A micro disc pump with spiral guide vanes

Abstract

The present invention discloses a micro disc pump with spiral guide vanes in the field of micro fluid transport systems, which includes a pump body, a disc, and a driving element for driving the disc to rotate; the pump body is provided with a liquid inlet hole, an arc-shaped flow channel, and a liquid outlet hole that are connected in sequence; the liquid inlet hole and the liquid outlet hole penetrate through the pump body; the arc-shaped flow channel is arranged on the end face of the pump body, and the disc is attached to the end face of the pump body where the arc-shaped flow channel is provided; a spiral guide vane is arranged in the liquid outlet hole; in the present invention, the driving element drives the disc to rotate; the disc shears and does work on the fluid in the arc-shaped flow channel on the pump body, transporting the fluid from the inlet pipe to the outlet pipe; the spiral guide vane converts the circumferential velocity kinetic energy of the fluid in the outlet pipe into pressure energy, improving the hydraulic efficiency of the disc pump.

Description

Technical Field

[0001] The present invention belongs to the technical field of microfluidic transport systems, and particularly relates to a micro disc pump. Background Art

[0002] A disc pump relies on a rotating disc to do work by shearing a fluid, and conveys a fluid with a certain pressure and flow rate, and is applied to fluid transport systems such as sensors, separation devices, and blood transport devices. Under the disc shearing action, the circumferential velocity of the fluid in the flow channel of the disc pump is the dominant motion. When the fluid enters the outlet pipe of the disc pump, the circumferential velocity is still the dominant motion. For the outlet section of a hydraulic machine, the more significant the circumferential motion, the greater the energy loss. The commonly used efficiency enhancement method is to convert the kinetic energy of the circumferential motion into pressure energy, and diffusion pipes, guide vanes, etc. are mostly used. In the published literature, such as "A Design Method of a Micro Disc Pump with a Spiral Flow Channel" (CN202011110377.4), the outlet pipe of the disc pump is a circular pipe and does not have diffuser parts such as guide vanes, and the outlet pipe cannot efficiently convert the kinetic energy of the circumferential velocity of the fluid into pressure energy, resulting in a low efficiency of the disc pump. Summary of the Invention

[0003] The purpose of the present invention is to provide a micro disc pump with a spiral guide vane, which converts the kinetic energy of the circumferential velocity in the outlet pipe of the disc pump into pressure energy and improves the efficiency of the disc pump.

[0004] To achieve the above object, the technical solution adopted by the present invention is:

[0005] A micro disc pump with a spiral guide vane includes a pump body, a disc, and a driving element for driving the disc to rotate; the pump body is provided with a liquid inlet hole, an arc-shaped flow channel, and a liquid outlet hole connected in sequence; the liquid inlet hole and the liquid outlet hole penetrate through the pump body; the arc-shaped flow channel is arranged on the end face of the pump body, and the disc is attached to the end face of the pump body provided with the arc-shaped flow channel; a spiral guide vane is arranged in the liquid outlet hole.

[0006] Preferably, the outer diameter D 4 of the spiral guide vane is 2 equal to the diameter D

[0007] of the liquid outlet hole. 1 Preferably, a coefficient C 1 is selected, and the range of the coefficient C 1 is 0 < C 3 ≤ 0.2; the inner diameter D

[0008] of the spiral guide vane is; 3 D 1 = C 2 ·D

[0009] In formula (1), D 2 is the diameter of the liquid outlet hole, and the unit is m.

[0010] Preferably, it is assumed that the axial velocity in the liquid outlet hole is uniform, and its axial velocity is:

[0011]

[0012] In formula (2), Q is the flow rate of the disc pump, and the unit is m 3 / s; D 2 is the diameter of the liquid outlet hole, and the unit is m; π is the pi.

[0013] Preferably, the inner-edge inlet liquid flow angle β 3,a ' is:

[0014]

[0015]

[0016] Select the inlet attack angle Δβ of the spiral guide vane 3 ; the inner-edge inlet setting angle β of the spiral guide vane 3,a is:

[0017] β 3,a = β 3,a '+ Δβ 3 (5)

[0018] In formula (3) and formula (4), ω is the rotational speed of the disc, and the unit is rad / s; R 2 is the radius of the inner contour line of the circular arc flow channel, and the unit is m.

