US2217694A - Method and apparatus for charging elongated explosion chamber - Google Patents

Description

Oct. 15 1940. i U, ME|N|NGHAU5 2,217,694

METHOD AND APPARATUS FOR CHARGING ELONGATED EXPLOSION CHAMBER Filed Marcha, 193s 2 sheets-sheet `1 ATTORNEYS Oct. 15 1940. u. MEININGHAUS METHOD AND APPARATUS FOR CHARC-ING ELONGATED EXPLOSION CHAMBER Filed llarch 3, 1938 2 Shasta-Sheet 2 w E N R O T T A Patented Oct. '15, 1940 UNITED STATES PATENT yori-lcs METHOD AND APPARATUS FOR CHARGING. ELONGATED EXPLOSION CHAMBER Application March 3, 1938, Serial No. 193,611 In Germany March 8, 1937 13Claims.

The present invention relates to explosion chambers, and particularly to explosion chambers of the constant volume type.

It is the general object of the invention to provide an improved method and apparatus for distributing uniformly a charge of fuel within the chamber, especially in a chamber of elongated form.

The present invention presents a. highly satis- IJ factory method of introducing fuel into an elongated explosion chamber whereby a uniform distribution of the fuel is attained in a supercharging or closed charging process in spite of the inertia and resistance of the body of air in the l5 chamber. In such supercharging or closed charging process, as is known, the residual combustion gases, following the discharge of the high pressure explosion gases, are expelled by scavenging air of comparatively low pressure, resulting in a considerable saving in compression work. The outlet member of the explosion chamber is then closed and the fuel alone, or together with a quantity of high pressure air, the socalled charging air, is introduced into the closed chamber. It is a peculiarity of this closed charging" process that conditions exist which make it dimcult or even impossible to obtain uniform lling of the interior of the chamber with the fuel-air mixture by known procedures, primarily because the scavenging air filling the chamber cannot escape since the outlet member is closed. The gaseous piston formed of the fuel or oi' the air carrier for the latter strikes rather against the relatively stagnant body of air in the compresses it toward the outlet end 0f the chamber. There cannot, therefore, take place any considerable mixing between the fuel and the air filling the chamber, so that the individual fuel particles do not become surrounded with the oxygen necessary for full, rapid and complete combustion. Y

'Ihe method of charging elongated explosion chambers, especially those employed with comit, bustion turbines, which is proposed in accordance with the present invention for the solution of the above mentioned problem, the charging being eiected with gaseous fuel or'fuel-laden gases, is characterized by the feature that the fuel is conducted through the chamber by means of currents developed along the walls ofthe chamber, advantageously with production of whirls rotating transversely to the longitudinal axis of the chamber and acting to break up the fuel stream,

53 said currents being only at one side of a plane .1 chamber, drives such air rst before it and finally containing the longitudinal axis of the chamber,

or of a plane parallel thereto but intersecting the interior of the chamber. By this mode of introduction of the fuel, the displacing (scavenging) air lling the chamber is first of all given the 5 opportunity to move to one side, so that the advance of the fuel in the direction from the inlet to the outlet members of the chamber is made possible. The one-sided introduction of the fuel has moreover the further effect that the masses l" of air lying in the vicinity of the fuel inlet member are likewise accelerated unilaterally and set into motion, so that in the region of the place oi' admission of the fuel, a cylindrical whirl is formed whose axis is approximately transverse l5, to the longitudinal axis of the chamber and which consequently distributes the fuel over the whole chamber cross-section and causes mixing of the fuel with air. As the asymmetrically traveling fuel stream advances in the direction of the outlet 2c members of the explosion chamber, further bodies of air more and more remote from the point of admission of the fuel become accelerated and are pushed aside, so that the formation of the cylindrical whirls continues, the fuel dis- 25 tribution transversely of the longitudinal axis of the chamber and the mixing of the fuel with the air being thus insured. In this way there is finally formed a whirl of this kind also in the parts immediately in advance of the outlet mem- 3H bers of the chamber, so that here also the required distribution and mixing of the fuel in and with the air takes place; it thus becomes only a question of time and also of the admission velocity of the fuel for even chambers of extremely large axial extent to be iilled in this way with a fuel-air mixture which is uniformly distributed throughout its interior.

