Laminar flow meter

Abstract

This invention discloses a laminar flow meter, comprising a fluid detection module and a measurement and calculation module disposed outside the fluid detection module. The fluid detection module includes a housing and a laminar fluid that cooperates with the housing, the laminar fluid comprising a plurality of overlapping and stacked laminar flow units. The measurement and calculation module includes a temperature sensor, a pre-pressure sensor, a post-pressure sensor, and a calculator, the calculator being connected to the data terminals of the temperature sensor, the pre-pressure sensor, and the post-pressure sensor. The detection terminals of the temperature sensor, the pre-pressure sensor, and the post-pressure sensor are connected to the fluid detection module. This invention solves the technical problems of poor accuracy and high operating condition requirements of existing laminar flow meters.

Description

Technical Field

[0001] This invention relates to the field of flow measurement, and particularly to a laminar flow meter. Background Technology

[0002] Laminar flow meters are measuring tools designed based on the Hagen-Poiseuille Law to accurately measure fluid flow rate. Existing laminar flow meters utilize various methods to design flow elements, transforming the turbulent, disordered state of the fluid into a laminar state. However, in practical use, they suffer from varying degrees of instability and low accuracy. Secondly, most laminar flow meters separate the housing, laminar flow element, and calculation module. While this reduces manufacturing difficulty, it results in excessive size, low integration, and difficulty in large-scale deployment. Furthermore, some new technologies have been applied to laminar flow meters, but mass production has not yet materialized, leading to increased dispersion in experimental data and hindering the achievement of mass production goals. Moreover, the internal isolation units of the laminar flow element in existing technologies are not strictly designed according to the requirements of the laminar flow state, causing inconsistencies between the calculation formula and the laminar flow state. This results in the inability to complete measurement tasks under many operating conditions and poor portability. Summary of the Invention

[0003] The purpose of this invention is to provide a laminar flow meter that solves the technical problems of poor accuracy and high operating requirements of existing laminar flow meters.

[0004] The technical solution adopted in this invention is: a laminar flow meter, which includes a fluid detection module and a measurement and calculation module placed outside the fluid detection module;

[0005] The fluid detection module includes a housing and a laminar fluid that cooperates with the housing. The laminar fluid includes several overlapping and stacked laminar flow units.

[0006] The measurement and calculation module includes a temperature sensor, a pre-pressure sensor, a post-pressure sensor, and a calculator. The calculator is connected to the data terminals of the temperature sensor, the pre-pressure sensor, and the post-pressure sensor. The detection terminals of the temperature sensor, the pre-pressure sensor, and the post-pressure sensor are connected to the fluid detection module.

[0007] Furthermore, the shell and the laminar fluid that cooperates with the shell are specifically provided with protrusions on both sides of the laminar fluid that contact the shell, and the shell is provided with recesses at the corresponding positions of the protrusions.

[0008] Furthermore, the laminar flow unit includes an upper laminar flow plate, a lower laminar flow plate, and a laminar flow rack. The upper laminar flow plate and the lower laminar flow plate are stacked and overlapped. Laminar flow racks are respectively arranged on both sides between the upper laminar flow plate and the lower laminar flow plate. The upper laminar flow plate, the lower laminar flow plate, and the two laminar flow racks form a flow channel through which the fluid passes.

[0009] Furthermore, the upper and lower wafers have the same external dimensions and both are provided with protrusions, with corresponding protrusions and recesses.

[0010] Furthermore, both the upper and lower flow plates are provided with front and rear pressure measurement holes. The front and rear pressure measurement holes on the upper flow plate are in the same positions as those on the lower flow plate, forming a through-hole and a through-hole in the vertical direction that connect the upper and lower flow plates. The front pressure measurement through-hole is connected to the front pressure sensor, and the rear pressure measurement through-hole is connected to the rear pressure sensor.

[0011] Furthermore, both the upper and lower wafers have notches at the upstream axis in the flow direction.

[0012] Furthermore, the laminar flow rack is elongated, with a protrusion on the side adjacent to the shell, and the protrusion and the recess are arranged correspondingly.

[0013] Furthermore, there are two protrusions.

[0014] Furthermore, the upper flow layer, lower flow layer, and laminar flow rack have the same thickness.

