Bowel sound modeling method, electronic device and medium based on bowel sound generation mechanism

Abstract

The present invention discloses a bowel sound modeling method, electronic device and medium based on the bowel sound sound generation mechanism, the method comprising: S1, obtaining an intestinal flow field simulation result; S2, importing the intestinal flow field simulation result as a sound source into a sound field model for sound field simulation, collecting a bowel sound simulation signal at a collection point, performing spectrum analysis on the bowel sound simulation signal, and verifying the authenticity of the bowel sound simulation signal; S3, comparing the time-frequency domain feature information of the bowel sound simulation signal and the real bowel sound signal, adjusting the sound field model according to the comparison result, and performing sound field simulation again. It establishes the intrinsic connection between the internal structure of the intestine, the peristaltic state of the intestine and the generation of bowel sounds, so as to improve the interpretability of the bowel sound simulation signal.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical models, and in particular relates to a bowel sound modeling method, electronic equipment and medium based on the bowel sound sound generation mechanism. Background Art

[0002] When the intestine moves, the gas and liquid in the intestinal cavity flow with it, producing an intermittent sound of gas passing through water (or gurgling sound) called bowel sounds. The auscultatory study of bowel sounds has great clinical significance, but the actual bowel sound research is often limited by the acquisition of bowel sound signals. On the one hand, the bowel sound signal itself is non-periodic and highly random, subject to large noise interference, weak signal, large individual differences, and the accuracy of the collected bowel sound signal is limited; on the other hand, in order to achieve a more ideal analysis effect, long-term acoustic monitoring is often required, and bowel sound signals are continuously recorded for several hours, which causes great fatigue and distress to the subjects. Therefore, a digital model of bowel sounds is needed to generate a high-precision and long-duration bowel sound signal for subsequent bowel sound analysis research.

[0003] The existing digital model of bowel sounds models different types of bowel sounds by classifying bowel sounds and setting parameter values ​​related to intestinal movement, so as to approximate the time domain waveform and frequency domain characteristics of bowel sound signals. The algorithm of this model is simple and the simulation bowel sound signal has high accuracy, but the establishment of the model is not related to the structural characteristics of the intestine, and the correlation with intestinal movement is low, and the interpretability of the generated bowel sound signal is poor. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a bowel sound modeling method, electronic device and medium based on the bowel sound generation mechanism, establishes the intrinsic connection between the internal structure of the intestine, the peristalsis state of the intestine and the generation of bowel sounds, so as to improve the interpretability of the bowel sound simulation signal.

[0005] The technical solution adopted by the present invention is:

[0006] In a first aspect, the present application discloses a bowel sound modeling method based on the bowel sound production mechanism, comprising:

[0007] S1. Obtain intestinal flow field simulation results;

[0008] S2, importing the intestinal flow field simulation result as a sound source into the sound field model to perform sound field simulation, collecting a bowel sound simulation signal at a collection point, performing spectrum analysis on the bowel sound simulation signal, and verifying the authenticity of the bowel sound simulation signal;

[0009] S3. Compare the time-frequency domain feature information of the simulated bowel sound signal and the real bowel sound signal, adjust the sound field model according to the comparison result, and perform the sound field simulation again.

[0010] As an optional technical solution, the sound field simulation in step S2 includes:

[0011] S21. Open the acoustic model in the Fluent module of Ansys software, select the FW-H acoustic analogy method, set the noise source to the fluid-solid coupling interface, and set the monitoring points;

[0012] S22, obtaining the acoustic signal and spectrum diagram of the monitoring point;

[0013] S23. Verify the results to evaluate the bowel sound simulation signal; wherein the parameter indicators during the evaluation include time-frequency domain characteristic information of the bowel sounds, the time-frequency domain characteristic information includes the duration of the bowel sounds, the main frequency components of the bowel sounds, and the types of bowel sounds, the types including single bursts, multiple bursts, continuous random sounds, and harmonic sounds.