The accompanying drawings show by way of example several constructions of explosion chambers for carrying out the charging process in accordance with the invention, the fuel employed by way of illustration being combustible furnace gases, such as blast furnace gases. Referring to the drawings:

Fig. 1 shows a vertical longitudinal section through an explosion turbine with two explosion chambers, only one, which is likewise in longitudinal section, along the line I--I of Fig. 2 being shown;

Fig. 2 represents a horizontal cross section through the explosion chamber of Fig. 1 at the level of the fuel inlet members and along the line II-II of Fig. 1;

Figs. 3 and i show different forms of fuel inlet sa dit devices and may represent the other inlet-devices of the arrangement shown in Fig. i;

Figs. 5, 6 and 'l show an explosion chamber provided with the inlet mechanism shown in Fig. 4, the several ilgures illustrating the charging conditions at different moments.

In the general view shown in Fig. 1, the nu=l meral i represents the scavenging air valve, 2 the fuel gas inlet valve, 3 the supercharging air valve, d the conical inlet end o the explosion chamber, 5 the cylindrical central portion of the chamber provided with igniting devices while i indicates the outlet end portion of the explosion chamber, t the nozzle or outlet valve, the nozzles, i@ the blades of the rotors il, i2 the stator blades, it the discharge pipe for the exhausted combustion gases, and it the outlet valve through which the residual combustion gases are withdrawn for further use. The elements so far described are known parts of an explosion chamber of the constant volume type.

In the operation of the explosion chamber, the residue of combustion gases in the explosion chamber d, 5, after the maiorportion of the gases has been discharged through the open valve 8 and has impinged the turbine rotors il, is expelled through the outlet valve ifi by the scavenging or displacing air which is brought into action upon opening of the scavenging air valve l. After the scavenging oi the chamber o these residual combustion gases, the valves l and ll are closed, the valve t being already closed, and the valves 2 and 3 are opened to introduce a gaseous fuel or a uelgladen gas, such as blast furnace gases,`into the explosion chamber in aci dition to a small duantity of supercharging air of higher pressure than the scavenging air; after the formation of a unitary mixture uniformly lling the explosion chamber, the spark plugs t ignite the so-formed explosive charge. Thereupon the nozzle valve 8 is opened and the gases expand out of the chamber and through the nozzle S and strike the rotor blades i. As soon as the pressure in the chamber has fallen to approximately the pressure oi the scavenging air, or slightly below the pressure of the latter, the outlet valve is is opened, followed by the opening oi the scavenging air 'valve fi, and the cycle is repeated.

In accordance with the invention, the fuel is directed into the explosion chamber in such a manner that it :dows along the chamber wall to one side of a plane which intersects the chamber and contains the longitudinal anis o the chamber or is parallel thereto. To accomplish this, the stream of fuel can be directed along a wall or portion of the wall of the chamber from a point of admission on the opposite eide oi the chamber, the fuel thus initially passing transverseiy through the inlet portion of the chamI ber; or the fuel stream may be directed 'ironiedlately along the portion oi the chamber well contiguous to the piace o admhsicn, being in. each case-directed toward the outlet end of the iainber; or e combination or both modes o fuel admission may he used.

Tous the roel may be conducted the chamber by means of currents developed alone the chamber walls immeatelv the reculent of contact with the latter alone one side oi o plane containing the longttudinal o the chamber or oi a plane parallel thereto, while the fuel introduced into the c' amber at the op" positely lying side is first driven at au anule to the longitudinal axis thereof, transversely astuces through the chamber, w the point oi contact with the chamber. The fuel stream along the chamber wall is thus combined from fuel currents developed along the chamber wall imme diately from the moment of introduction into the chamber and from fuel currents developed only from the moment of contact with the chamber wall on, and after passing transversely through the inlet portion of the chamber at an angle to the longitudinal axis of the same to the place of Contact with the chamber wall.

