METHOD FOR ADJUSTING THE VOLUMETRIC FLOW RATIO OF AT LEAST TWO DIFFERENT FLUIDS

Abstract

Method for adjusting the volumetric flow ratio of at least two different fluids (F1, F2) with a control-device. The control-device comprises a first chamber with a chamber-volume (V.sub.C1) for the first fluid (F1) and an inlet-element and an outlet-element for the first fluid (F1) and at least one rotating or nutating element. The control-device further comprises at least one second chamber with a chamber-volume (V.sub.C2) for the second fluid (F2), wherein the second chamber has an inlet-element and an outlet-element for the second fluid (F2) and at least one rotating or nutating element. The rotating or nutating elements are coupled so as to rotate or nutate at a defined rotational or nutational frequency ratio and are driven by the fluids (F1, F2). The chamber volume ratio (V.sub.C1:V.sub.C2) and the rotational or nutational frequency ratio are selected such that the fluids (F1, F2) flowing out of the outlet-elements have a predefined volumetric flow ratio. The input resistor (R.sub.i) of the respective inlet-element and the output resistor (R.sub.o) of the respective outlet-element of the first chamber and/or the second chamber are chosen so as to satisfy the equation: (I), wherein η.sub.F is the viscosity of the respective fluid (F1, F2) and Cn designates the respective chamber.

Claims

1-16. (canceled)

17. A method for adjusting the volumetric flow ratio of at least two different fluids F1, F2, wherein the volumetric flow ratio between the fluids F1, F2 is adjusted with a control-device, comprising a first chamber with a chamber-volume V.sub.C1 for the first fluid F1, wherein the first chamber has an inlet-element and an outlet-element for the first fluid and at least one rotating or nutating element inside the chamber, at least one second chamber with a chamber-volume V.sub.C2 for the at least one second fluid F2, wherein the second chamber has an inlet-element and an outlet-element for the second fluid and at least one rotating or nutating element inside the chamber, wherein the at least one rotating or nutating element of the first chamber and the at least one rotating or nutating element of the second chamber are coupled so as to rotate or nutate at a defined rotational or nutational frequency ratio, wherein the at least one rotating or nutating element of the first chamber or the at least one rotating or nutating element of the second chamber are/is driven by the first fluid F1 and/or the second fluid F2, wherein the chamber volume ratio VC1:VC2 and the rotational or nutational frequency ratio are selected such that the first fluid flowing out of the outlet-element of the first chamber and the second fluid flowing out of the outlet-element of the second chamber have a predefined volumetric flow ratio and wherein the input resistor R.sub.i of the respective inlet-element and the output resistor R.sub.o of the respective outlet-element of the first chamber and/or the second chamber are chosen so as to satisfy the equation: $\frac{R_{iCn}+R_{oCn}}{{\eta }_F}=R_T\le 10^{14}{m}^{-3},$ wherein η.sub.F is the viscosity of the respective fluid F1, F2 and Cn designates the respective chamber.

18. The method according to claim 17 wherein the input resistor R.sub.i of the respective inlet-element and the output resistor R.sub.o of the respective outlet-element of the first chamber and/or the second chamber are chosen so that R.sub.T is 10.sup.4 m.sup.−3 to 10.sup.14 m.sup.−3.

19. The method according to claim 17, wherein the at least one rotating or nutating element of the first chamber and the at least one rotating or nutating element of the second chamber are coupled directly, preferably by means of a common shaft, so as to rotate at an essentially identical rotational or nutational frequency, so that the volumetric flow ratio between the first fluid and the second fluid is essentially equal to the defined volume ratio of the first and the second chamber V.sub.C1:V.sub.C2.

20. The method according to claim 17, wherein the first chamber and/or the second chamber have a first rotating element and a second counter-rotating element wherein preferably the rotational frequency ratio between the first rotating elements and/or the rotational frequency ratio between the second counter-rotating elements essentially equals 1.

21. The method according to claim 17, wherein the viscosity η.sub.F of the first fluid F1 and/or of the second fluid F2 is 0.5 mPa.Math.s to 10,000 mPa.Math.s.

22. The method according to claim 17, wherein the ratio of the chamber volume V.sub.C1 of the first chamber and the chamber volume V.sub.C2 of the second chamber is 1 to 100.

