Mobile blast simulator

Abstract

A device that simulates the sound and pressure characteristics of gunfire by combusting combustible fluid and facilitating a deflagration-to-detonation transition of that combustion. The device includes a manifold for receiving combustible fluids, or precursors thereof, and preparing quantities of it for combustion. The device also includes a combustion component that receives said quantities and combusts it in an elongated chamber. Also disclosed are types of obstacles that can create turbulence in a flame front to facilitate a deflagration-to-detonation transition.

Description

MOBILE BLAST SIMULATORCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a nonprovisional patent application under the Patent Cooperation Treaty, based on claiming priority to U.S. Provisional Application No. 63 / 526,356, filed on July 12, 2023, which is incorporated by reference as if fully recited herein.FIELD

[0002] The application relates to gunfire and explosion simulation devices and, more particularly, to devices that simulate gunfire and explosions by combusting quantities of combustible fluid and transitioning that combustion from a deflagration-type of combustion to a detonation-type of combustion.BACKGROUND

[0003] Training military and law enforcement personnel to effectively respond to dynamic and hazardous situations is crucial. Traditional training methods often involve live fire exercises or the use of blank rounds to simulate gunfire and explosives, which carry inherent risks and logistical challenges.

[0004] Active shooter training is commonly employed to train police officers, military personnel, and private citizens on how to respond in the event there is an active shooter. By undergoing such training, a trainee may learn how to remain composed in the presence of gunfire while also improving his / her ability to react quickly and appropriately. The effectiveness of active shoot training depends, at least in part, on the realism of the training methods. Towards this end, some training methods may incorporate the use of live rounds. However, in many cases it is often impractical or otherwise dangerous to do so, such as when training indoors or in close proximity. For this reason, devices / systems / methods for simulating gunfire often finds utility.

[0005] There currently exist several different methods of simulating gunfire. For example, gunshot sounds may be amplified with speakers (e.g., a PA system) or replicated by firing simulation / blank rounds, firing paintball guns, popping balloons, clapping pieces of wood together, and the like. In any case, these methods often leave much to be desired due to being dangerous (e.g., excessive decibel levels causing hearing loss without protection, residual damage to facilities / surroundings, etc.), not realistic (e.g., failure to elevate adrenaline levels and heart rates, lack of percussion or shockwave force, etc.), or otherwise unsuitable (e.g., extensive setup time, consumable costs, etc.). Additionally, these traditional methods often fail to accurately mimic the true chaos and variability of live combat scenarios, thus limiting the realism of the training.

[0006] Accordingly, those skilled in the art continue with research and development efforts in the field of gunfire simulation devices.SUMMARY OF THE INVENTION

[0007] Disclosed are devices for simulate gunfire and / or explosions.

[0008] In one embodiment, the device includes a manifold that includes a first rail, a first injector unit, a second injector unit, and second rail. The first rail defines a first channel for receiving fuel from a fuel source and a second channel for receiving oxidizer from an oxidizer source. The first injector unit includes a conduit in fluid communication with the first channel of the first rail and a valve configured to control flow of fuel through the conduit of the first injector unit. The second injector unit includes a conduit in fluid communication with the second channel of the first rail and a valve configured to control the flow of oxidizer through the conduit of the second injector unit. The second rail defines a channel, wherein the channel of the second rail is in fluid communication with the first injector unit and is configured to receive fuel therefrom. The channel of the second rail is also in fluid communication with the second injector and is configured to receive oxidizer therefrom. Upon being received in the channel of the second rail, the fuel and oxidizer mixes to yield combustible fluid. The device further includes a combustion component. The combustion component includes a barrel component that defines an internal cavity and a combustion chamber. The internal cavity is in fluid communication with the channel of the second rail and is configured to receive combustible fluid therefrom. The combustion chamber includes a first end in fluid communication with the internal cavity and an opposing open second end. A unidirectional flow path is defined from the channel of the second rail, through the internal cavity, to the open second end of the combustion chamber. The combustion chamber also includes a spark plug proximate the internal cavity of the barrel component that is configured to generate a spark therein. Thecombustion chamber further includes at least one of obstacle downstream of the internal cavity. With this device, ignition of combustible fluid in the internal cavity results in a deflagration-type of combustion involving a flame that propagates away from the internal cavity and travels through the combustion chamber. Moreover, the at least one obstacle creates sufficient turbulence in propagating flame fronts so as to cause a transition from a deflagration-type of combustion to a detonation-type of combustion, thereby generating sound and pressure.