[0015] Compared with existing technologies, the laminar flow meter provided by the above technical solution has the following advantages:

[0016] (1) The layout of temperature and pressure sensors makes the acquisition of temperature and pressure more accurate and more suitable for the calculation characteristics of Hagen-Poiseuille law.

[0017] (2) The design of the laminar flow element and the housing allows the fluid to concentrate and pass through the flow channel, making the measurement data more accurate and thus obtaining more accurate results;

[0018] (3) The design of the laminar flow rack replaces the laminar flow barrier, making the fluid in the flow channel more in line with the laminar flow state, thereby eliminating technical bias and making the results more universal. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a laminar flow meter;

[0020] Figure 2 This is a schematic diagram of the interaction between the shell and the laminar fluid;

[0021] Figure 3 This is a schematic diagram of a laminar flow unit;

[0022] Figure 4 This is a schematic diagram of a laminar flow rack. Detailed Implementation

[0023] Example 1:

[0024] like Figure 1As shown, a laminar flow meter includes: the laminar flow meter includes a fluid detection module 1 and a measurement and calculation module 2 placed outside the fluid detection module 1;

[0025] The fluid detection module 1 includes a housing 11 and a laminar fluid 12 that cooperates with the housing 11. The laminar fluid 12 includes a plurality of overlapping and stacked laminar flow units.

[0026] The measurement and calculation module 2 includes a temperature sensor 21, a pre-pressure sensor 22, a post-pressure sensor 23, and a calculator 24. The calculator 24 is connected to the data terminals of the temperature sensor 21, the pre-pressure sensor 22, and the post-pressure sensor 23. The detection terminals of the temperature sensor 21, the pre-pressure sensor 22, and the post-pressure sensor 23 are connected to the fluid detection module 1.

[0027] The above embodiments are described below. The main component of the laminar flow meter is the laminar fluid 12, also known as a laminar flow unit or laminar flow element. Its main purpose is to convert turbulent and disordered fluid into a laminar flow state. The fluid is not limited to air or liquid; under special operating conditions, it also includes situations where air and liquid coexist, solid and liquid coexist, or air, solid, and liquid coexist. In this embodiment, the laminar fluid 12 is constructed by stacking laminar flow units, resulting in a more stable laminar flow state compared to capillary or slit-type laminar fluids. In fact, every fluid flowing within the laminar fluid 12 is in a laminar flow state. According to the Hagen-Poiseuille law, to obtain the flow rate value of the fluid, it is necessary to know the fluid temperature and the pressure difference at a certain distance under laminar flow conditions (obtained in this embodiment by the front pressure sensor 22 and the rear pressure sensor 23). When calculating the flow rate value, the pressure value and pressure difference value are usually required in the pressure term. These two parameters are obtained by simply adapting the parameters obtained in this embodiment using existing technology. In existing technologies, temperature is obtained in two ways: indirectly and directly. The indirect method involves measuring the temperature of the shell or fluid layer in contact with the fluid, while the direct method involves directly measuring the temperature of the fluid itself. This embodiment uses the direct measurement method. Although the temperature sensor 21 is shown in a vertical arrangement in the schematic diagram, experimental results show that placing the temperature sensor horizontally also yields good measurement results. Under special conditions, such as in the presence of solid and liquid, the measurement results are closer to the true value of the fluid. In pressure measurement, some technologies directly export the fluid to the fluid detection module 1, constructing two enclosed measurement spaces upstream and downstream outside the fluid detection module 1, and using the pressure difference between the upstream and downstream measurement spaces as the basis for calculating the flow rate. Obviously, this method is also an indirect measurement method. This embodiment uses the fluid layer 12 itself as the inspection unit to directly obtain the pressure difference value, thus achieving greater accuracy than existing technologies. Furthermore, this embodiment does not make any special improvements to the calculator 24. Any chip or internal (external) processor with computing capabilities that can embed programs and parameters can be used as the calculator 24 in this embodiment. For greater ease of use, this example can be connected to an external or built-in monitor. Since monitors are existing technology, they will not be discussed further here.

[0028] Through this embodiment, the following beneficial effects can be obtained: obtaining more stable laminar flow, more accurate temperature and pressure difference values, and thus obtaining more accurate results.