[0014] As an optional technical solution, adjusting the sound field model according to the comparison result in step S3 includes:

[0015] comparing the frequency components of the simulated bowel sound signal with the frequency components of the real bowel sound signal;

[0016] If one of the comparison results is that the frequency of the simulated bowel sound signal is lower than the frequency of the real bowel sound signal as a whole, the simulated segmented contraction period is shortened and the periodic displacement constraint frequency is increased;

[0017] If the second comparison result is that the amplitude spectrum of the simulated bowel sound signal is lower than the amplitude spectrum of the real bowel sound signal as a whole, then the displacement constraint amplitude is increased, the liquid phase inlet velocity is increased, and the intestinal wall simulation material is changed to increase the overall energy of the simulated bowel sound signal to improve the amplitude spectrum of the simulated bowel sound signal.

[0018] As an optional technical solution, the step of obtaining the intestinal flow field simulation result in step S1 includes:

[0019] S11, establishing a three-dimensional geometric model of the human intestine and performing preprocessing;

[0020] S12, dividing the preprocessed three-dimensional geometric model of the intestine into a fluid domain and a solid domain and performing mesh division on each domain;

[0021] S13, setting up fluid domain simulation: importing the intestinal 3D geometric model of the fluid domain after meshing into the Fluent module, simulating the gas-liquid two-phase flow content, and setting model parameters;

[0022] S14. Perform solid domain simulation settings: import the three-dimensional geometric model of the intestine in the solid domain after meshing into the Transient Structural module, set the intestinal wall material parameters, and simulate intestinal movement;

[0023] S15. Perform bidirectional fluid-solid coupling through the System Coupling module, establish data transmission between the fluid domain and the solid domain, simulate the intestinal flow field, and obtain the intestinal process simulation results;

[0024] Among them, the Fluent module, Transient Structural module and System Coupling module are all corresponding functional modules of Ansys software.

[0025] As an optional technical solution, in step S11, the three-dimensional geometric model of the intestine is obtained through an open source database of digital phantoms; and the preprocessing includes format conversion and model simplification operations on the three-dimensional geometric model of the intestine.

[0026] As an optional technical solution, in step S12, the grid division includes:

[0027] S121. In the Design Modeler module of Ansys software, the intestinal wall, i.e., the solid domain, is modeled by establishing a surface and performing surface flipping;

[0028] S122. Suppress the solid domain, name and set the inlet, outlet, and fluid-solid coupling interface of the fluid domain, and perform meshing of the fluid domain;

[0029] S123. Suppress the fluid domain, name the fluid-solid coupling interface for the solid domain, set the corresponding thickness and material parameters for the solid domain to simulate the real intestinal wall, and perform meshing of the solid domain.

[0030] As an optional technical solution, in step S13, the fluid domain simulation setting includes:

[0031] S131. Define the material properties of the gas-liquid two-phase contents. The gas phase uses the software air model, the liquid phase uses the custom material density and viscosity, and the contents are set to incompressible fluids.

[0032] S132. According to the real physiological model of the intestine, define the turbulence model and the multiphase flow model, select the main phase and the secondary phase, and set the model parameters;

[0033] S133, set initial conditions and boundary conditions, define the inlet condition as velocity inlet, the inlet enters the liquid phase with a volume fraction of 1; the outlet condition is pressure outlet; set the unit mark area, the area is initialized to the liquid phase with a volume fraction of 1, and the rest of the intestinal area is initialized to the gas phase with a volume fraction of 1;

[0034] S134. Set a dynamic grid and define the dynamic grid method of the fluid-solid coupling interface as system coupling to achieve the subsequent transfer of fluid-solid coupling data from the fluid domain to the solid domain.

[0035] As an optional technical solution, in step S14, the solid domain simulation setting includes:

[0036] S141, setting displacement boundary conditions to simulate the segmental contraction movement of the intestine;

[0037] S142. Set up simple support to restrict intestinal movement and deformation;

[0038] S143. Setting a fluid-solid coupling interface to achieve the subsequent transfer of fluid-solid coupling data from the solid domain to the fluid domain.

[0039] In a second aspect, the present application discloses an electronic device comprising: one or more processors; one or more memories; the one or more memories storing one or more computer programs, the one or more computer programs comprising instructions, which, when executed by the one or more processors, enable the electronic device to perform the method in the first aspect described above.

