Device for measuring the density of a gas and gas duct system

Abstract

The present invention relates to a device (10) for measuring the density of a gas, comprising a condenser (100) with a condenser housing (110), at least two electrodes (120), and at least one fabric (130), wherein the at least two electrodes (120) are arranged in the condenser housing (110), wherein the at least one fabric (130) comprises an electrically insulating material and is arranged in a space (140) between the at least two electrodes (120), and wherein the condenser housing (110) has at least one first opening (11) which is designed such that the gas can be guided through the at least one first opening (111) into the space (140).

Description

State of the art

[0001] The present invention relates to a device for measuring a density of a gas and a gas guidance system.

[0002] Gas pipelines are used in various technical and industrial applications, particularly for the use of hydrogen gas for energy generation. In these applications, it is often necessary to monitor various gas properties. These properties include the gas density.

[0003] For example, electrical capacitors can be used to measure the density of a gas, as there is a relationship between the density and the electrical permittivity of a gas. To ensure sufficient measurement accuracy, capacitors with large capacitance are necessary. Since the space between the electrodes must be filled with the gas to be measured, it is difficult to ensure the isolation of the electrodes from each other with capacitors of small dimensions.

[0004] The document EP 2 207 020 A2 describes a pressure sensor in which the capacitance of a capacitor is changed by deflecting one of the electrodes under the influence of gas pressure. Disclosure of the invention

[0005] With the present invention, densities of gases in gas supply systems can be measured in an advantageously improved manner.

[0006] According to the invention, a device for measuring a density of a gas having the features of patent claim 1 and a gas guidance system having the features of patent claim 1 are therefore provided.

[0007] Accordingly, a device for measuring the density of a gas is provided, comprising a capacitor having a capacitor housing, at least two electrodes, and at least one fabric. The at least two electrodes are arranged in the capacitor housing. The at least one fabric comprises an electrically insulating material and is arranged in a space between the at least two electrodes. The capacitor housing has at least one first opening, which is designed such that the gas can be guided through the at least one first opening into the space.

[0008] Furthermore, a gas supply system, in particular for supplying a fuel cell, is provided with at least one device according to the invention for measuring a density of a gas

[0009] One idea of ​​the invention lies in the use of a fabric to insulate the electrodes of a capacitor. With a suitable selection of the fabric, the gas whose density is to be measured can flow through and into the cavities between the fibers of the fabric. The density of the gas in the space between the electrodes of the capacitor can then be measured by measuring the capacitance of the capacitor, since there is a direct relationship between the density of a gas and its electrical permittivity.

[0010] Advantageous embodiments and further developments emerge from the further subclaims and from the description with reference to the figures.

[0011] According to a preferred embodiment of the device, the capacitor is designed as a multilayer capacitor. This design advantageously allows high capacitances to be achieved even with small capacitor dimensions.

[0012] According to a further embodiment of the device, the capacitor is designed as a wound capacitor. This design advantageously allows high capacitances to be achieved even with small capacitor dimensions.

[0013] According to a further embodiment of the device, the capacitor comprises a plurality of fabrics arranged such that one fabric is located in each space between two electrodes. This can advantageously increase the measurement accuracy of the device.

[0014] According to a further embodiment of the device, the capacitor housing has a plurality of first openings arranged such that gas can be passed through each of the plurality of first openings into one of the spaces between two electrodes. This advantageously ensures the uniformity of the gas density in the spaces and outside the device.

[0015] According to a further embodiment of the device, the capacitor housing has at least one second opening, which is designed such that the gas can be guided out of the intermediate space through the at least one second opening. This advantageously ensures the uniformity of the gas density in the intermediate spaces and outside the device.

[0016] According to a further embodiment, the device further comprises a device housing with at least one housing opening, wherein the capacitor is arranged in the device housing, and wherein the at least one housing opening is designed such that the gas can be guided into and / or out of the device housing through the at least one housing opening. This advantageously ensures the uniformity of the density of the gas in the interstices and outside the device. Furthermore, protecting the capacitor by the device housing results in advantageous design freedom with regard to the embodiment of the capacitor.