[0009] In another embodiment, the device further includes a fuel source and an oxidizer source. The fuel source may include at least one of: methylacetylene-propadiene propane, propane, and acetylene. The oxidizer source may include at least one of: nitrous oxide, oxygen, and air.

[0010] In another embodiment, the device further includes at least one pressure sensor configured to determine the output pressure from the fuel source and the oxidizer source. The device also includes a processor in communication with the pressure sensor and the valves of the first and second injector units. The processor is configured to adjust the amount of time the valves of the first and second injector units are opened in order to adjust for changes in output pressure from either the fuel source or the oxidizer source.

[0011] In another embodiment, the manifold is configured to output fuel and oxidizer at a ratio in the range of about 1 :8 to about 1 :10, and more preferably at a ratio of about 1 :9.

[0012] In another embodiment, the at least one obstacle includes a plurality of structural elements that extends into the interior of the combustion chamber. The plurality of structural elements may be provided in the form an insert that is insertable in thecombustion chamber, wherein the insert defines an open interior with the plurality of structural elements extending into the open interior. The insert may also define a plurality of straight-line channels through its open interior. The insert may be positioned next to the internal cavity.

[0013] Other examples of the disclosed device will become apparent from the following detailed description, the accompanying drawings and the appended claims.BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1 is a front perspective view of a first embodiment of a mobile blast simulator (MBS);

[0015] FIG. 2 is a front perspective view of the MBS of Fig. 1 without the housing;

[0016] FIG. 3 is a front perspective view of the MBS of Fig. 1 without the shroud;

[0017] FIG. 4 is a front perspective view of the MBS of Fig. 1 without support framing;

[0018] FIG. 5 is a front perspective view of support framing of the MBS of Fig. 1 ;

[0019] FIG. 6 is a right-side perspective view of the manifold of the MBS of Fig. 1 ;

[0020] FIG. 7 is a bottom perspective view of the manifold of the MBS of Fig. 1 ;

[0021] FIG. 8 is a right-side cross-sectional view of the first rail of the manifold of the MBS of Fig. 1 ;

[0022] FIG. 9 is a left-side cross-sectional view of the second rail of the manifold of the MBS of Fig. 1 ;

[0023] FIG. 10 is a left-side perspective view of the second rail of the manifold of the MBS of Fig. 1 ;

[0024] FIG. 11 is a front perspective view of the combustion component of the MBS of Fig. 1 ;

[0025] FIG. 12 is a front cross-sectional view of the combustion component of the MBS of Fig. 1 ;

[0026] FIG. 13 is a side perspective view of an embodiment of an insert;

[0027] FIG. 14 is a side view of the insert of Fig. 13; and

[0028] FIG. 15 is a perspective view of a second embodiment of an MBS.DETAILED DESCRIPTION

[0029] The following detailed description refers to the accompanying drawings, which illustrate specific examples described by the disclosure. Other examples having different structures and operations do not depart from the scope of the present disclosure. Like reference numerals may refer to the same feature, element, or component in the different drawings.

[0030] Illustrative, non-exhaustive examples, which may be, but are not necessarily, claimed, of the subject matter according the present disclosure are provided below. Reference herein to “example” means that one or more feature, structure, element, component, characteristic and / or operational step described in connection with the example is included in at least one embodiment and / or implementation of the subject matter according to the present disclosure. Thus, the phrase “an example” and similar language throughout the present disclosure may, but do not necessarily, refer to the sameexample. Further, the subject matter characterizing any one example may, but does not necessarily, include the subject matter characterizing any other example.

[0031] The present invention generally relates devices for replicating the noise and pressure characteristics of various firearms. Such devices are useful for creating realistic simulations of gunfire which may be desirable for purposes such as military or police training, emergency response training, recreation, and the like. Such devices are referred to throughout this disclosure as “mobile blast simulators” (MBS).

[0032] Embodiments of the invention are discussed below with reference to FIGS. 1 -15. However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes, as the invention extends beyond these limited embodiments.

[0033] Figs. 1-4 show an exemplary embodiment of an MBS 100 in accordance with the present invention. MBS 100 replicates the noise and pressure characteristics of firearms by enabling the rapid and repeated combustion of quantities of combustible fluid (referred to as a “charge” or “charges”) and facilitating a deflagration-to-detonation transition (DDT) of that combustion to ultimately produce sound and pressure.

