Theoretical calculation and experimental verification of peristaltic pump flow

Abstract

According to the method, the defects in the prior art are overcome, theoretical calculation and experimental verification of the flow of the peristaltic pump are provided, due to the fact that no empirical correction coefficient exists, calculation of the flow is completely determined by parameters of a product structure, the method can be applied to multiple peristaltic pump products, and in the same product, the flow can be accurately calculated. If the specification or the material of the pump pipe changes, only corresponding parameters need to be changed during calculation, high theoretical flow calculation precision can be obtained, and the calculation error is controlled within 10%; the invention can be widely applied to the field of peristaltic pumps.

Description

Technical Field

[0001] The present invention relates to the theoretical calculation and experimental verification of the flow rate of a peristaltic pump, belonging to the technical field of peristaltic pumps. Background Art

[0002] A peristaltic pump is a type of transport pump that conveys fluid by means of rotating rollers that cause the pump tube to peristalsis. Due to its characteristics such as the pollution-free nature of the conveyed fluid and its adaptability to gas-liquid two-phase fluids, it is one of the important components for fluid transportation in space stations. When a peristaltic pump operates, the fluid being conveyed can only flow within the pump tube and does not come into contact with other parts of the pump body, thus avoiding the contamination of the fluid by the pump body or the contamination of the pump body by the fluid. In addition to the space station environment, peristaltic pumps are also widely used in industries such as pharmaceuticals, food processing, chemical industry, agriculture, and water treatment.

[0003] Flow rate is one of the key performance indicators of a peristaltic pump. There is a difference between its theoretical calculated value and the experimental value. Experienced peristaltic pump designers can consider this difference and make corrections during the initial design based on their rich experience to make the actual flow rate meet the expected requirements.

[0004] In current related research, the journal paper "Theoretical Calculation and Experimental Verification of the Flow Rate of Peristaltic Pumps" in Chemical Industry Automation and Instrumentation uses the accumulation method to sum up the volume inside the peristaltic pump tube to obtain the flow rate of the peristaltic pump, but ignores the volume occupied when the rollers of the peristaltic pump squeeze the hose, and the calculation accuracy is about 66%.

[0005] Patent CN111209688A uses 3D software modeling to obtain the volume occupied by the roller extrusion, making the calculation accuracy close to 80%, but this method has a certain complexity and low universality.

[0006] Patent CN119475620A uses SOLIDWORKS drawing software to obtain the volume occupied by the roller extrusion, and the calculation accuracy is close to 90%, but this method uses the drawing software to draw, making the calculation process relatively complex. Summary of the Invention

[0007] The present invention overcomes the deficiencies of the prior art and provides a theoretical calculation and experimental verification of the flow rate of a peristaltic pump. When the pump tube specifications or materials change, only the corresponding parameters need to be changed during the calculation to obtain a high theoretical flow rate calculation accuracy and control the calculation error within 10%.

[0008] To solve the above technical problems, the technical solution adopted by the present invention is as follows: A theoretical calculation of the flow rate of a peristaltic pump includes the following steps: Step 1: Measure the following geometric parameters of the peristaltic pump: the inner radius R of the pump housing D , the outer rotation radius r of the rotor rw , the radius r of the rotor r, the outer diameter D of the pump tube, the inner diameter d of the pump tube, the number of rotors N, and the rotational speed n of the pump head; Step 2: The circular cross-sectional area of the pump tube is

[0009] Step 3: The length of the pump tube between two adjacent rotors is ; Step 4: In order to consider the volume occupied by the rotor squeezing the pump tube, the length of the pump tube occupied when a single rotor squeezes the pump tube is calculated as:

[0010] Step 5: The volume of the fluid stored in the pump tube between two adjacent rotors is calculated as:

[0011] Step 6: The displacement of the peristaltic pump rotating one circle is the product of the volume of the fluid stored between two adjacent rotors and the number of rotors. The output displacement of the peristaltic pump rotating one circle is calculated as:

[0012] Step 7: Measure the rotational speed n of the peristaltic pump; Step 8: The flow rate of the peristaltic pump is the product of the displacement of one rotation and the rotational speed. The flow rate of the peristaltic pump is calculated as:

[0013] The present invention relates to an experimental verification of the theoretical calculation of the flow rate of a peristaltic pump, and the test verification is carried out in the following manner: a. Select multiple different peristaltic pumps with the same pump tube material, measure the actual flow rate of each pump respectively, and calculate the theoretical flow rate and error under the corresponding working conditions of each pump; b. Select the same peristaltic pump with the same pump tube specification but different materials, measure the actual flow rate at different rotational speeds, and calculate the theoretical flow rate and error under the corresponding working conditions of the pump; c. Select the same peristaltic pump with different pump tube specifications, measure the actual flow rate of the pump when different pump tubes are used respectively at the same rotational speed, and calculate the theoretical flow rate and error under the corresponding working conditions of the pump; Through the above verification, the present application can be used for multiple peristaltic pump products. In the same product, if the pump tube specification or material changes, only the corresponding parameters need to be changed during calculation, and a higher theoretical flow rate calculation accuracy can be obtained, and the calculation error can be controlled within 10%.

[0014] The beneficial effects of the present invention compared with the prior art are: The present application can be used for multiple peristaltic pump products. In the same product, if the pump tube specification or material changes, only the corresponding parameters need to be changed during calculation, and a higher theoretical flow rate calculation accuracy can be obtained, and the calculation error can be controlled within 10%. Description of the Drawings

[0015] The present invention will be further described below with reference to the accompanying drawings.

[0016] Figure 1 Schematic diagram of the measurement mark for the present invention Figure 1 。

[0017] Figure 2 Schematic diagram of the measurement mark for the present invention Figure 2 。

[0018] Figure 3 Schematic diagram of the measurement mark for the present invention Figure 3 。 Specific embodiments

[0019] The present invention will be further elaborated below with reference to specific embodiments.

[0020] 1. Theoretical calculation process: The theoretical calculation of the flow rate of a peristaltic pump according to the present invention includes the following steps: Step 1: Measure the following geometric parameters of the peristaltic pump: the inner radius R of the pump housing D , the outer rotation radius r of the rotor rw , the radius r of the rotor r , the outer diameter D of the pump tube, the inner diameter d of the pump tube, the number of rotors N, and the rotational speed n of the pump head; Step 2: The circular cross-sectional area of the pump tube is

[0021] Step 3: The length of the pump tube between two adjacent rotors is ; Step 4: In order to consider the volume occupied by the rotor squeezing the pump tube, calculate the length of the pump tube occupied when a single rotor squeezes the pump tube as:

[0022] Step 5: Calculate the volume of fluid stored in the pump tube between two adjacent rotors as:

[0023] Step 6: The displacement of the peristaltic pump in one rotation is the product of the volume of fluid stored between two adjacent rotors and the number of rotors. Calculate the displacement output by the peristaltic pump in one rotation:

[0024] Step 7: Measure the rotational speed n of the peristaltic pump; Step 8: The flow rate of the peristaltic pump is the product of the displacement in one rotation and the rotational speed. Calculate the flow rate of the peristaltic pump:

[0025] 2. Test verification process: As shown in Figure 1 , Figure 2 and Figure 3 shown in the figure: R D is the inner radius of the pump housing; mm; r rw is the outer rotation radius of the rotor; mm; r r is the radius of the rotor; mm; D is the outer diameter of the pump pipe; mm; d is the inner diameter of the pump pipe; mm; n is the rotational speed of the pump head; rpm; N is the number of rotors; pieces; L 1 is the length of the pump pipe between two adjacent rotors; mm; L 2 is the length of the pump pipe occupied when a single rotor extrudes the pump pipe; mm; O 1 is the symbol of the pump head axis; O 2 is the symbol of the rotor axis; Calculate the volume occupied by a single rotor when extruding the pump pipe. (1) First, calculate the length of the pump pipe occupied when a single rotor extrudes the pump pipe. The calculation method is as follows: Draw auxiliary circles along the center line of the pump pipe and the outer wall of the pump pipe (near the axis side) respectively. Connect the pump head axis O 1 and the rotor center O 2 to make an auxiliary line. This auxiliary line intersects the auxiliary circle of the outer wall of the pump pipe (near the axis side) at point C and the auxiliary circle of the center line of the pump pipe at point D. Draw a tangent line to the auxiliary circle of the outer wall of the pump pipe (near the axis side) through point C. This tangent line intersects the outer circle of the rotor at points A and B. Connect O 1 A and O 1 B, O 2 A and O 2 B. Draw a tangent line to the auxiliary circle of the center line of the pump pipe through point D, and intersect the extension lines of O 1 A and O 1 B at E and F respectively. Take the line segment EF (denoted as L 2 ) as approximately the length of the pump pipe occupied when a single rotor extrudes the pump pipe. The calculation method of L 2 is as follows:

[0026] (2) Calculate the circular cross-sectional area of the pump pipe as:

[0027] (3) The volume occupied by a single rotor when extruding the pump pipe is:

[0028] 1) Select 5 peristaltic pumps of Kamoer. The pump tubes are all made of BPT material. Measure the actual flow rate of each pump, and calculate the theoretical flow rate and error under the corresponding working conditions of each pump. The specific data are shown in Table 1.

[0029] As can be seen from Table 1, this application is applied to multiple types of peristaltic pumps. Compared with the actual flow rate, the calculation error can be controlled within 10%.

[0030] 2) Select the Kamoer KPAS100 peristaltic pump. The pump tube specifications are all 2.4mm * 5.6mm. Measure the actual flow rate of the pump when using pump tubes of two materials, BPT and silicone, at different rotation speeds, and calculate the theoretical flow rate and error under the corresponding working conditions of the pump. The specific data are shown in Table 2.

[0031] Since the BPT tube material has better resilience and higher hardness than the silicone tube, the experimental flow rate value corresponding to the BPT tube is closer to the theoretical value. For the pump tubes of both materials, the calculation error value of the present invention is controlled within 10%.

[0032] 3) Select the Kamoer KPAS100 peristaltic pump. The pump tube specifications are 1.6mm * 4.8mm, 2.4mm * 5.6mm, and 3.2mm * 6.4mm respectively, and the rotation speed is 200 rpm. Measure the actual flow rate of the pump when using different pump tubes, and calculate the theoretical flow rate and error under the corresponding working conditions of the pump. The specific data are shown in Table 3.

[0033] Since this application does not have any empirical correction coefficients, the calculation of the flow rate is completely determined by the parameters of the product structure. As can be seen from Tables 1 - 3, this application can be applied to multiple peristaltic pump products. In the same product, if the pump tube specifications or materials change, only the corresponding parameters need to be changed during calculation to obtain a higher theoretical flow rate calculation accuracy and control the calculation error within 10%.

[0034] The present invention has been described in detail above in conjunction with the embodiments. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the gist of the present invention.

Claims

1. A theoretical calculation of peristaltic pump flow, characterized in that: The following steps are involved: Step 1: Measure the following geometric parameters of the peristaltic pump: the inner radius R of the pump casing D , rotor outer rotation radius r rw , rotor radius r r , pump tube outer diameter D, pump tube inner diameter d, number of rotors N, pump head speed n; Step 2: The circular cross-sectional area of ​​the pump tube is Step 3: The length of the pump pipe between two adjacent rotors is ; Step 4: In order to consider the volume occupied by the rotor squeezing the pump tube, calculate the length of the pump tube occupied by a single rotor squeezing the pump tube: Step 5: Calculate the volume of fluid stored in the pump tube between two adjacent rotors: Step 6: The displacement of the peristaltic pump for one rotation is the product of the volume of the fluid stored between two adjacent rotors and the number of rotors. Calculate the output displacement of the peristaltic pump for one rotation: Step 7: Measure the peristaltic pump speed n; Step 8: The peristaltic pump flow rate is the product of the displacement per rotation and the speed. Calculate the peristaltic pump flow rate:

2. An experimental verification of a theoretical calculation of a peristaltic pump flow rate as claimed in claim 1, characterized in that: Perform the test verification as follows: a. Select multiple different peristaltic pumps with the same pump tube material, measure the actual flow rate of each pump respectively, and calculate the theoretical flow rate and error of each pump under the corresponding working conditions; b. Select the same peristaltic pump with the same pump tube specifications but different materials, measure the actual flow rate at different speeds, and calculate the theoretical flow rate and error under the corresponding working conditions of the pump; c. Select the same peristaltic pump with different pump tube specifications, measure the actual flow rate of the pump when using different pump tubes at the same speed, and calculate the theoretical flow rate and error of the pump under the corresponding working conditions; Through the above verification, this application can be used for multiple peristaltic pump products. In the same product, if the pump tube specifications or materials change, only the corresponding parameters need to be changed during calculation to obtain a higher theoretical flow calculation accuracy and control the calculation error within 10%.

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