[0019] The outer-edge inlet liquid flow angle β of the spiral guide vane 3,b ' is:

[0020] v b,u = R 2 ·ω (6)

[0021]

[0022] Select the inlet attack angle Δβ of the spiral guide vane 3 ; the outer-edge inlet setting angle β of the spiral guide vane 3,b is:

[0023] β 3,b = β 3,b '+ Δβ 3 (8)

[0024] In formula (6) and formula (7), ω is the rotational speed of the disc, and the unit is rad / s; R 2 is the radius of the inner contour line of the circular arc flow channel, and the unit is m.

[0025] Preferably, the inner-edge outlet setting angle β 4,a of the spiral guide vane and the outer-edge outlet setting angle β 4,b of the spiral guide vane are both equal to 90 degrees.

[0026] Preferably, the coefficient C 2 is selected, and the pitch S of the spiral guide vane is:

[0027] S = C 2 ·π·D 2 (Nine)

[0028] In the formula, the value range of the coefficient C 2 is 1 ≤ C 2 ≤ 5, π is the pi, and D 2 is the diameter of the liquid outlet hole, with the unit of m.

[0029] Preferably, the coefficient C 3 is selected, and the length L of the spiral guide vane is:

[0030] L = C 3 ·S (Ten)

[0031] In the formula, the value range of the coefficient C 3 is 1 ≤ C 3 ≤ 10, S is the pitch S of the spiral guide vane, with the unit of m.

[0032] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0033] In the pump body of the present invention, there are successively connected liquid inlet holes, arc-shaped flow channels, and liquid outlet holes; the liquid inlet holes and the liquid outlet holes penetrate through the pump body; a spiral guide vane is arranged in the liquid outlet hole; the disk performs shear work on the fluid in the arc-shaped flow channel on the pump body, transporting the fluid from the inlet pipe to the outlet pipe; the spiral guide vane converts the circumferential velocity kinetic energy of the fluid in the outlet pipe into pressure energy, improving the hydraulic efficiency of the disk pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 FIG. is a cross-sectional view of a micro disk pump with a spiral guide vane provided by an embodiment of the present invention;

[0035] Figure 2 FIG. is a top view of the pump body provided by an embodiment of the present invention;

[0036] Figure 3 FIG. is a sectional view of the spiral guide vane provided by an embodiment of the present invention;

[0037] Figure 4 FIG. is a schematic diagram of the inner-edge inlet setting angle of the spiral guide vane provided by an embodiment of the present invention;

[0038] Figure 5It is a schematic diagram of the installation angle at the inlet of the outer edge of the spiral guide vane provided by an embodiment of the present invention;

[0039] In the figure: 1 is a disc, 2 is a pump body, 2-1 is an arc-shaped flow channel, 2-2 is a liquid inlet hole, 2-3 is a liquid outlet hole, 3 is a driving element, and 4 is a spiral guide vane. Specific embodiments

[0040] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention and should not be used to limit the protection scope of the present invention.

[0041] It should be noted that in the description of the present invention, the orientation or positional relationship indicated by the terms "front", "rear", "left", "right", "upper", "lower", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention rather than requiring the present invention to be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention. The terms "front", "rear", "left", "right", "upper", "lower" used in the description of the present invention refer to the directions in the accompanying drawings, and the terms "inner" and "outer" respectively refer to the directions towards or away from the geometric center of a specific component.

[0042] As shown Figures 1-5 A micro disc pump with a spiral guide vane is shown, which includes a pump body 2, a disc 1, and a driving element 3 for driving the disc to rotate; the pump body 2 is provided with a liquid inlet hole 2-2, an arc-shaped flow channel 2-1, and a liquid outlet hole 2-3 connected in sequence; the liquid inlet hole 2-2 and the liquid outlet hole 2-3 penetrate through the pump body 2; the arc-shaped flow channel 2-1 is arranged on the end face of the pump body 2, and the disc 1 is attached to the end face of the pump body 2 provided with the arc-shaped flow channel 2-1; the disc 1 is provided with a circular groove; the pump body 2 is arranged in the circular groove; the disc 1 shears and does work on the fluid in the arc-shaped flow channel 2-1 on the pump body 2, and uses the viscosity of the liquid to transport the fluid from the liquid inlet hole 2-2 to the liquid outlet hole 2-3; the liquid outlet hole 2-3 is provided with a spiral guide vane 4, and the spiral guide vane converts the circumferential velocity kinetic energy of the fluid in the outlet pipe into pressure energy, improving the hydraulic efficiency of the disc pump.