[0034] As used herein, the term “fluid” can refer to substances of either the liquid or gasses phase.

[0035] Deflagration is a type of combustion involving a flame front that propagates at subsonic speeds through a charge with the flame sustaining itself by way of its own heat release. Detonation is a type of combustion involving a supersonic exothermic front accelerating through a medium that eventually drives a shock front propagating directly in front of it. The main mechanism of detonation propagation is a powerful pressure wavethat compresses the unburnt gas ahead of the wave to a temperature above the autoignition temperature. DDT occurs when a subsonic flame front accelerates to supersonic speed. When that happens, the flame goes from being sustained by a deflagration type of combustion to a detonation type of combustion. DDT occurs under certain conditions, mainly due to geometrical conditions such as partial confinement and the presence of obstacles in the flame path that cause turbulent flame eddy currents.

[0036] Referring to Fig. 4, cannisters 30 and 32 are fluid sources that each hold a quantity of combustible fluid or combustible fluid precursor. Cannisters 30 and 32 can be fluidly connected to manifold 40 using suitable conduits (hoses, tubes, etc.) (not shown) in order to transfer their respective fluids to it. Manifold 40 provides a means for controlling the preparation of charges using said fluids and directs the charges to combustion component 70. Combustion component 70, in turn, provides a means for combusting charges, facilitating DDT, and exhausting combustion byproduct (fumes, dust, odors, etc.).

[0037] Cannisters may be put into or removed from MBS 100 by opening its housing (consisting of tub 10 and lid 12) (Fig. 1) and lifting shroud 14 (Fig. 2), thereby accessing the areas where cannisters are held. This relatively simple process allows cannisters to be easily swapped out as needed.

[0038] It is contemplated that other embodiments of the MBS may be configured for either more than two or as few as a one cannister. It is also contemplated that other embodiments of the MBS may not utilize replaceable cannisters at all and may instead opt for a different type of vessel. For example, an embodiment of the MBS may include a dedicated fluid tank built into or fabricated as a part of its housing or another componentof the MBS. Variations such as these do not represent a departure from the scope of the present disclosure.

[0039] For the preparation of charges, it is preferable that the combustible fluid generally consist of a pre-mixture of gaseous fuel and oxidizer. Towards that end, MBS 100 may be equipped with a cannister of fuel and a cannister of oxidizer (discussed below, manifold 40 provides a way for fluid from two cannisters to mix, giving combustible fluid). Alternatively, if pre-mixtures of fuel and oxidizer are available in suitable cannisters, then both cannisters used in MBS 100 may be cannisters of pre-mixture. MBS 100 can be operated in either situation.

[0040] Through testing, it has been determined that the following gaseous fuel / oxidizer mixtures are suitable for use with MBS 100: MAPP and nitrous oxide, MAPP and oxygen (O2), propane and oxygen, acetylene and oxygen, propane and air, and acetylene and air. Of these mixtures, MAPP and nitrous oxide was the most preferred due to general availability and flame front speed. The ratio of fuel-to-oxidizer is preferably in the range of about 1 :8 to about 1 :10, with a ratio of about 1 :9 being the most preferred.

[0041] It is noted that “MAPP” is the commercial name for a methylacetylenepropadiene propane product available from BernzOmatic of Newark, New Jersey. A related product, MAP-Pro (model number MG9), also available from BernzOmatic, is a propylene-based gas product that has been found to be a suitable as well with MBS 100. MAP-Pro may be utilized as the fuel with nitrous oxide as the oxidizer.

[0042] It has further been determined through testing that manifold 40 of MBS 100 is able to tolerate equivalence ratios ranging from about 0.8 to about 1.01 , which is considered remarkably broad. The ability of manifold 40 to accommodate a wide varietyof fuels combined with a remarkable tolerance to wide equivalency ratios enables consistent detonations across a wide variety of operating conditions (e.g., hot and cold weather, high and low altitudes, and varying fill volumes).

[0043] Referring to Figs. 6-7, manifold 40 includes a first rail 42, a second rail 60, and five injector units 50 in fluid communication with the first rail 42 and the second rail 60. The first rail 42 is configured to receive fluid from cannisters 30, 32 and distribute that fluid to the injector units 50. Each injector unit includes a conduit 52 (Fig. 7) for transferring combustible fluid from the first rail 42 to the second rail 60 and a valve 54 (Fig. 6) which may be opened or closed to control the flow of fluid through their respective conduits. The second rail 60 receives fluid from the injector units 50 and directs it towards the combustion component 70.