[0040] In a third aspect, the present application discloses a computer-readable medium, comprising a computer program. When the computer program is executed on a computer, the computer is caused to execute the method in the first aspect.

[0041] The beneficial effects of the present invention are:

[0042] 1. Starting from the sound mechanism of bowel sounds and the modeling of intestinal physiological structure, the generation of bowel sounds is linked to intestinal movement, especially the interaction between the intestine and intestinal contents, to obtain a highly interpretable bowel sound simulation signal, which is convenient for subsequent bowel sound analysis and research.

[0043] 2. By adjusting the model parameter settings, the bowel sound signals under different physiological or pathological conditions of the intestine can be simulated to provide more explanatory data support for analyzing intestinal motility, the intrinsic relationship between the state of intestinal contents and bowel sounds, and subsequent bowel sound calculation and analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 4 is a flow chart of a method for modeling bowel sounds based on the mechanism of bowel sound production in an embodiment.

[0045] Figure 2 is a schematic diagram of a colon module selected from BodyParts3D in the embodiment.

[0046] Figure 3 It is a schematic diagram of the selected colon module after preprocessing in the embodiment.

[0047] Figure 4 Schematic diagram of the fluid domain meshing result in the embodiment.

[0048] Figure 5 Schematic diagram of the solid domain meshing result in the embodiment.

[0049] Figure 6 This is the unit marking area in the embodiment of the present invention, that is, the initial liquid chyme distribution map in the colon.

[0050] Figure 7 This is a cloud diagram of the gas phase volume fraction after the fluid domain is initialized in an embodiment of the present invention.

[0051] Figure 8 This is a diagram of the parameter settings of the solid domain simulation segmented contraction software in an embodiment of the present invention.

[0052] Fig. 9 This is a diagram of the simple support constraint setting for the solid domain in an embodiment of the present invention.

[0053] Fig.10 This is a diagram of the acoustic simulation monitoring point settings in an embodiment of the present invention.

[0054] Fig.11 Schematic diagram of acoustic signal at monitoring point 2 in an embodiment of the present invention.

[0055] Fig.12 This is the FFT spectrum diagram of the acoustic signal at monitoring point 2 in an embodiment of the present invention. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The steps and modules of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0057] Example

[0058] like Figure 1 As shown, this embodiment discloses a bowel sound modeling method based on the bowel sound generation mechanism, including:

[0059] S1. Obtain intestinal flow field simulation results;

[0060] S2, importing the intestinal flow field simulation result as a sound source into the sound field model to perform sound field simulation, collecting a bowel sound simulation signal at a collection point, performing spectrum analysis on the bowel sound simulation signal, and verifying the authenticity of the bowel sound simulation signal;

[0061] S3. Compare the time-frequency domain feature information of the simulated bowel sound signal and the real bowel sound signal, adjust the sound field model according to the comparison result, and perform the sound field simulation again.

[0062] As an optional implementation, the sound field simulation in step S2 includes:

[0063] S21. Open the acoustic model in the Fluent module of Ansys software, select the FW-H acoustic analogy method, set the noise source to the fluid-solid coupling interface, and set the monitoring points;

[0064] S22, obtaining the acoustic signal and spectrum diagram of the monitoring point;

[0065] S23. Verify the results to evaluate the bowel sound simulation signal; wherein the parameter indicators during the evaluation include time-frequency domain characteristic information of the bowel sounds, the time-frequency domain characteristic information includes the duration of the bowel sounds, the main frequency components of the bowel sounds, and the types of bowel sounds, the types including single bursts, multiple bursts, continuous random sounds, and harmonic sounds.