[0029] Example 2:

[0030] like Figure 1-3As shown, based on Embodiment 1, this embodiment makes the following improvements: the shell 11 and the laminar fluid 12 that cooperates with the shell 11 are specifically provided with protrusions 121 on both sides of the laminar fluid 12 that contact the shell 11, and the shell 11 is provided with recesses 111 at the corresponding positions of the protrusions 121.

[0031] Since the laminar fluid 12 is formed by overlapping and stacking laminar flow units, it faces the technical challenge of fixing these units together to prevent displacement. Existing technologies sometimes use adhesives for bonding, but the thickness of the adhesive itself makes the relevant parameters non-unique and difficult to determine. Others use bolts and nuts for fixing, but this method is more common when the laminar fluid is separated from the shell. When the laminar fluid is separated from the shell, the fluid flows through the gap between them, and the fluid is not entirely in a laminar state, increasing turbulence and causing greater pressure fluctuations at the pressure measurement points. This alters the basis of the Hagen-Poiseuille law, making the measurement results unstable and leading to larger errors. The protrusion 121 and the recess 111 work together to effectively prevent fluid from flowing between the laminar fluid 12 and the shell 11, and also to limit the position of the laminar fluid 12. Furthermore, in the vertical direction, extreme stacking or the addition of solid pressure plates can be used to compact the fluid, thereby limiting vertical displacement. It should be noted that although protrusion 121 is presented as a semi-circle in the schematic diagram, in practice it can be combined with various triangles, rectangles or other forms.

[0032] Furthermore, the laminar flow unit includes an upper laminar flow vane 122, a lower laminar flow vane 124, and a laminar flow frame 123. The upper laminar flow vane 122 and the lower laminar flow vane 124 are stacked and overlapped. Laminar flow frames 123 are respectively arranged on both sides between the upper laminar flow vane 122 and the lower laminar flow vane 124. The upper laminar flow vane 122, the lower laminar flow vane 124, and the two laminar flow frames 123 form a flow channel for fluid passage. The upper laminar flow vane 122 and the lower laminar flow vane 124 have the same external dimensions and are both provided with protrusions 121, which are correspondingly arranged with recesses 111.

[0033] Although the flow channel in this embodiment is rectangular, different shapes may result from different laminar flow rack 123 shapes. The laminar flow rack 123 is just one possible design, and there are many ways in the prior art that can be improved without innovation, and such improvements are all protected by this embodiment.

[0034] By adopting this embodiment, the following beneficial effects can be obtained: the laminar flow element and the housing are designed to fit together, allowing the fluid to concentrate and pass through the flow channel, making the measurement data more accurate and thus obtaining more accurate results; the laminar flow rack replaces the traditional design, making the fluid in the flow channel more in line with the laminar flow state, thereby eliminating technical bias and making the results more universal.

[0035] Example 3:

[0036] like Figure 1-4 As shown, based on the above embodiment, the improvement of this embodiment is that: both the upper flow plate 122 and the lower flow plate 124 are provided with a front pressure measuring hole 125 and a rear pressure measuring hole 126. The front pressure measuring hole 125 and the rear pressure measuring hole 126 provided on the upper flow plate 122 are in the same position as the front pressure measuring hole 125 and the rear pressure measuring hole 126 provided on the lower flow plate 124, forming a front pressure measuring through hole and a rear pressure measuring through hole in the vertical direction. The front pressure measuring through hole is connected to the front pressure sensor 22, and the rear pressure measuring through hole is connected to the rear pressure sensor 23.

[0037] The design of the front and rear pressure measurement through holes ensures that the pressure values ​​of all laminar flows in the laminar fluid 12 are equal, and the fluid is directly connected to the detection device through the through holes, so that the obtained pressure value is closest to the true state of the fluid.

[0038] Furthermore, both the upper flow vane 122 and the lower flow vane 124 have notches 127 at their upstream axes in the flow direction. These notches effectively divide the fluid uniformly, reducing the path for the transition from turbulent to laminar flow. The notch 127 can be semi-circular, other shapes, or it can protrude outwards.