[0044] Valves 54 of MBS 100 are two-way solenoid valves. Other embodiment of the MBS may utilize other types of valves in addition to or as an alternative for such valves without departing from the scope of the present disclosure.

[0045] Referring to Fig. 8, defined in the body of first rail 42 is channel 44 and channel 46, both of which extend horizontally along the length of the first rail 42. As can be seen in Figs. 6-7, channel 44 is plugged on one end and has a threaded socket incorporated in the other; channel 46 is also plugged and has a threaded socket but on the opposing sides of the first rail. The threaded sockets may be used to facilitate the coupling of conduits which, in turn, may be coupled to cannisters to supply channels 44 and 46 with fluid.

[0046] The body of the first rail 42 also defines openings extending into channels 44 and 66 that enable the first rail 42 to distribute fluid to the five injector units 50. In thisembodiment, there are four upper injector units in fluid communication with the channel 46 and a single lower injector unit in fluid communication with the channel 44. This design generally allows for a greater quantity of fluid to flow through channel 46 compared to channel 44. Other embodiments of the MBS may vary in the number of injector units provided for each channel without departing from the scope of the present disclosure; some may have as little as one injector unit for each.

[0047] Referring to Figs. 9-10, the body of the second rail 60 defines corresponding openings that enable the second rail 60 to receive fluid from the five injector units. Also defined in the body of the second rail is channel 62, channel 64, and channel 66. Channel 62 is relatively small and extends vertically; it enables the second rail to transfer fluid from the single lower injector unit to channel 66. Channel 64 extends generally horizontal and features opposing linear sections connected in the center by an annular section; it enables the second rail 60 to transfer fluid from the four upper injection units to channel 66. Channel 66 receives fluid from channels 62 and 64 and directs it upwards out of the second rail 60 through a top-side opening. In instances where two different types of fluid is used, channel 66 provides a space for the two fluids to begin mixing with one another.

[0048] In a preferred mode of using MBS 100, a conventional 640-gram size cannister of nitrous oxide may be fluidly connected to channel 46 of the first rail 42 and fed into the second rail 60 through the four upper injection units, and a 14.1 -ounce size cannister of MAPP may be fluidly connected to channel 44 of the first rail 42 and fed into the second rail 60 through the single lower injection unit. The nitrous oxide and the MAPP would then mix in channel 66 of the second rail 60 yielding combustible fluid suitable for use as a charge. The amount of MAPP relative to nitrous oxide, as well as the overallquantity of fluid in that charge, can be controlled through the coordination of the four upper injector units and the single lower injector unit (by selectively opening the valves thereof for various lengths of time).

[0049] It has been observed that the use of these two fuels with MBS 100 was able to frequencies of well over 60 hertz (i.e., number of combusted charges per second) and was operable with fill volumes as little as 100 milliliters (in combustion chamber 82, best shown in Fig. 12).

[0050] Referring to Figs. 11 -12, combustion component 70 includes riser 72, barrel component , and spark plug 88. Barrel component 78 includes connecting piece 74 and barrel extension 76. The body of connecting piece 74 defines: a) channel 80 which is downwardly angled in the vertical-to-horizontal dimension; and b) internal cavity 82 which channel 80 opens into. Channel 80 is connected to channel 66 of the second rail 60 via riser 72. Internal cavity 82, on the other hand, opens into the interior of barrel extension 76, which defines a combustion chamber 84. Combustible fluid may be fed into internal cavity 82 through riser 72 to fills combustion chamber 84. Notably, the cross-sectional area of internal cavity 82 is greater than the cross-sectional area of channel 80. The difference in cross-sectional area in combination with the downward angle of channel 80 may help to prevent backflow of combustible fluid from internal cavity 82 into riser 72.

[0051] Spark plug 88 is integrated into the connecting piece 74 proximate (i.e., at or near) internal cavity 82 and is used to generate a spark therein. MBS 100 utilizes a 19 mm nickel spark plug, but it is contemplated that spark plugs of other sizes and materials may be suitable as well. To activate spark plug 88, electricity may be supplied by battery 34 and stepped up in voltage to the necessary degree by ignition coil 90 (Fig. 4).