[0066] As an optional implementation, adjusting the sound field model according to the comparison result in step S3 includes:

[0067] comparing the frequency components of the simulated bowel sound signal with the frequency components of the real bowel sound signal;

[0068] If one of the comparison results is that the frequency of the simulated bowel sound signal is lower than the frequency of the real bowel sound signal as a whole, the simulated segmented contraction period is shortened and the periodic displacement constraint frequency is increased;

[0069] If the second comparison result is that the amplitude spectrum of the simulated bowel sound signal is lower than the amplitude spectrum of the real bowel sound signal as a whole, then the displacement constraint amplitude is increased, the liquid phase inlet velocity is increased, and the intestinal wall simulation material is changed to increase the overall energy of the simulated bowel sound signal to improve the amplitude spectrum of the simulated bowel sound signal.

[0070] As an optional implementation, the step S1 of obtaining the intestinal flow field simulation result includes:

[0071] S11, establishing a three-dimensional geometric model of the human intestine and performing preprocessing;

[0072] S12, dividing the preprocessed three-dimensional geometric model of the intestine into a fluid domain and a solid domain and performing mesh division on each domain;

[0073] S13, setting up fluid domain simulation: importing the intestinal 3D geometric model of the fluid domain after meshing into the Fluent module, simulating the gas-liquid two-phase flow content, and setting model parameters;

[0074] S14. Perform solid domain simulation settings: import the three-dimensional geometric model of the intestine in the solid domain after meshing into the Transient Structural module, set the intestinal wall material parameters, and simulate intestinal movement;

[0075] S15. Perform bidirectional fluid-solid coupling through the System Coupling module, establish data transmission between the fluid domain and the solid domain, simulate the intestinal flow field, and obtain the intestinal process simulation results;

[0076] Among them, the Fluent module, Transient Structural module and System Coupling module are all corresponding functional modules of Ansys software.

[0077] As an optional implementation, in step S11, the three-dimensional geometric model of the intestine is obtained through an open source database of digital phantoms; and the preprocessing includes format conversion and model simplification operations on the three-dimensional geometric model of the intestine.

[0078] As an optional implementation, in step S12, the grid division includes:

[0079] S121. In the Design Modeler module of Ansys software, the intestinal wall, i.e., the solid domain, is modeled by establishing a surface and performing surface flipping;

[0080] S122. Suppress the solid domain, name and set the inlet, outlet, and fluid-solid coupling interface of the fluid domain, and perform meshing of the fluid domain;

[0081] S123. Suppress the fluid domain, name the fluid-solid coupling interface for the solid domain, set the corresponding thickness and material parameters for the solid domain to simulate the real intestinal wall, and perform meshing of the solid domain.

[0082] As an optional implementation, in step S13, the fluid domain simulation setting includes:

[0083] S131. Define the material properties of the gas-liquid two-phase contents. The gas phase uses the software air model, the liquid phase uses the custom material density and viscosity, and the contents are set to incompressible fluids.

[0084] S132. According to the real physiological model of the intestine, define the turbulence model and the multiphase flow model, select the main phase and the secondary phase, and set the model parameters;

[0085] S133, set initial conditions and boundary conditions, define the inlet condition as velocity inlet, the inlet enters the liquid phase with a volume fraction of 1; the outlet condition is pressure outlet; set the unit mark area, the area is initialized to the liquid phase with a volume fraction of 1, and the rest of the intestinal area is initialized to the gas phase with a volume fraction of 1;

[0086] S134. Set a dynamic grid and define the dynamic grid method of the fluid-solid coupling interface as system coupling to achieve the subsequent transfer of fluid-solid coupling data from the fluid domain to the solid domain.

[0087] As an optional implementation, in step S14, the solid domain simulation setting includes:

[0088] S141, setting displacement boundary conditions to simulate the segmental contraction movement of the intestine;

[0089] S142. Set up simple support to restrict intestinal movement and deformation;

[0090] S143. Setting a fluid-solid coupling interface to achieve the subsequent transfer of fluid-solid coupling data from the solid domain to the fluid domain.

[0091] In order to better understand the present application, the method of this embodiment is further described below.

[0092] The method for digital modeling of bowel sounds based on the bowel sound generation mechanism of this embodiment can be roughly divided into the following processes:

[0093] 1. Obtain intestinal flow field simulation results.

[0094] 1.1. Establish a three-dimensional geometric model of the human intestine and perform preprocessing to meet the requirements of subsequent simulation processing.