[0017] According to a further embodiment, the device further comprises an evaluation device configured to measure the capacitance of the capacitor and calculate the density of the gas therefrom. This advantageously allows the density to be calculated directly on-site by the device.

[0018] According to a further embodiment, the gas supply system comprises a plurality of devices for measuring the density of a gas, which are arranged at various locations within the gas supply system. This advantageously allows the gas densities to be monitored at various points within the gas supply system. Drawings

[0019] The present invention is explained in more detail below with reference to the exemplary embodiments shown in the schematic figures. They show: Fig. 1 is a schematic representation of a gas guidance system according to an embodiment of the present invention; Fig. 2 is a schematic representation of a device for measuring a density of a gas according to an embodiment of the present invention; and Fig. 3 a schematic representation of a gas guidance system according to an embodiment of the present invention.

[0020] The accompanying figures are intended to provide a further understanding of embodiments of the invention. They illustrate embodiments and, in conjunction with the description, serve to explain principles and concepts of the invention. Other embodiments and many of the noted advantages will become apparent upon review of the drawings. Elements of the drawings are not necessarily shown to scale relative to one another.

[0021] In the figures of the drawing, identical, functionally identical and acting elements, features and components are provided with the same reference symbols, unless otherwise stated. Description of the embodiments

[0022] Fig. 1 shows a schematic representation of a gas guidance system 1 according to an embodiment of the present invention.

[0023] The Fig. The gas guidance system 1 shown in Figure 1 comprises two devices 10 for measuring a density of a gas, a gas tank 20 and a gas line 30. One of the two devices 10 for measuring a density of a gas is arranged in the gas tank 20. The other of the two devices 10 for measuring a density of a gas is arranged in the gas line 30. The gas line 30 is arranged in the Fig. 1, is connected to a fuel cell 2. Gas, in the present embodiment hydrogen gas, can thus be conducted from the gas tank 20 to the fuel cell 2 through the gas line 30.

[0024] With the help of the two devices 10 for measuring a density of a gas, the density of the hydrogen gas can be measured both in the gas tank 20 and in the gas line 30. Possible modes of operation of the two devices 10 for measuring a density of a gas are described in detail with reference to the Fig. 2 and Fig. 3 described.

[0025] Fig. 2 shows a schematic representation of a device 10 for measuring a density of a gas according to an embodiment of the present invention.

[0026] The device 10 for measuring the density of a gas comprises a capacitor 100 with a capacitor housing 110, two electrodes 120, and a fabric 130. The two electrodes 120 are arranged in the capacitor housing 110. The fabric 130 is arranged in a gap 140 between the two electrodes 120. The capacitor housing 110 has a first opening 11, which is designed such that the gas can be guided through the first opening 111 into the gap 140.

[0027] The fabric 130 comprises an electrically insulating material and prevents contact between the two electrodes 120. The fabric 130 is designed such that the molecules of the gas introduced into the intermediate space 140 through the first opening 111 can flow through and into the cavities between the fibers of the fabric 130. The capacitance of the capacitor 100 is determined via the relationship between the density of the gas and its electrical permittivity. By measuring the capacitance of the capacitor 100, the density of the gas can then be determined conversely. Since, at hydrostatic equilibrium, the gas in the intermediate space 140 has the same density as outside the device 10, determining the density of the gas in the intermediate space 140 simultaneously determines the density of the gas outside the device.

[0028] The Fig. The device 10 shown in Figure 2 has only a first opening 111 in the condenser housing 110. In the case of non-flowing or very slow-flowing gas, this one opening is sufficient to establish a hydrostatic equilibrium with the environment of the device 10. The device 10 shown here can therefore be installed, for example, in a gas tank 20 as in Fig. 1 shown.

[0029] Fig. 3 shows a schematic representation of a gas guidance system 1 according to an embodiment of the present invention.

[0030] The Fig. The gas guidance system 1 shown in Figure 3 comprises a device 10 for measuring the density of a gas and a gas line 30. The device 10 for measuring the density of a gas comprises a condenser 100, a device housing 200, and an evaluation device 300. The device housing 200 is arranged in the gas line 30. The condenser 100 is arranged in the device housing 200. The evaluation device 300 is arranged outside the gas line 30.

