jet inlet that detonates of the detonate jet exit and the initial pinking unit of last pinking unit is connected, join end to end, constituted the multitube annular-shaped combustor of a plurality of detonation chamber inlets and the outlet of a plurality of detonation chamber jointly; The jet exit that detonates that links together has constituted jet jointly with the jet inlet that detonates and has propagated pipe; Starting priming device is installed on the detonation chamber of at least one pinking unit.

2, according to utilizing the described a kind of multi-pipe impulse detonation combustor of claim 1, it is characterized in that:, the startup priming device is installed all on N pinking unit of M-1 the pinking unit that be separated by when the number of one group of pinking unit during for N times of certain integer M.

3, according to utilizing the described a kind of multi-pipe impulse detonation combustor of claim 1, it is characterized in that: in radial arrangement multi-turn multitube annular-shaped combustor of multitube annular-shaped combustor, make its coaxial parallel connection, it is identical that the startup priming device quantity that starts priming device and every circle is installed at least one pinking unit of every circle, and the startup priming device of each circle circumferentially evenly distributes.

4, according to utilizing the described a kind of multi-pipe impulse detonation combustor of claim 1, it is characterized in that:, the startup valve is installed at the jet inlet place of detonating that the pinking unit that starts priming device is housed.

5, according to utilizing the described a kind of multi-pipe impulse detonation combustor of claim 1, it is characterized in that: described multitube annular-shaped combustor is installed on the running shaft, and the turning axle of multitube annular-shaped combustor self overlaps with running shaft.

6, a kind of method of initiation of utilizing the described device of claim 1 is characterized in that: when the detonation chamber of all pinking unit inlet all has when can quick-fried mixed gas being full of whole detonation chamber with identical condition, start priming device work.

7, according to utilizing the described method of initiation of claim 6, it is characterized in that: when the number of one group of pinking unit for the N of certain integer M doubly and when the startup priming device all was installed on N the pinking unit of M-1 the pinking unit that be separated by, this N startup priming device simultaneously detonated.

8, according to utilizing the described method of initiation of claim 6, it is characterized in that: when the detonation chamber of all pinking unit inlet all has when can quick-fried mixed gas being full of whole detonation chamber with identical condition, close the startup valve, start priming device work; After forming detonation wave in the startup valve downstream detonation chamber, start valve opening, and when the proper functioning of firing chamber, keep normally open always.

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