[0043] The physical properties of the transported fluid are: kinematic viscosity υ = 0.0005m 2 / s, density ρ = 800kg / m 3 ; the flow rate of the disc pump is Q = 1×10 -6 m 3 / s; the outer contour line radius of the arc-shaped flow channel 2-1 is R 1 = 0.018m; the inner contour line radius of the arc-shaped flow channel 2-1 is R 2 = 0.002m; the rotational speed of the disc 1 is ω = 1.394rad / s; the diameter D 1 of the liquid inlet hole 2-2 and the diameter D of the liquid outlet hole 2-32 It is equal to 0.016 m.

[0044] The outer diameter D of the spiral guide vane 4 is equal to the diameter D of the liquid outlet hole 2 ; Select the coefficient C 1 , and the coefficient C 1 ranges from 0 < C 1 ≤ 0.2; Take C 1 = 0.1, and the inner diameter D3 of the spiral guide vane is calculated by Equation (2).

[0045] D 3 = C 1 · D 2 = 0.0016 m (1)

[0046] Assume that the axial velocity in the liquid outlet hole 2-3 is uniform, and its axial velocity is calculated by Equation (3).

[0047]

[0048] The inner-edge inlet liquid flow angle β 3,a ' of the spiral guide vane 4 is calculated by Equations (4) and (5):

[0049]

[0050]

[0051] Select the inlet attack angle Δβ 3 of the spiral guide vane 4; The inner-edge inlet setting angle β 3,a of the spiral guide vane 4 is calculated by Equation (6):

[0052] β 3,a = β 3,a ' + Δβ 3 = 24° (5)

[0053] In Equations (3) and (4), ω is the rotational speed of the disk 1, and the unit is rad / s; R 2 is the radius of the inner contour line of the circular arc flow channel, and the unit is m.

[0054] The outer-edge inlet liquid flow angle β 3,b ' of the spiral guide vane 4 is calculated by Equations (7) and (8):

[0055] v b,u = R 2 · ω = 2.788×10 -3 m / s (6)

[0056]

[0057] Select the inlet incidence angle Δβ3 of the spiral guide vane 4; the installation angle β at the inlet of the outer edge of the spiral guide vane 4 3,b Calculate according to Equation (VIII):

[0058] β 3,b = β 3,b '+ Δβ 3 = 63° (VIII)

[0059] In Equations (VI) and (VII), ω is the rotational speed of the disk, with the unit of rad / s; R 2 is the radius of the inner contour line of the arc-shaped flow channel, with the unit of m.

[0060] The installation angle β 4,a at the outlet of the inner edge of the spiral guide vane 4 and the installation angle β 4,b at the outlet of the outer edge of the spiral guide vane 4 are both equal to 90 degrees.

[0061] Select the coefficient C 2 , and the value range of the coefficient C 2 is 1 ≤ C 2 ≤ 5; take C 2 = 5, and the pitch S of the spiral guide vane is calculated according to Equation (IX):

[0062] S = C 2 · π · D 2 = 0.25 m (IX)

[0063] Select the coefficient C 3 , and the value range of the coefficient C 3 is 1 ≤ C 3 ≤ 10; take C 3 = 2, and the length L of the spiral guide vane is calculated according to Equation (X):

[0064] L = C 3 · S = 0.5 m (X)

[0065] Draw the spiral guide vane 4 based on the above main design parameters.

[0066] Since the spiral guide vane 4 increases the local loss and the frictional loss along the flow path of the liquid outlet hole 2-3, use ANSYS to perform numerical simulation on the disk pump with the spiral guide vane, and use Equation (XI) to calculate the conversion rate of the circumferential kinetic energy to the static pressure.

[0067]

[0068] Among them, A 4 is the outlet area of the liquid outlet hole 2-3, with the unit of m 2 ; A 3 is the inlet area of the liquid outlet hole 2-3, with the unit of m 2 ; P 4is the outlet static pressure of the liquid outlet hole 2-3, with the unit of Pa; P 3 is the inlet static pressure of the liquid outlet hole 2-3, with the unit of Pa; v m4 is the outlet normal velocity of the liquid outlet hole 2-3, with the unit of m / s; v m3 is the inlet normal velocity of the liquid outlet hole 2-3, with the unit of m / s; ρ is the density of the working medium of the disc pump, kg / m 3 ; v u4 is the outlet circumferential velocity of the liquid outlet hole 2-3, with the unit of m / s; v u3 is the inlet circumferential velocity of the liquid outlet hole 2-3, with the unit of m / s. Incorporate Equation (XI) into ANSYS, and the calculated conversion rate of circumferential kinetic energy to static pressure is 5.5%; the conversion rate meets the requirements, and the design is completed.