Fig. 1 shows an arrangement wherein the fuel is directed across the conical inlet end of the chamber obliquely to the longitudinal axis oil the chamber into contact with the opposite wall for unilateral ow therealong. The box or basket i5 of vthe fuel gas inlet valve 2 is completely closed except for the bore or bores i5 in the inner wall of the box. The axis of the bores cuts the longitudinal axis of the explosion chamber at an angle and strikes the opposite wall of the explosion chamber approximately at the level of the transition between the conical inlet end d of the chamber and the main cylindrical portieri 5 thereof. Upon opening of the inlet valve 2, the fuel is, therefore, introduced at an angle to the longitudinal axis of the explosion chamber and transversely through the chamber until it strikes the opposite chamber wall and there takes the form of a current ilowing substantially along the wall of the chamber. In the range of this current, which is developed alo/ng the chamber wall, the fuel is conducted through the chamber only at one side of a plane which contains the longitudinal axis of the chamber, or oi' a plane parallel thereto and intersecting the 'explosion chamber interior.

By such unilateral introduction of the fuel, the scavenging or displacing air, which at such time fills the interior of the explosion chamber, is displaced toward the left chamber wall in Fig. l, as the illustrated one-sided fuel current proceeds. In consequence, circular whirls must form, their axes lying approximately vertical to the plane of the drawing. These circular whirls distribute the fuel over the whole chamber crosssection and in this way eect a completely uniform mixing of the fuel and air. Upon termination of the charging step, the explosion chamber is lled throughout its interior with a completely and uniformly distributed unitary fuel-air minture, so that at the moment of ignition, all conditions are satised for a complete and explosive combustion.

From what has been said above, it will be seen that the fuel gas inlet valve which alone is visible in the illustration of Fig. l sufces com pletely ln the illustrated apparatus to eiect the desired unilateral introduction oi. fuel. However, as it is in general desirable im arrange a number ei inlet members in order to avoidI the comparatively large ow cross-section oi a single inlet member and resulting bulhlness of parts, an arrangement such as `that shown in Fig. 2 is to be preferred. ln this construction, the left-hand inlet valve is constructed in the manner disclosed in l. This construction, however, cannot be employed for the two other inlet valves, as in auch cese no oneeided new along the walls ci the combustion chamber would arise. The two other inlet valv are rather to be constructed according to the principles shown in figs. 3 or d, or according to both. Fig. 3 shows that the fuel gas inlet valve 2 again is provided with a closed valve boa or basket il, ivhcee viali is pro vided with a slit-like cutout, shown at IS, dlrected toward the outlet members 8, Ii ofA the explosion chamber. In order to bring this slitlike cutout into lproper action, the inlet cone 4 of the explosion chamber is recessed as shown at i9. If the left-hand inlet member 2 (Fig. `2) is constructed according to the proposals of Fig. l, 4

and if the two other valves are constructed as shown in Fig.' 3, then the fuel which was introduced transversely through the chamber by way of the bore i6 at an angle to the longitudinal axis of the chamber, and is guided from the area of contact with the opposite chamber wall and iiows along the latter, becomes combined with the fuel which was introduced upon this side by way of the slits I8 only along lthe chamber wall, so that the desired lateral ow along the chamber wall is accomplished.

Instead of constructing the guiding surfaces leading to this kind of fuel flow by means of bores I or cutouts i8, they can be formed with particular advantages according to Fig. 4, by means of domes or caps 2li which are arranged in front of the mouths 2l of the inlet valve boxes 22 upon the interior of the explosion chamber. These domes 20 arev closed exceptrfor the slits 23 which open toward the outlet members 8, Il'

of the explosion chamber, so that the fuel entering the explosion chamber through the slits 28 takes the form of a unilateral stream along the' explosion chamber wall from the moment of introduction. From this it will be seen that the additional inlet members which are shown in Fig. 2 can be constructed according to the pro posais 9of Fig. 4, so vthat they are so illustrated in Fig. 2.