[0095] Specifically, Figure 2 As shown, in this embodiment, the colon module of BodyParts3D is selected for analysis, and the selected colon module is preprocessed to obtain the following Figure 3 For the structure shown, the preprocessing includes shrinking the geometry and smoothing in the Space Claim module of Ansys software to simplify the intestinal geometry, and converting from the OBJ file format to the CAD solid structure format through Auto Skin. Figure 3 In the above code, inlet is the entrance and outlet is the exit.

[0096] 1.2. Divide the three-dimensional geometric model of the intestine into fluid domain and solid domain and perform mesh division separately.

[0097] Specifically, the steps include:

[0098] 1.2.1. In the Design Modeler module of Ansys software, the intestinal wall, i.e., the solid domain, is modeled by establishing a surface and performing surface flipping. Among them, establishing a surface is a built-in method of Ansys software.

[0099] 1.2.2. Import the model processed in step 1.2.1 into the Meshing module of Ansys software, suppress the solid domain, select the surface of the fluid domain to name the inlet, outlet, and fluid-solid coupling interface, select the tetrahedron method for meshing, and use Fluent as the solver. The final number of mesh units is 691442, and the mesh unit quality reaches 0.83415. The meshing results of the fluid domain are as follows: Figure 4 shown.

[0100] 1.2.3. Import the model processed in step 1.2.1 into the Transient Structural module of Ansys software, suppress the fluid domain, and name the fluid-solid coupling interface of the solid domain. To simulate the real intestinal wall effect, set the thickness of the solid domain, i.e. the intestinal wall, to 0.01m, and set the intestinal wall material to linear elastic material in the engineering material, with a material density of 2000kg / m 3 , Poisson's ratio is 0.48, and elastic modulus is 10MPa. The triangle method is used for meshing, the solver is Notlinear Machanical, and the number of mesh elements is 4465, the unit quality is 0.96148, and the solid domain meshing results are as follows Figure 5 shown.

[0101] 1.3 Fluid domain simulation settings: Import the three-dimensional geometric model of the intestine in the fluid domain after meshing into the Fluent module, simulate the gas-liquid two-phase flow content, and set the model parameters.

[0102] Specifically, the steps include:

[0103] 1.3.1. Define the material properties of gas-liquid two-phase contents: Intestinal contents include undigested food residues, water, bacteria, digestive juices, gases, etc. This embodiment defines intestinal contents as gas-liquid two-phase flow based on the contribution to bowel sounds and modeling complexity. At the same time, since the speed of intestinal contents is much lower than the speed of sound, it belongs to a low Mach number flow. Under this condition, the density and viscosity of the fluid remain unchanged, and it is an incompressible fluid. Therefore, for the material parameter setting of gas-liquid two-phase contents, the gas phase model uses the air model in the Ansys Fluent module material library, and the material parameters are: density is 1.225 kg / m 3 , the viscosity is 1.7894 × 10 -5kg / (m·s), liquid phase selects custom material density and viscosity, density is 1000kg / m 3 , the viscosity is 0.005kg / (m·s).

[0104] 1.3.2. Define turbulence model and multiphase flow model: This embodiment aims to simulate the flow field and acoustic field of the colon for a period of time after a meal. The corresponding flow field model is: the chyme enters the colon cavity filled with air and containing a certain volume of chyme under the push of peristalsis. Combined with the content flow mentioned in step 1.3.1 as an incompressible fluid, the multiphase flow model uses the VOF model, with 2 phases, in which the main phase is set as the gas phase, the secondary phase is set as the liquid phase, the two-phase interaction is set as the surface tension model, and the surface tension coefficient is set to 0.075; due to the low velocity of the intestinal contents, the Reynolds number of the content flow is low, so the turbulence model is selected as the RNG k-ε turbulence model.