[0039] Furthermore, the laminar flow rack 123 is elongated, with a protrusion 121 on the side adjacent to the housing 11, and the protrusion 121 is correspondingly arranged with a recess 111. There are two protrusions 121. The upper laminar flow plate 122, the lower laminar flow plate 124, and the laminar flow rack 123 have the same thickness, although the thickness can be different. In this example, there are two protrusions 121 on one side, but if one, three, or even more are used, the measurement results can still be obtained with little difference. Therefore, simply adding up the number does not constitute a new technical solution. In addition, changes in the thickness of the upper laminar flow plate, the lower laminar flow plate, and the laminar flow rack do not constitute a new technical solution different from this embodiment. Therefore, a simple technical solution that increases the thickness of each component is also within the protection scope of this embodiment.

[0040] The advantage of using the technical solution in this embodiment is that more accurate measurement results can be obtained.

[0041] In summary, compared with existing technologies, the laminar flow meter provided by the above technical solution has the following advantages:

[0042] (1) The design of temperature and pressure sensors makes the acquisition of temperature and pressure more accurate and more suitable for the calculation characteristics of Hagen-Poiseuille law.

[0043] (2) The design of the laminar flow element and the housing allows the fluid to concentrate and pass through the flow channel, making the measurement data more accurate and thus obtaining more accurate results;

[0044] (3) The design of the laminar flow rack replaces the laminar flow barrier, making the fluid in the flow channel more in line with the laminar flow state, thereby eliminating technical bias and making the results more universal.

[0045] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A laminar flow meter, characterized in that, The laminar flow meter includes a fluid detection module (1) and a measurement and calculation module (2) located outside the fluid detection module (1); The fluid detection module (1) includes a housing (11) and a laminar fluid (12) that cooperates with the housing (11). The laminar fluid (12) includes a plurality of overlapping and stacked laminar flow units. The measurement and calculation module (2) includes a temperature sensor (21), a pre-pressure sensor (22), a post-pressure sensor (23), and a calculator (24). The calculator (24) is connected to the data terminals of the temperature sensor (21), the pre-pressure sensor (22), and the post-pressure sensor (23). The detection terminals of the temperature sensor (21), the pre-pressure sensor (22), and the post-pressure sensor (23) are connected to the fluid detection module (1). The laminar flow unit includes an upper laminar flow plate (122), a lower laminar flow plate (124), and a laminar flow rack (123). The upper laminar flow plate (122) and the lower laminar flow plate (124) are stacked and overlapped. Laminar flow racks (123) are respectively provided on both sides between the upper laminar flow plate (122) and the lower laminar flow plate (124). The upper laminar flow plate (122), the lower laminar flow plate (124), and the two laminar flow racks (123) form a flow channel through which the fluid passes. Both the upper flow plate (122) and the lower flow plate (124) have notches (127) at the upstream axis in the flow direction.

2. The laminar flow meter according to claim 1, characterized in that, Specifically, the shell (11) and the laminar fluid (12) that cooperates with the shell (11) are provided with protrusions (121) on both sides of the laminar fluid (12) that contact the shell (11), and the shell (11) is provided with recesses (111) at the corresponding positions of the protrusions (121).

3. A laminar flow meter according to claim 2, characterized in that, The upper layer wafer (122) and the lower layer wafer (124) have the same external dimensions and are both provided with protrusions (121), and the protrusions (121) are provided in correspondence with the recesses (111).

4. A laminar flow meter according to claim 3, characterized in that, Both the upper flow plate (122) and the lower flow plate (124) are provided with a front pressure measuring hole (125) and a rear pressure measuring hole (126). The front pressure measuring hole (125) and the rear pressure measuring hole (126) provided on the upper flow plate (122) are in the same position as the front pressure measuring hole (125) and the rear pressure measuring hole (126) provided on the lower flow plate (124). A front pressure measuring through hole and a rear pressure measuring through hole are formed in the vertical direction, which penetrate the upper flow plate (122) and the lower flow plate (124). The front pressure measuring through hole is connected to the front pressure sensor (22), and the rear pressure measuring through hole is connected to the rear pressure sensor (23).

5. A laminar flow meter according to claim 3 or 4, characterized in that, The laminar flow rack (123) is long and narrow, and a protrusion (121) is provided on the side adjacent to the shell (11). The protrusion (121) is provided in correspondence with the recess (111).

6. A laminar flow meter according to claim 3 or 4, characterized in that, The number of protrusions (121) is 2.

7. A laminar flow meter according to claim 3 or 4, characterized in that, The upper flow plate (122), the lower flow plate (124), and the laminar flow rack (123) have the same thickness.

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