[0069] Working principle: The driving element 3 drives the disc 1 to rotate; the disc 1 shears and does work on the fluid in the arc-shaped flow channel 2-1 on the pump body 2, and utilizes the viscosity of the liquid to transport the fluid from the liquid inlet hole 2-2 to the liquid outlet hole 2-3; a spiral guide vane 4 is provided in the liquid outlet hole 2-3, and the circumferential velocity kinetic energy of the fluid in the outlet pipe is converted into pressure energy through the spiral guide vane to improve the hydraulic efficiency of the disc pump.

[0070] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and deformations can still be made, and these improvements and deformations should also be regarded as the protection scope of the present invention.

Claims

1. A micro disc pump with a spiral guide vane, Characterized in that, It includes a pump body (2), a disc (1), and a driving element (3) for driving the disc to rotate; an inlet hole (2-2), an arc-shaped flow channel (2-1), and an outlet hole (2-3) are sequentially arranged on the pump body; the inlet hole (2-2) and the outlet hole (2-3) penetrate through the pump body (2); the arc-shaped flow channel (2-1) is arranged on the end face of the pump body, and the disc (1) fits with the end face of the pump body (2) where the arc-shaped flow channel (2-1) is provided; a spiral guide vane (4) is arranged in the outlet hole (2-3); Assume that the axial velocity in the outlet hole (2-3) is uniform, and its axial velocity is: ； In the formula, Q is the flow rate of the disc pump, with the unit of m 3 / s; D 2 is the diameter of the liquid outlet hole (2-3), with the unit of m; π is the pi; is the axial velocity of the liquid in the liquid outlet hole (2-3); Inner edge inlet liquid flow angle of the spiral guide vane (4) is: ； ； In the formula, D 4 is the outer diameter of the spiral guide vane (4); D 3 is the inner diameter of the spiral guide vane (4); Select the inlet attack angle Δβ of the spiral guide vane (4) 3 ; The inner edge inlet installation angle β of the spiral guide vane (4) 3,a is as follows: ； Outer edge inlet liquid flow angle of the spiral guide vane (4) is as follows: ； ； Select the inlet attack angle Δβ of the helical guide vane (4) 3 ; the installation angle of the outer edge inlet of the helical guide vane (4) is: ； In the formula, ω is the rotational speed of the disk (1), with the unit of rad / s; R 2 is the radius of the inner contour line of the arc-shaped flow channel (2-1), with the unit of m.

2. The micro disc pump with a spiral guide vane according to claim 1, Characterized in that, Outer diameter D of the spiral guide vane (4) 4 is equal to the diameter D of the liquid outlet hole (2-3). 2 Equal.

3. The micro disc pump with a spiral guide vane according to claim 1 or 2, Characterized in that, Select coefficient C 1 , coefficient C 1 ranges from 0 < C 1 ≤ 0.2; the inner diameter D of the spiral guide vane (4) 3 is; ； In the formula, D 2 is the diameter of the liquid outlet hole (2-3), with the unit of m.

4. The micro disc pump with a spiral guide vane according to claim 1, Characterized in that, The installation angle β at the inner edge outlet of the spiral guide vane (4) 4,a and the installation angle β at the outer edge outlet of the spiral guide vane (4) 4,b are both equal to 90 degrees.

5. The micro disc pump with a spiral guide vane according to claim 3, Characterized in that, Select coefficient C 2 , the pitch S of the spiral guide vane (4) is: ； In the formula, the coefficient C 2 has a value range of 1 ≤ C 2 ≤ 5, where π is the ratio of a circle's circumference to its diameter, and D 2 is the diameter of the liquid outlet hole (2 - 3), with the unit of m.

6. The micro disc pump with a spiral guide vane according to claim 5, Characterized in that, Select coefficient C 3 , the length L of the spiral guide vane (4) is: ； In the formula, the coefficient C 3 has a value range of 1 ≤ C 3 ≤ 10, where S is the pitch S of the spiral guide vane (4), and the unit is m.

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