[0105] 1.3.3. Set initial conditions and boundary conditions: According to the flow field model of this embodiment mentioned in step 1.3.2, define the inlet condition as velocity inlet, the inlet enters the liquid phase with a volume fraction of 1, and the velocity is 0.015m / s, simulating the chyme entering the colon under the action of peristalsis; the outlet condition is pressure outlet, and the outlet pressure is 0Pa; set the unit mark area, and the area is initialized to the liquid phase with a volume fraction of 1, simulating the retained chyme at the bottom of the colon before the inlet chyme enters. The area is set as follows Figure 6 As shown; the rest of the area is initialized to a gas phase with a volume fraction of 1. After initialization, the gas volume fraction is as follows Figure 7 As shown;

[0106] 1.3.4. Set dynamic mesh: Define the dynamic mesh method of the fluid-solid coupling interface as system coupling, which is achieved through smoothing and re-meshing. Smoothing refers to a technical method that optimizes the position of mesh nodes during mesh deformation to make mesh deformation smoother, avoid inappropriate mesh distortion, and maintain mesh quality and geometric structure stability.

[0107] 1.4. Solid domain simulation settings: Import the three-dimensional geometric model of the intestine in the solid domain after meshing into the Transient Structural module, set the intestinal wall material parameters, and simulate intestinal movement.

[0108] Specifically, the steps include:

[0109] 1.4.1. Set displacement boundary conditions to simulate segmental contraction of the intestine. According to step 1.3.2, this embodiment simulates the flow field and sound field in the colon for a period of time after a meal. For a period of time after a meal, segmental contraction is active, which can achieve full mixing of the contents and make a huge contribution to the generation of bowel sounds. Therefore, this embodiment is set to simulate segmented contraction with a contraction period of 4s, a contraction wavelength of 0.07m, and a contraction amplitude of 0.001m. This is achieved in the Transient Mechanical module by imposing displacement boundary condition constraints on the wall. The specific settings are as follows: Figure 8 As shown;

[0110] 1.4.2, such as Fig. 9 As shown in the figure, simple supports are set to constrain the deformation of intestinal movement. Setting simple supports is a built-in method of Ansys software.

[0111] 1.4.3. Set up the fluid-structure coupling interface to realize data transfer.

[0112] 1.5. Use the System Coupling module to perform bidirectional fluid-solid coupling, establish data transmission between the fluid domain and the solid domain, and simulate the intestinal flow field.

[0113] Specifically, the fluid domain transmits the pressure data to the solid domain, and the solid domain transmits the interface node displacement information to the fluid domain. The end time is set to 4s, the time step is 0.0005s, the minimum number of iterations is 1, and the maximum number of iterations is 5, thereby realizing bidirectional fluid-solid coupling simulation and obtaining the intestinal process simulation results.

[0114] 1.6. Import the intestinal process simulation results obtained in step 1.5 as the sound source into the sound field model for sound field simulation, obtain the bowel sound simulation signal at the collection point, perform spectrum analysis on the bowel sound simulation signal, and verify the authenticity of the bowel sound simulation signal.

[0115] Specifically, the steps include:

[0116] 1.6.1. Open the acoustic model in the Fluent module of Ansys software, select the FW-H acoustic analogy method, set the noise source to the fluid-solid coupling interface, and set the receiving point (i.e. monitoring point) as follows: Fig.10 shown.

[0117] 1.6.2. After the simulation is completed, obtain the acoustic signal and spectrum of the monitoring point, such as Fig.11 , Fig.12 shown.

[0118] 1.6.3. Verify the results from two aspects: doctor verification and parameter verification, and evaluate the simulated bowel sound signal: Doctor verification is the subjective evaluation of the simulated bowel sound signal by the doctor based on clinical experience. Parameter verification depends on the multi-dimensional characteristics of the time-frequency domain of bowel sounds: Bowel sound signal characteristics such as short duration of bowel sounds, the main frequency components of bowel sounds between 60-1500Hz, and bowel sounds can be classified into four types: single burst, multiple bursts, continuous random sound, and harmonic sound.

[0119] 1.7. Compare the time and frequency domain characteristics of the simulated bowel sound signal with the real bowel sound, modify the model accordingly, and perform sound field simulation again to obtain a more simulated digital bowel sound signal.