[0052] When in operation, combustible fluid from manifold 40 is transferred upwards through the riser 72 into the through connecting piece 74. This continues until combustion chamber 84 is filled to the desired level with combustible fluid. From there, spark plug 88 ignites the combustion fluid to cause combustion and creates a flame that propagates away from internal cavity 82. This flame continues through barrel extension 76 and, if enough combustible fluid is provided, out of its open end. Thus, there is a unidirectional flow path for combustion fluid, flame, and / or combustion byproduct that starts at channel 66 and ends at the open end of barrel extension 76.

[0053] Upon igniting the combustible fluid within internal cavity 82, the initial result is a deflagration-type combustion. This combustion must be transitioned to a detonationtype combustion in order to produce higher intensity sound and pressure which is characteristic of real gunfire. Towards that end, obstacles must be provided downstream of internal cavity 82 in the flow path. Without being bound by any particular theory, it is contemplated that the presence of obstacles in flame path creates turbulent flame eddy currents which accelerates, at least in some areas, the rate at which a flame front propagates. Provided that a suitable configuration of obstacles is present, this acceleration can be sufficient to accelerate a subsonic flame to supersonic speeds, resulting in DDT.

[0054] Shown in Figs. 13-14 is an exemplary embodiment of an insert 92 for introducing obstacles into the flow path described above. One or more copies of insert 92 may be installed in (i.e., inserted into) barrel extension 76 and / or the space 86 defined in connecting piece 74 just before it meets barrel extension 76. Multiple copies may be used if additional turbulence is desired. In any case, by this arrangement such insert(s)would be positioned downstream of internal cavity 82 and can thereby receive flame fronts as they propagate away from internal cavity 82.

[0055] Preferably, an insert would be provided in space 86, immediately next to internal cavity 82. This enables a propagating flame to accelerate early in the flow path and, in turn, for DDT to occur quicker. The resultant pressure wave can then compress the remaining combustible fluid in the combustion chamber 84 to propagate detonation.

[0056] Insert 92 features a generally cylindrical body that defines an open interior and has a plurality of interior linear struts 96 provided at various locations along its length. Insert 92 is preferably sized such that it closely corresponds with the inner wall of exhaust barrel 76 and / or connecting piece 74 at space 86 (it is noted that the cross-sectional shape and area of space 86 is generally the same as the cross-sectional shape and area of the interior of exhaust barrel 84). Linear struts 96 are structural elements that extend into the open interior of the insert 92 and can function as obstacles in the path of a flame. Notably, insert 92 also defines a plurality of straight-line channels 98 through its interior that do not obstruct the path of a flame (Fig. 14). For this and other embodiments of the insert, incorporating both design features - i.e., structural elements that extend into the open interior and straight-line channels through the interior - is preferred.

[0057] Other embodiments of the insert may vary with respect to the design of their structural elements (which extend into the open interior of the insert and function as obstacles). For example, the structural elements may not be entirely linear, and may instead be bent or curved. Further, the structural elements may not be diametric, and may instead extend across non-diametrically opposed points along the interior of the insert, including points that are not coplanar transverse to the major axis of the generallycylindrical insert. Still further, some of the structural elements may be connected to one another so as to form more complex obstacles within the interior of the insert. Variations such as these do not represent a departure from the scope of the present disclosure.

[0058] In other embodiments of the MBS, it is contemplated that rather than providing obstacles via an insert, which is a discrete component, obstacles may instead by fabricated as a part of connecting piece 74 and / or exhaust barrel 76.

[0059] Referring to Figs. 15, depicted is a second exemplary embodiment of an MBS 200 according to the present invention. In this figure, only the barrel extension 210 of the combustion component is realistically depicted. The illustrations of the manifold 220 and the other components are only meant to be conceptual representations. Notably, barrel extension 210 is much longer than barrel extension 76 of MBS 100 and features horizonal and vertical 180° bends. These bends are also capable of creating turbulence in propagating flame fronts and can facilitate DDT as well. Thus, curves or bends in the flow path downstream of where charges are ignited may also be considered “obstacles” for purposes of the present invention even though they are not structural elements that extend into the flow path. In embodiments of the MBS, such curves or bends may be used either in addition to or as an alternative for the obstacles described above.

[0060] Embodiments of the MBS, including MBS 100, may be equipped with any suitable configuration of power, computing, and networking components capable of supporting and enabling the functions described above (namely, the valves 54 of injector units 50 and spark plug 88). These components may include, for example, batteries, processors, memory, I / O modules, pressure sensors, temperature sensors, and transceivers for wireless communication with other devices (e.g., via Bluetooth or WiFi).