In Figs. 5 to 7 are shown the different progressive conditions of the charging process; from the same figures can be seen the formation oi the circular whirls and likewise the advance of the latter from the place of introduction to the outlet end of the explosion chamber. 'I'he latter is constructed in the manner shown in Fig. 4.

At the beginning of the fuel introduction, there is first formed a circular whirl in the neighborhood of the place ci introduction of the fuel, as shown in Fig. 5. Even if the masses of air located in the explosion chamber at ilrst offer resistance to the introduced iuel and deilect the latter, with time particles of air lying progressively more remote from the place of introduction oi the fuel are set into motion, so that the deiiection of the introduced fuel stream occurs at points continuously more and more remote from the place of introduction. The fuel-distributing Whirl, therefore, travels according to Fig. 6, a1- ways further from the place of introduction, while the circular whirls produced in the neighborhood of the place of introduction do not disappear. Finally, by reason of the travel of the circular whirls and by the formation of constantly new whirls, there is created at the end of the charging process the condition shown in Fig. 7, which is also illustrated in Fis. 1. From a comparison of Figs. l and 7, it will be seen that for the formation of similar circular whirls, the place o introduction of the fuel, in the construction according to Fig. l, must lie upon the other side oi the longitudinal axis of the explosion chamber from that of constructions according to Figs. 4 and 7. There is thus aorded the possibility, as shown in Fig. 2, of arranging the inlet valves symn metrically to the longitudinal axis of the chamber, and in spite thereof, to secure a unilateral introduction of the fuel in accordance with the aaraeec principles of the invention. In this connection, it is entirely immaterial whether the inlet members are constructed one-half according to Fig. l and one-half according to Figs. 3 and 7, or Whether in the case of an uneven number of inlet members, as is shown for example in Fig. 2, the Vsmaller number of inlet members is constructed-according to Fig. l and the larger number according to Figs. 3 to "I, or whether, finally, the disposition is exactly reversed, as thereby nothing is altered so far as the result is concerned, that is, so far as relates to the unilateral guiding of the fuel stream along the explosion chamber walls.

I claim:

1. The method of charging elongated explosion chambers with gaseous fuel or with a fuel-laden gas, comprising directing the gaseous material through the chamber while the latter is filled withl a relatively stagnant body of air, along the wall of the chamberand only at one side of a, plane containing the longitudinal axis of the chamber or of a plane parallel thereto and intersecting the chamber interior, thereby throwing the air into whirls rotating transversely to thesaid longitudinal axis of the chamber and acting to break up the fuel stream by Way of currents developed 'by the 'fuel stream along the chamber Wall.

2. 'Ihe method according to claim 1, characterized by the fact that the gaseous material is conducted through the chamber to one side of a plane containing the longitudinal axis of the chamber or of a pla'ne parallel thereto and intersecting the chamber interior, in the Vform of currents developed along the chamber wall from substantially the moment of introduction of the gaseous material into the chamber.

3. The method according to claim 1, charac- -terized by the fact that the gaseous material is conducted through the chamber to one side of a plane containing the longitudinal axis of the chamber or of a plane parallel thereto and intersectingthe chamber interior, in the form of currents developed along the chamber wall from substantially the moment of contact of such gaseous material with the chamber wall, said material being first introduced into the chamber from the oppositely lying side and being directed at an angle to the longitudinal axis of the chambei' transversely through the chamber to the point of contact with the chamber wall.

4. The method according to claim l, characterized by the fact that the gaseous fuel-material is conducted through the chamber to one side of a plane containingthe longitudinal axis of theV chamber or of a plane parallel thereto and intersecting the chamber interior, in the form of currents developed along the chamber wall from substantially the moment of contact of said material with the chamber wall, the fuel currents in the chamber being composed of fuel streams developed from the moment of introduction into the chamber and from streams developed along the chamber wall only from the moment of contact with the latter, the latter fuel streams being introduced yinto the chamber from the opposite side and being directed at an angle to the longitudinal axis of the chamber transversely through for introducing the gaseous material into the chamber, and guiding surfaces arranged in the path of said material for causing the fuel to be conducted through the chamber in the form of currents developed along the chamber wall only at one side of a plane containing the longitudinal axis of the `chamber or of a plane parallel thereto and intersecting the chamber interior.