[0031] The capacitor 100 shown here is designed as a multilayer capacitor with a plurality of electrodes 120 and a plurality of fabrics 130. The plurality of electrodes 120 are arranged in the capacitor housing 110. The plurality of fabrics 130 are each arranged in the spaces 140 between two electrodes 120. The capacitor housing 110 has a plurality of first openings 111, which are designed such that the gas can be guided through each of the plurality of first openings 111 into one of the spaces 140. The capacitor housing 140 further has a plurality of second openings 112, which are designed such that the gas can be guided out of one of the spaces 140 through each of the plurality of second openings 112.

[0032] The device housing 200 has two housing openings 210. One of the two housing openings 210 is configured such that the gas can be directed into the device housing 200 through the first housing opening 210. The second of the two housing openings 210 is configured such that the gas can be directed out of the device housing 200 through the second housing opening 210.

[0033] The arrangement of the housing openings 210 as well as the first openings 111 and second openings 112 of the condenser housing 110 ensures a largely laminar flow of the gas through the device 10. This results in the gas inside the device 10 having the same density as the gas outside the device 10. The evaluation device 300 measures the capacitance of the condenser 100 and uses this to calculate the density of the gas in the gaps 140 and thus also of the gas in the gas line 30.

[0034] The design of capacitor 100 as a multilayer capacitor enables high capacitances and thus greater measurement accuracy, even with small dimensions of capacitor 100. This result can also be achieved using a wound capacitor, particularly a wound film capacitor. The different capacitor types each have their own advantages regarding manufacturing, stability, and contacting of the capacitors.

[0035] In the Fig.In the embodiment shown in Figure 3, only the capacitor 100 is arranged within the device housing 200. It is also conceivable to arrange the evaluation device 300 within the device housing 200. It is also possible to arrange devices for measuring further properties of the gas in the device housing 200. It is also conceivable to use the evaluation device 300 to evaluate data from a plurality of capacitors 100 arranged at different locations in the gas supply system 1, which are arranged in other device housings 200. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 2 207 020 A2

[0004]

Claims

[1] Device (10) for measuring a density of a gas with a capacitor (100) having a capacitor housing (110), at least two electrodes (120), and at least one fabric (130); wherein the at least two electrodes (120) are arranged in the capacitor housing (110); wherein the at least one fabric (130) comprises an electrically insulating material and is arranged in a space (140) between the at least two electrodes (120); and wherein the capacitor housing (110) has at least one first opening (11) which is designed such that the gas can be guided through the at least one first opening (111) into the intermediate space (140). [2] Device (10) according to claim 1, wherein the capacitor (100) is designed as a multilayer capacitor. [3] Device (10) according to one of claims 1 or 2, wherein the capacitor (100) is designed as a wound capacitor. [4] Device (10) according to one of claims 2 or 3, wherein the capacitor (100) comprises a plurality of fabrics (130) arranged such that a fabric (130) is arranged in each space (140) between two electrodes (120). [5] Device (10) according to one of claims 2 to 4, wherein the capacitor housing (110) has a plurality of first openings (110) arranged such that gas can be passed through each of the plurality of first openings (110) into one of the spaces (140) between two electrodes (120). [6] Device (10) according to one of the preceding claims, wherein the capacitor housing (110) has at least one second opening (112) which is designed such that the gas can be guided out of the intermediate space (140) through the at least one second opening (112). [7] Device (10) according to one of the preceding claims, further comprising a device housing (200) with at least one housing opening (210), wherein the capacitor (100) is arranged in the device housing (200), and wherein the at least one housing opening (210) is designed such that the gas can be guided through the at least one housing opening (210) into the device housing (200) and / or out of the device housing (200). [8] Device (10) according to one of the preceding claims, further comprising an evaluation device (300) which is designed to measure the capacitance of the capacitor (100) and to calculate the density of the gas therefrom. [9] Gas supply system (1), in particular for supplying a fuel cell (2), with at least one device (10) for measuring a density of a gas according to one of claims 1 to 7. [10] Gas guidance system (1) according to claim 9, comprising a plurality of devices (10) for measuring a density of a gas, which are arranged at different locations of the gas guidance system (1).

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