[0120] Specifically, Fig.12 As shown in the figure, the low-frequency components of the amplitude spectrum of the simulated bowel sound signal obtained by monitoring point 2 (i.e., receiver-2) are mainly concentrated below 50Hz, with low peaks near 300Hz and 520Hz, and the amplitude value at the 0Hz frequency point, that is, the DC component, is extremely large. Compared with the statistical frequency domain range of 60-1500Hz of the real bowel sound signal, the frequency is lower. Therefore, the simulated segmented contraction cycle is shortened accordingly, and the periodic displacement constraint frequency is increased. In addition, the amplitude spectrum of the simulated signal is lower than the amplitude spectrum of the real signal as a whole. The displacement constraint amplitude is increased, the liquid phase inlet velocity is increased, and the intestinal wall simulation material is changed to increase the overall energy of the simulated signal and improve the amplitude spectrum. The process of performing the sound field simulation again can refer to step 1.6, which will not be repeated here.

[0121] It should be noted that: Figure 7 , Figure 8 , Fig.11 and Fig.12 The "e" that appears in indicates scientific notation, such as Figure 7 1.000e+00 in the equation represents 1×10 0 , 9.000e-01 means 9×10 -1 .

[0122] It should also be noted that: Figure 8 The X in the horizontal coordinate represents the coordinate value of the X-axis direction of the three-dimensional geometric model of the intestine. Figure 8 The horizontal coordinate Z represents the coordinate value of the Z-axis direction of the three-dimensional geometric model of the intestine.

[0123] It should also be noted that: Fig. 9 Simple supports 1-4 in the figure represent simple support operations applied at different positions.

[0124] It should also be noted that: Fig.11 The ordinate is the acoustic pressure, the e in the ordinate is the scientific notation, and the abscissa is the time, in seconds.

[0125] It should also be noted that: Fig.12 The horizontal axis is frequency, the vertical axis is magnitude, and the "e" represents scientific notation.

[0126] In another embodiment, an electronic device is disclosed, including: one or more processors; one or more memories; the one or more memories store one or more computer programs, and the one or more computer programs include instructions, and when the instructions are executed by the one or more processors, the electronic device executes the method in the above embodiment.

[0127] In another embodiment, a computer-readable medium is disclosed, including a computer program. When the computer program is executed on a computer, the computer is enabled to execute the method in the above embodiment.

[0128] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the electronic device and computer-readable medium described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0129] The above description is only a specific implementation mode of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. All technical solutions that fall within the scope defined by the claims of the present invention fall within the protection scope of the present invention.