6. Apparatus according to claim 5, wherein the fuel introducing means comprises a plurality of fuel inlet members, and wherein the guiding surfaces are formed of caps which are arranged in the interior of the chamber in front' of the mouths of the fuel inlet members and are constructed in the form of a hood each having a discharge slit directed toward the outlet. members of the explosion chamber but being otherwise completely closed.

7. Apparatus according to claim 5, characterized by the fact that the fuel inlet members include valve;L chambers having cutouts whose walls provide the said guiding surfaces, said cutouts opening toward the outlet'end of the explosion chamber, and said valve chambers being closed except for said cutouts.

8. Apparatus according to claim 5, wherein the inlet portion of the chamber is conical, While the central portion is cylindrical, the fuel inlet members including valve chambers having bores whose walls provide the said guiding surfaces, said chambers being otherwise closed, the central axis of said bores being inclined at an angle to the longitudinal axis of the explosion chamber and intersecting the opposite chamber Wall approximately at the level of the transition between the inlet cone and the cylindrical part of the explosion chamber.

9. Apparatus according to claim 5, wherein the fuel introducing means comprises a plurality of fuel inlet members, certain of said members having valve chambers provided with cutouts and others being provided with caps having slits, said cutouts and slits being directed along Vthe chamber wall and toward the outlet end of the explosion chamber.

10. The method of charging elongated explosion chambers having fuel and air inlet members at one end and outlet mechanism at the opposite end thereof, comprising charging into the otherwise closed explosion chamber, after a charge of air has been introduced thereinto, a stream of gaseous fuel or fuel-laden gas, along a limited portion of the wall of the explosion chamber to only one side of a plane passing through the longitudinal axis oi' the chamber and in the general direction of the outlet end thereof, so aS thereby to set the body of air into whirling movement progressively as the fuel stream travels toward said chamber outlet and thus distribute the fuel across and throughout the interior of the chamber.

11. The method of charging elongated explosion chambers having fuel and air inlet members at one end and outlet mechanism at the opposite end thereof, which comprises directing a plurality of streams of gaseous fuel or fuelladen gas along a portion of the chamber wall lying to one side of a plane passing through the longitudinal axis of the chamber and in the direction of the outlet end of the chamber, so as thereby to cause the formation of whirls of fuel rotating about axes transverse to the longitudinal axis of the chamber and thus distributing the fuel across and throughout the interior of the chamber.

12. The process according to claim 11, wherein the fuel is introduced into the chamber at a plurality of points distributed about the circumference of the chamber at the inlet end thereof, one or more of the fuel streams being directed immediately along the adjacent chamber wall from the point-of introduction, while one or more of the fuel streams are projected transversely through the chamber from the opposite wall and join the other streams along the said adjacent chamber wall, all to one side of a plane passing through the central longitudinal axis of the chamber or of a plane parallel thereto and intersecting the interior of the chamber.

13. Apparatus for uniformly distributing a charge of gaseous fuel or fuel-laden air within an elongated explosion chamber filled with a relatively stagnant body of air comprising a plurality of inlet members arranged about the inlet end section of the explosion chamber and located at opposite sides of a plane parallel to the longitudinal axis of the chamber and intersecting the interior of the chamber, the inlet member or members at one side of such plane being constructed to direct the gaseous material along the contiguous chamber wall and in the direction of the outlet end of the chamber, and the inlet member or members arranged upon the opposite side of said plane being provided with discharge openings which direct the gaseous material transversely through the inlet section of the chamber and against the said contiguous wall, whereby the streams of gaseous material are united along such wall and move along such wall in the direction of the outlet end of the chamber while setting portions of the body of air in the chamber progressively more distant from the inlet end of the chamber into motion, whereby the fuel is distributed transversely of the chamber.

ULRICH MEININGH'AUS.

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