Mixer for gaseous media and method for mixing gaseous media

p0001The invention relates to a mixer for gaseous media with a venturi tube through which in Rohrachsrichtung a gas flows and are provided in the region of narrowed cross-section at the pipe wall inlet openings for beizumischendes gas and a method of use of the mixer.

p0002In the operation of gas engines, the problem is that the composition of the supplied gases is subject to fluctuations. These variations are quite significant. Some operators of gas engines could significantly increase the efficiency of their plants if they provide standard two gas qualities, such as biogas and natural gas alternately or simultaneously for the operation. Another problem is that the gases contain undesirable impurities which cause deposits in the mixer. Such admixtures are, for example, sulfur and water.

p0003The object of the invention to provide a mixer which carries the variations of the compositions during the operation and shall be determined in which malfunctions avoided by contamination. Furthermore, the simultaneous or alternate use of different gas qualities to be made possible. This object is inventively achieved by a mixer for gaseous media according to claim 1. Preferred embodiments are subject of the dependent claims or are described below.

p0004Indicator of the mixer for gaseous media with a venturi tube through which in Rohrachsrichtung a gas flows and are provided in the region of narrowed cross-section at the pipe wall inlet openings for beizumischendes gas is that the inlet openings have a variable passage cross section, which while in operation the mixing process by means of control elements can be changed. The variability of the passage cross-sections for the product ready for incorporation gas during operation a constant fine-tuning of the gas admixture is achieved. This is a smooth running and an efficient use of energy is of great importance.

p0005It is envisaged that the passage cross-sections of the inlet openings rule specifications are in accordance with the operation during the mixing process by means of the control elements is continuously variable. With the continuous adjustment of the mixer can react sensitively and rapidly to changes in the composition / resources during operation.

p0006The portion of the Venturi tube of narrowed cross-section in which there are the inlet openings is of opposite the venturi-adjustable control elements, comprises means of adjustment in a the passage cross sections of the inlet openings are variable. The control elements at least part of one, the constricted cross-sectional comprehensive control sleeve, which is provided with fuel control orifices, when played adjusting the fuel control orifices and the inlet openings the size of the passage cross-sections can be changed.

p0007According to a further embodiment of the invention it is provided that the control sleeve is adjustable by means of a control mechanism.

p0008According to another embodiment of the invention provides that the control sleeve is connected to the control mechanism via a thrust strip which moves the control sleeve according to the specifications of the control mechanism, preferably a flexible and springy stiff thrust strip, whereby the flow cross-sections are changeable. The thrust strip preferably has a certain rigidity. He is supported on the outer housing wall. This has the advantage that the friction on the control sleeve remains virtually constant, not dependent on bias. A thermal expansion in the housing does not lead to an increase in friction in the control sleeve, but only has an influence on the angle of rotation of the control sleeve.

p0009According to a further embodiment of the invention it is provided that the thrust strip is attached to a reel of the governing mechanism on the one hand and on the control sleeve on the other hand, and in that the control sleeve to rotate on the narrowed cross-section of the Venturi tube in accordance with the Verstellvorgabe of the control mechanism of the roller over the thrust strip is.

p0010According to another embodiment of the invention provides that the control sleeve is connected to the control mechanism via a rigid connecting rod, which moves the control sleeve according to the specifications of the control mechanism and thus the passage cross-sections are changeable.

p0011According to a further embodiment of the invention it is provided that the rigid connecting rod is hinged to the transmission means of the control mechanism on the one hand and on the control sleeve on the other hand articulated, and that the control sleeve on the narrowed cross section of the Venturi tube in accordance with the Verstellvorgabe of the control mechanism by the transmission means via the thrust strip is rotated.

p0012According to another embodiment of the invention provides that the control sleeve is provided with a toothed ring, on the one accessible from the control mechanism pinion drives a timing belt, with the specifications of the control mechanism, the control sleeve is correspondingly rotated to the narrowed section of the venturi and so that the passage cross-sections are changeable.