[0061] In exemplary embodiments, a remote controller may be provided that is in communication with an MBS and configured to initiate the preparation and combustion of charges. Preferably, the remote controller may be capable of two-way communication and would be able to show, for example, status levels, rates of fire, pressure monitoring, battery status, etc. on a display.

[0062] In exemplary embodiments, the MBS may be operatively connected to, and configured to receive input from, other training tools target systems via serial communication, hardwire connections (e.g., dry contact closure for trip wires / pressure plates, etc.), and voltage trigger sensing.

[0063] In exemplary embodiments, pressure sensors may be provided to measure the pressure within the cannisters. This may allow operators of the and MBS to determined when said cannisters are in need of replacement. Moreover, this may also allow operators to determine whether valves in certain injector units need to be opened for a longer amount of time, thereby allowing more of a certain fluid to be released, in order to compensate for a drop in pressure so that the desired ratio of fluids in a charge can be maintained. This type of adjustment may also be automated in some embodiments.

[0064] Referring to Figs. 3-5, MBS 100 further includes a support framing for mounting or otherwise mechanically supporting the various components of MBS 100 described above. Notably, dual handles provided on opposing sides of the support framing allow the entire support framing to be lifted out of the housing (Fig. 1 ).

Claims

CLAIMSWHAT IS CLAIMED IS:Claim 1 . A device for simulating gunfire comprising: a manifold comprising: a first rail that defines: a first channel for receiving fuel from a fuel source; and a second channel for receiving oxidizer from an oxidizer source; a first injector unit comprising: a conduit in fluid communication with the first channel of the first rail; and a valve configured to control flow of fuel through the conduit of the first injector unit; a second injector unit comprising: a conduit in fluid communication with the second channel of the first rail; and a valve configured to control the flow of oxidizer through the conduit of the second injector unit; a second rail that defines a channel, wherein: the channel of the second rail is in fluid communication with the first injector unit and is configured to receive fuel therefrom;the channel of the second rail is also in fluid communication with the second injector and is configured to receive oxidizer therefrom; and upon being received in the channel of the second rail, the fuel and oxidizer mixes to yield combustible fluid; a combustion component comprising: a barrel component that defines an internal cavity and a combustion chamber, wherein: the internal cavity is in fluid communication with the channel of the second rail and is configured to receive combustible fluid therefrom; the combustion chamber comprises a first end in fluid communication with the internal cavity and an opposing open second end; and a unidirectional flow path is defined from the channel of the second rail, through the internal cavity, to the open second end of the combustion chamber; a spark plug proximate the internal cavity of the barrel component that is configured to generate a spark therein; and at least one of obstacle downstream of the internal cavity; wherein ignition of combustible fluid in the internal cavity results in a deflagrationtype of combustion involving a flame that propagates away from the internal cavity and travels through the combustion chamber; andwherein the at least one obstacle creates sufficient turbulence in propagating flame fronts so as to cause a transition from a deflagration-type of combustion to a detonation-type of combustion, thereby generating sound and pressure.Claim 2. The device of claim 1 , further comprising a fuel source and an oxidizer source.Claim 3. The device of claim 2, further comprising: at least one pressure sensor configured to determine the output pressure from the fuel source and the oxidizer source; and a processor in communication with the pressure sensor and the valves of the first and second injector units; wherein the processor is configured to adjust the amount of time the valves of the first and second injector units are opened in order to adjust for changes in output pressure from either the fuel source or the oxidizer source.Claim 4. The device of claim 2, wherein: the fuel source comprises at least one of: methylacetylene-propadiene propane, propane, and acetylene; and the oxidizer source comprises at least one of: nitrous oxide, oxygen, and air.Claim 5. The device of any of the preceding claims, wherein the manifold is configured to output fuel and oxidizer at a ratio in the range of about 1 :8 to about 1 :10, and more preferably at a ratio of about 1 :9.Claim 6. The device of any of the preceding claims, wherein the at least one obstacle comprises a plurality of structural elements that extends into the interior of the combustion chamber.Claim 7. The device of claim 6, wherein the plurality of structural elements is provided in the form an insert that is insertable in the combustion chamber, the insert defining an open interior with the plurality of structural elements extending into the open interior.Claim 8. The device of claims 7, wherein the insert defines a plurality of straight- line channels through its open interior.Claim 9. The device of claims 7 or 8, wherein the insert is positioned next to the internal cavity.

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