23. The method according to claim 17, wherein the ratio of the pressure difference Δp.sub.1 between the inlet-element and the outlet-element of the first chamber and the pressure difference Δp.sub.2 between the inlet-element and the outlet-element of the second chamber is less than 1500.

24. The method according to claim 17, wherein the ratio of the R.sub.T(C1)-value of the first chamber and the R.sub.T(C2)-value of the second chamber is less than 1500.

25. The method according to claim 17, wherein the first fluid F1 and the second fluid F2 are selected so as to chemically react upon mixing and wherein at least one of the fluids F1, F2 comprises at least one polyurethane.

26. The method according to claim 17, wherein at least one of the fluids F1, F2 comprises at least one buffer.

27. The method according to claim 17, wherein the ratio of the R.sub.T(C1)-value of the first chamber to the leakage-resistor R.sub.L(C1) of the first chamber and/or the ratio of the R.sub.T(C2)-value of the second chamber to the leakage-resistor R.sub.L(C2))of the second chamber is between 10.sup.−8 and 10.sup.4.

28. The method according to claim 17, wherein the ratio of the flow volume ratio without rotating or nutating elements FR.sub.0 to the theoretical flow volume ratio FR.sub.T is between 0.01 and 100.

29. A control-device for adjusting the volumetric flow ratio of at least two different fluids F1, F2 comprising: a first chamber with a chamber volume V.sub.C1 for the first fluid F1, wherein the first chamber has an inlet-element and an outlet-element for the first fluid F1 and at least one rotating or nutating element inside the chamber, at least one second chamber with a chamber-volume V.sub.C2 for the at least one second fluid F2, wherein the second chamber has an inlet-element and an outlet-element for the second fluid F2 and at least one rotating or nutating element inside the chamber, and wherein the at least one rotating or nutating element of the first chamber and the at least one rotating or nutating element of the second chamber are coupled so as to rotate or nutate at a defined rotational or nutational frequency ratio, wherein the at least one rotating or nutating element of the first chamber and/or the at least one rotating or nutating element of the second chamber are/is driven by the first fluid F1 and/or the second fluid F2.

30. The device according to claim 29 wherein the at least one rotating or nutating element of the first chamber and the at least one rotating or nutating element of the second chamber are mechanically coupled.

31. The device according to claim 29, wherein the first chamber and/or the second chamber have a first rotating element and a second counter-rotating element and wherein the first rotating element (5, 9) and the second counter-rotating element are each gear-wheels, gearing into each other.

32. The device according to claim 29, wherein the device comprises at least one mixing-unit, arranged at the outlet-element of the first chamber and the outlet-element of the second chamber in the direction of flow of the first fluid F1 and the second fluid F2, wherein the mixing-unit is designed to mix the first fluid F1 and the second fluid F2 at the adjusted volumetric flow ratio and wherein the mixing-unit comprises at least one static mixer.

Description

[0050] The invention will now be explained below with reference to a drawing showing just one embodiment. In schematic diagrams:

[0051] FIG. 1: A control-device according to the invention in a first longitudinal sectional view,

[0052] FIG. 2: the control-device of FIG. 1 in a second longitudinal sectional view.

[0053] The figures show a control-device 1 according to the invention for adjusting the volumetric flow ratio between a first fluid F1 and a second fluid F2. The control-device 1 comprises a first chamber 2 with a chamber volume V.sub.C1 for the first fluid F1. This first chamber 2 has an inlet-element 3 and an outlet-element 4 for the first fluid F1. Preferably and according to the shown embodiment, the inlet-element 3 of the first chamber 2 is designed as a circular tube comprising a chamber-sided inlet-opening 17. In the embodiment of FIGS. 1 and 2, the outlet-element 4 of the first chamber 2 consists of a passageway inside the control-device 1 which is connected to a mixing unit 15. The mixing unit 15 is directly coupled to the control-device 1. Inside the first chamber 2, preferably and according to the shown embodiment, a rotating element 5 in the form of an oval gear-wheel is arranged.

[0054] The control-device 1 further comprises a second chamber 6 with a chamber volume V.sub.C2 for the second fluid F2. The second chamber 6 has an inlet-element 7 and an outlet-element 8. According to the preferred embodiment, the inlet-element 7 is designed as an alignment of circular tubes. The inlet-element 7 further comprises a chamber-sided inlet-opening 18. In the embodiment of FIGS. 1 and 2, the outlet-element 8 of the second chamber 6 consists of a passageway inside the control-device 1 which is connected to a mixing unit 15. Inside the second chamber 6, a rotating element 9 in the form of an oval gear is arranged.