p0013According to another embodiment of the invention provides that, for a multi-row arrangement of the inlet openings at the venturi the fuel control openings of the control sleeve are provided on both sides of the attack portion of the flexible until spring stiff thrust strip, the rigid connecting rod or ring gear.

p0014According to a further embodiment of the invention it is provided that a window is provided in the mixer housing through which the position of the actuators can be observed.

p0015According to a further embodiment of the invention it is provided that along the axis of the Venturi tube a gas displacement body, for example in the form of an airship, if necessary replaceable, is arranged. The interchangeability is used for rapid adjustment of the cross section of the constricted Venturi tube, with the adaptation to any operating conditions is achieved.

p0016The gas displacement body is preferably hollow on the side in the flow shadow and there comprises a corresponding outlet for the gas. Through the cavities for conducting gas an optimum gas mixture is achieved in the interior of the Venturi tube.

p0017According to another embodiment of the invention provides that at least are provided for beizumischendes gas two gas supplies. By (at least) two gas connections supplying various gases will be improved.

p0018The control sleeve must be as accurately seated on the Venturi tube; but it must not be difficult to move because of contamination or thermal expansion. According to a particular embodiment of the invention it is provided that the control sleeve is made of a dimensionally stable and self-lubricating material.

p0019According to a further embodiment of the invention it is provided that the form-retaining and self-lubricating material of the control sleeve contains stabilizers and lubricating components.

p0020According to a further embodiment of the invention it is provided that the material of the control sleeve is made of plastic, in particular of a self-lubricating equipped with a solid lubricant plastic. A suitable material is for example Murylat SP ® (PETP-SP).

p0021The working method used for mixing the gases operates with a mixer with a Venturi tube through which in Rohrachsrichtung a gas flows and in whose area of ​​narrowed cross-section through provided on the pipe wall inlet openings flows beizumischendes gas, the passage cross sections of the inlet openings can be varied to the composition of a mixed gas to be supplied to a load adapted to the needs.

p0022The passage cross-sections of the inlet openings are continuously changed during operation for the mixing operation according to need to continuously adjust the composition of a consumer supplied mixed gas needs.

p0023The invention will be explained in more detail with reference to the drawing. Show it:<ul><li><figref idrefs="f0001">Fig. 1</figref> containing a venturi tube a mixer for gaseous media, are provided in the region of narrowed cross-section at the pipe wall inlet openings for beizumischendes gas,</li><li><figref idrefs="f0002">FIG. 2</figref> a schematic view of the venturi tube of the mixer, wherein the tube region of narrowed cross-section in which the inlet openings are provided for the ready for incorporation gas, is surrounded by a control sleeve, which is rotatable on the pipe portion, for rotating one of a control mechanism acted upon, flexible to provided stiffer spring thrust strip, </li><li><figref idrefs="f0002">Fig. 3</figref> the venturi tube with the control sleeve and the plastic strip used for adjusting in side view,</li><li><figref idrefs="f0002">Fig. 4</figref> a diagrammatic representation of the control sleeve,</li><li><figref idrefs="f0003">Fig. 5</figref> a section through the mixer to display the deflection and following the plastic strip to the inner housing wall,</li><li><figref idrefs="f0004">Fig. 6</figref> a variant of Verdrehantriebes for control sleeve having a rigid connecting rod,</li><li><figref idrefs="f0004">Fig. 7</figref> diagrammatically a variant of the mixer with a toothed belt drive of the control sleeve,</li><li><figref idrefs="f0004">Fig. 8</figref> the venturi tube with a control sleeve shown in exploded view, two-part,</li><li><figref idrefs="f0005">Fig. 9</figref> a control sleeve, wherein the attack sprocket of the toothed belt is provided between two rows of fuel control orifices,</li><li><figref idrefs="f0005">Fig. 10</figref> the fuel control ring on the barrel portion of the Venturi tube of restricted cross-section,</li><li><figref idrefs="f0006">Fig. 11</figref> the housing of the mixer with two inlet ports for different fuel gases, wherein in the cross section of the venturi tube to the central arrangement of the Zeppelin-shaped gas displacement body is seen</li><li><figref idrefs="f0006">Fig. 12</figref> the housing of the mixer with a view port for controlling the rotational position of the control sleeve,</li><li><figref idrefs="f0003">Fig. 13</figref> a longitudinal section through the venturi tube for displaying the zeppelin shaped gas displacement body.</li><li><figref idrefs="f0001">Fig. 14</figref> a longitudinal section through the hollow Gasverdrändungskörper.</li></ul>