Claims

1. A bowel sound modeling method based on the bowel sound generation mechanism, characterized in that: include: S1. Obtain intestinal flow field simulation results; S2, importing the intestinal flow field simulation result as a sound source into the sound field model to perform sound field simulation, collecting a bowel sound simulation signal at a collection point, performing spectrum analysis on the bowel sound simulation signal, and verifying the authenticity of the bowel sound simulation signal; S3, comparing the time-frequency domain feature information of the simulated bowel sound signal and the real bowel sound signal, adjusting the sound field model according to the comparison result, and performing the sound field simulation again; The step S1 of obtaining the intestinal flow field simulation results includes: S11. Establish a three-dimensional geometric model of the human intestine and perform preprocessing; S12, dividing the preprocessed three-dimensional geometric model of the intestine into a fluid domain and a solid domain and performing mesh division on each domain; S13, setting up fluid domain simulation: importing the intestinal 3D geometric model of the fluid domain after meshing into the Fluent module, simulating the gas-liquid two-phase flow content, and setting model parameters; S14. Perform solid domain simulation settings: import the three-dimensional geometric model of the intestine in the solid domain after meshing into the Transient Structural module, set the intestinal wall material parameters, and simulate intestinal movement; S15. Perform bidirectional fluid-solid coupling through the System Coupling module, establish data transmission between the fluid domain and the solid domain, simulate the intestinal flow field, and obtain the intestinal process simulation results; Among them, Fluent module, Transient Structural module and System Coupling module are the corresponding functional modules of Ansys software; In step S13, the fluid domain simulation setting includes: S131. Define the material properties of the gas-liquid two-phase contents. The gas phase uses the software air model, the liquid phase uses the custom material density and viscosity, and the contents are set to incompressible fluids. S132. According to the real physiological model of the intestine, define the turbulence model and the multiphase flow model, select the main phase and the secondary phase, and set the model parameters; The sound field simulation in step S2 includes: S21. Open the acoustic model in the Fluent module of Ansys software, select the FW-H acoustic analogy method, set the noise source to the fluid-solid coupling interface, and set the monitoring points; S22, obtaining the acoustic signal and spectrum diagram of the monitoring point; S23, performing result verification to evaluate the bowel sound simulation signal; wherein the parameter indicators during the evaluation include time-frequency domain characteristic information of the bowel sound, the time-frequency domain characteristic information includes the duration of the bowel sound, the main frequency components of the bowel sound, and the type of the bowel sound, the type including single burst, multiple bursts, continuous random sound, and harmonic sound; Adjusting the sound field model according to the comparison result in step S3 includes: comparing the frequency components of the simulated bowel sound signal with the frequency components of the real bowel sound signal; If one of the comparison results is that the frequency of the simulated bowel sound signal is lower than the frequency of the real bowel sound signal as a whole, the simulated segmented contraction period is shortened and the periodic displacement constraint frequency is increased; If the second comparison result is that the amplitude spectrum of the simulated bowel sound signal is lower than the amplitude spectrum of the real bowel sound signal as a whole, then the displacement constraint amplitude is increased, the liquid phase inlet velocity is increased, and the intestinal wall simulation material is changed to increase the overall energy of the simulated bowel sound signal to improve the amplitude spectrum of the simulated bowel sound signal.

2. The bowel sound modeling method based on the bowel sound generation mechanism according to claim 1, characterized in that: In step S11, the three-dimensional geometric model of the intestine is obtained through an open source database of digital phantoms; the preprocessing includes format conversion and model simplification operations on the three-dimensional geometric model of the intestine.

3. The bowel sound modeling method based on the bowel sound generation mechanism according to claim 1, characterized in that: In step S12, the grid division includes: S121. In the Design Modeler module of Ansys software, the intestinal wall, i.e., the solid domain, is modeled by establishing a surface and performing surface flipping; S122. Suppress the solid domain, name and set the inlet, outlet, and fluid-solid coupling interface of the fluid domain, and perform meshing of the fluid domain; S123. Suppress the fluid domain, name the fluid-solid coupling interface for the solid domain, set the corresponding thickness and material parameters for the solid domain to simulate the real intestinal wall, and perform meshing of the solid domain.

4. The bowel sound modeling method based on the bowel sound generation mechanism according to claim 1, characterized in that: In step S13, the fluid domain simulation setting includes: S133, set initial conditions and boundary conditions, define the inlet condition as velocity inlet, the inlet enters the liquid phase with a volume fraction of 1; the outlet condition is pressure outlet; set the unit mark area, the area is initialized to the liquid phase with a volume fraction of 1, and the rest of the intestinal area is initialized to the gas phase with a volume fraction of 1; S134. Set a dynamic grid and define the dynamic grid method of the fluid-solid coupling interface as system coupling to achieve the subsequent transfer of fluid-solid coupling data from the fluid domain to the solid domain.

5. The bowel sound modeling method based on the bowel sound generation mechanism according to claim 1, characterized in that: In step S14, the solid domain simulation setting includes: S141, setting displacement boundary conditions to simulate the segmental contraction movement of the intestine; S142. Set up simple support to restrict intestinal movement and deformation; S143. Setting a fluid-solid coupling interface to achieve the subsequent transfer of fluid-solid coupling data from the solid domain to the fluid domain.

6. An electronic device, characterized in that: include: one or more processors; One or more memories; the one or more memories store one or more computer programs, the one or more computer programs include instructions, when the instructions are executed by the one or more processors, the electronic device executes the method as described in any one of claims 1-5.

7. A computer-readable medium, characterized in that The method comprises a computer program, which, when executed on a computer, causes the computer to execute the method according to any one of claims 1 to 5.

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