[0055] The preferred embodiment of FIGS. 1 and 2 furthermore shows that two fluid reservoirs 13, 14 for the first fluid F1 and the second fluid F2 are provided, which are connected to the respective inlet-elements 3, 7. The chamber volume V.sub.C1 of the first chamber 2 and the chamber volume V.sub.C2 of the second chamber 6 have a defined volume ratio, presently V.sub.C1:V.sub.C2=approximately 2.5:1 (FIG. 1).

[0056] Moreover, preferably and according to the embodiment of the figures, the first chamber 2 and the second chamber 6 of the control-device 1 each have a first rotating element 5, 9 and a second counter-rotating element 11, 12. According to the preferred embodiment, the first rotating elements 5, 9 and the second counter-rotating elements 11, 12 of the two chambers 2, 6 are each embodied as oval gear-wheels gearing into each other as can be best seen in the sectional view of FIG. 2 showing the first rotating element 5 and the second counter-rotating element 11 of the first chamber 2. The second counter-rotating element 12 of the second chamber 6 is not shown in the figures. The rotating elements 5, 11 of the first chamber 2 and the rotating elements 9, 12 of the second chamber 6 are driven by the first fluid F1 and the second fluid F2, respectively. Accordingly, no external drive and energy source is needed for adjusting the volumetric flow ratio between the first fluid F1 and the second fluid F2.

[0057] According to the preferred embodiment of the figures, the first rotating element 5 of the first chamber 2 is directly and mechanically coupled to the first rotating element 9 of the second chamber 6 via a common shaft 10. More preferably and according to the embodiment, the second counter-rotating element 11 of the first chamber 2 is directly and mechanically coupled to the second counter-rotating element 12 of the second chamber 6 via a common shaft 16. In consequence, the first rotating elements 5, 9 of both chambers 2, 6 and the second counter-rotating elements 11, 12 each rotate at an essentially identical rotational frequency. Accordingly, the defined rotational frequency ratios between the first rotating elements 5, 9 and the second counter-rotating elements 11, 12, respectively, essentially each equal 1:1.

[0058] Preferably and in the embodiment according to FIGS. 1 and 2, the frequency ratios between the first rotating elements 5, 9 on the one hand and the second counter-rotating elements 11, 12 on the other hand are essentially identical. Thus, the volumetric flow ratio between the first fluid F1 and the second fluid F2 is essentially equal to the chamber volume ratio V.sub.C1:V.sub.C2. However, to achieve a high degree of flow control, according to the invention, the input resistor R.sub.i of the respective inlet-element 3, 7 and the output resistor R.sub.o of the respective outlet-element 4, 8 of the first chamber 2 and/or the second chamber 6 are chosen so as to satisfy the equation:

[00007]$\frac{R_{iC1/2}+R_{oC1/2}}{{\eta }_F}=R_T\le 10^{14}{m}^{-3},$

wherein η.sub.F is the viscosity of the respective fluid F1, F2.

[0059] Hence, with the control-device 1, it is possible to easily adjust the volumetric flow ratio between the first fluid F1 and the second fluid F2 in a reliable and reproducible manner without the need for an external power source. In the present case, according to the embodiment, the volumetric flow ratio between the first fluid F1 and the second fluid F2 equals approximately 2.5:1.

[0060] Moreover, in a preferred embodiment which is shown in FIG. 2, the control-device 1 comprises a mixing unit 15 which is directly coupled to the control-device 1 and is connected to the outlet-element 4 of the first chamber 2 and the outlet-element 8 of the second chamber 6. The mixing unit 15 is designed to mix the first fluid F1 with the second fluid F2 at the adjusted volumetric flow ratio.

[0061] The first fluid F1 may be a mixture of an alkoxysilane-terminated polymer as disclosed in example 1 of EP 2 760 903 B1 and dimethylether and the second fluid F2 may be an aqueous solution as disclosed in example 12 of EP 2 760 903 B1. Upon mixing the fluids F1, F2, they chemically react to yield a polymer foam.