p0024<figref idrefs="f0001">Fig. 1</figref> shows that are a consumer, for example, supplied to an internal combustion engine includes a mixer for gaseous media. The mixer 1 consists of a housing 2, in which a Venturi tube 3 is located. Through the inlet 4 of the venturi tube 3, air is sucked into the downstream located combustion engine. The Venturi tube 3 is arranged in a mixer housing 2, which serves to guide gas.

p0025It is to detect a fuel gas supply 5th Above the housing 2 there is a control mechanism 6 for a later explained control sleeve, which makes the supply of the fuel gas regulated. The pipe section 7 of the Venturi tube 3 with reduced cross-section is provided with inlet openings 8 for the fuel gas in the pipe section. 7 In tube section 7 of the axis of the Venturi tube 3 is disposed by struts 9 a zeppelin-shaped gas displacement body 10 along.

p0026<figref idrefs="f0002">FIG. 2</figref> shows the core area of ​​the mixer 1 and that the venturi tube 3 with the conically tapered inlet, the narrowed pipe portion 7 and the conically widening outlet 12. In the pipe section 7, the inlet openings can be seen. 8 Via flanges 13, the Venturi tube 3 is inserted in the mixer housing. The pipe section 7 is surrounded by a control sleeve 14, which in<figref idrefs="f0002">Fig. 3</figref> in side view and in <figref idrefs="f0002">Fig. 4</figref> is shown as an individual part. The control sleeve 14 is comprised of a dimensionally stable and self-lubricating material. It is possible that the form-retaining and self-lubricating material of the control sleeve contains stabilizers and lubricating components. The control sleeve may be of metal, ceramic, plastic or a composite material. The material shall meet the requirements to be dimensionally stable and self-lubricating. An example suitable material is Murylat SP ®. Such dimensionally stable and self-lubricating material is for example a plastic.

p0027The control sleeve 14 is provided with fuel gas control openings 15th The openings 8 and 15 correspond to each other, but need not. The control sleeve 14 has a collar 16, on which a more flexible fixed until spring stiffer thrust strips 17th The push rod can for example have a stiffness on the order of a cable tie. The other end of the pushing strip 17 is attached to a reel 18th The roller 18 mounted on a shaft 19 of the control mechanism 6 rotations of the shaft 19 is transferred to the shear web 17, which likewise the rule sleeve rotated 14, is adjusted. The thrust strip 17 rests against the pushing against the wall 20, or a similar type of guide member and is supported on the wall or the guide member. When rotating the control sleeve 14, the inlet openings 8 and the fuel control orifices 15 adjust to today. As a result, that change the remaining open passage sections 21st According to the specifications of a control device, not shown, can be so that of blending of the fuel gas is continuously adapted to the requirements.

p0028In <figref idrefs="f0004">Fig. 6</figref> is shown a variant of the push operation of the control sleeve 14th In this case, a rigid push rod 22 is used, which adjusts the control sleeve fourteenth The push rod 22 is hinged to the roller 18 and on the control sleeve 14 for example by means of ball joints 23rd

p0029<figref idrefs="f0004">Fig. 7</figref> shows a drive for rotating the control sleeve 14 through a toothed belt 24. The control sleeve 14 is for this purpose with a toothed ring 25 (<figref idrefs="f0005">FIGS. 9 and 10</figref>) Provided. The toothed belt 24 is moved by a pinion 26 and rotated through the sprocket the control sleeve 14. The pinion 26 is driven by the control mechanism 6 according to the specifications of the control device, not shown.

p0030In <figref idrefs="f0004">Fig. 8</figref> is shown in exploded view a two-piece embodiment of the control sleeve 14th The two parts 14a and 14b are plugged together on the barrel portion 7th The alteration of the forward sections 21 during rotation of the control sleeve 14 behaves as if the thrust strips 17 and push rods 22 by the inlet openings 8 and the fuel control openings 15 move towards each other. According to the specifications of the control device, not shown, the of blending of the fuel gas can be continuously adapted to the requirements.

p0031In <figref idrefs="f0005">FIGS. 9 and 10</figref> 14 with ring gear 25, and other forms of fuel control orifices 15 a one-piece control sleeve. The shape and size of the fuel control openings and inlet openings 8 is determined by the throughput volumes. In the<figref idrefs="f0005">FIGS. 9 and 10</figref> the openings are oblong-shaped, 8 and 15. A further modification is that the sprocket 25 is located at a multi-row arrangement of the inlet openings 8 on the venturi pipe and the fuel control orifices 15 at the control sleeve 14 between the openings. The same goes for the collar 16 of the control sleeve, for flexible and rigid pen pusher strip 17 and the engagement portion of the rigid connecting rod 22nd<figref idrefs="f0005">Fig. 9</figref> shows the control sleeve 14 alone. In<figref idrefs="f0005">Fig. 10</figref> it is slid over the narrowed pipe portion 7 of the venturi third Recognizable is also how the passage sections 21 remain free between the inlet openings 8 and the fuel control orifices 15th

p0032The collar 16 and the sprocket 25 can for all variants of the control sleeve 14 at a sleeve side such as in <figref idrefs="f0002">Fig. 4</figref> or in the middle between the fuel control apertures 15 as shown in <figref idrefs="f0005">FIGS. 9 and 10</figref> be provided. It is also possible to place the fuel control openings at the sleeve edges, they may be open to the flanks usually sleeves.

p0033<figref idrefs="f0006">Fig. 11</figref> shows a mixer 1 with two sockets 5 for the supply of various fuel gases. In the channel 7 of the Venturi tube 3 can be seen as extending along the axis of the Venturi tube 3 extending zeppelin-shaped body 10 is suspended on the struts. 9

p0034The struts 9 may be hollow in order to align continuously for the purpose of a gas transport with the openings 8, and in this case have their part openings 30, preferably on both sides of the / each strut, in particular in the rear part of the strut (in terms of the flow direction) and / or discontinued at the end in the body 10th

p0035<figref idrefs="f0006">Fig. 12</figref> shows how the mixer housing 2, a window 27 is provided, it can be observed by which position the control sleeve 14 has at the moment of insight. We see a reference line 28 to the mixer housing 2 and a barcode 29 on the control sleeve 14. In this way, a visual check of the size of the passage cross sections are possible.

p0036<figref idrefs="f0003">Fig. 13</figref> shows a longitudinal section through the venturi tube 3. On the basis of the longitudinal section can be seen the zeppelin-like body in the canal. 7 The zeppelin-shaped body is interchangeable. Thus, the passage cross section of the channel is variable. This variation, however, is more static, as an exchange is not possible during operation. So it is a to be carried out before the start of operation adjustment.

p0037<figref idrefs="f0001">Fig, 14</figref> shows a longitudinal section through a hollow Gasverdrändungskörper 10 in Zeppelin form. Further shown are the internal end of the hollowed teardrop-shaped struts 9, with which the gas displacement body in the Venturi tube is fixed and is passed through the fuel gas into the hollow interior of the gas displacement body. Through the outlet openings 31 in the gas displacement body on the outer circumferential surface beyond the two end faces, the gas / combustion gas is (possibly proportional) introduced into the interior region of the Venturi tube.