22 results about "Viscous dissipation" patented technology

The invention provides a rotating mechanical system performance evaluation and optimization method and system based on system negentropy conversion rate, and the method comprises the following steps: carrying out the numerical simulation of a flow field of a rotating mechanical system through a computational fluid mechanics method, and obtaining the parameters of the flow field; calculating a viscous dissipation entropy yield, a turbulent dissipation entropy yield and a wall entropy yield in the fluid domain based on the flow field parameters; the total entropy yield of the system is obtained through the volume fraction and the wall area fraction of the whole fluid domain; converting the input power of the rotating machinery into an equivalent negentropy flow, and calculating the negentropy conversion rate of the system for evaluating the effective utilization degree of the input power; and evaluating the performance of the rotating machinery system based on the negentropy conversion rate, and identifying a key area of energy loss. According to the method, the negentropy conversion rate result is applied to structural design optimization, running state diagnosis and energy efficiency adjustment of the rotating machinery, and online calculation and dynamic visualization can be realized in combination with real-time monitoring data.

The invention discloses a liquid damping shock absorber which comprises an outer shell (6) and a middle shaft (2) and is characterized in that the outer shell (6) is in a barrel shape, the middle shaft (2) is installed at the bottom of the barrel through an axial supporting mechanism (14), a damping barrel is arranged in the outer shell (6) and installed on the middle shaft (2), and the damping barrel is of a cavity structure with an elastic gap in the lower bottom face. The upper end of the middle shaft (2) penetrates out of the center of an upper end cover (3) of the outer shell (6), damping liquid is contained in the outer shell (6), and the liquid level of the damping liquid is higher than the lower bottom face of the damping cylinder. According to the shock absorber, the damping liquid and the damping cylinder are organically combined, the damping cylinder extrudes the damping liquid when the shock absorber is subjected to an external load, vibration energy is counteracted through viscous dissipation and dynamic pressure generated by liquid shaking, gaps can be changed when pressure is received by the porous structure characteristics of the bottom of the damping cylinder, and the flow of the damping liquid penetrating through the gaps is influenced; therefore, the damping of the shock absorber is variable.

The application discloses a viscoelastic-plastic simulation method based on a Bingham model, and comprises the following steps: obtaining a geometric model, material constitutive parameters and boundary conditions of a target geological body; constructing a complementary energy functional containing a viscous dissipation potential, and converting a Bingham viscoelastic-plastic constitutive relation into a mathematical programming problem constrained by a Drucker-Prager yield criterion; discretizing the geometric model space and introducing a time step, and discretizing the mathematical programming problem into a second-order cone complementary problem with a block-sparse structure, which contains a normalized second-order cone constraint equivalent to the Drucker-Prager criterion; performing smoothing treatment and solving by block elimination using the block-sparse structure to obtain a displacement field and a stress field. The application solves the problem that the existing convex programming solving framework cannot handle viscoelastic-plastic effects by introducing the viscous dissipation potential into the complementary energy functional.

The invention relates to a method for calculating porous medium two-phase flow energy dissipation based on a particle velocity measurement method, and belongs to the technical field of porous medium seepage mechanics experiments. The invention discloses a method for calculating porous medium two-phase flow energy dissipation based on a particle velocity measurement method. The method comprises the following steps: preparing a transparent pore medium microscopic model with a specific microscopic pore structure; carrying out a visual multiphase flow experiment on the pore medium microscopic model; determining external input work based on the inlet and outlet pressure data; accurate calibration of space and phase state is carried out on the original image, and interface energy is obtained through calculation; determining a velocity vector of a non-wetting phase in an experiment based on a particle velocity measurement method, and calculating to obtain kinetic energy; and determining the ratio of energy dissipation to total energy in the multiphase flow system based on external input work, interface energy and kinetic energy. According to the method, the conversion from a visual flow image to a quantitative energy component can be realized, and the viscous dissipation and the interface energy in the displacement process are accurately calculated, so that an energy dissipation mechanism is disclosed, and a key data support is provided for engineering optimization and numerical simulation.

The application discloses a roughened casing wall configuration for suppressing tip clearance cavitation by using the wall attachment effect. The configuration is uniformly arranged on the inner wall of the casing in the circumferential direction and covers the blade tip region in the axial direction. After the leakage jet is formed, the leakage jet will enter the configuration by using the wall attachment effect and form an induced vortex in the configuration to suppress the development of the leakage jet. The configuration is designed by using the flow characteristics of the leakage jet in the gap and the formation mechanism of the tip clearance vortex system, so that the turbulent flow is triggered early in the gap, the viscous dissipation of the leakage jet is increased, and the stable suppression effect is achieved at the source of the vortex system and cavitation.

The invention relates to the technical field of sensors, in particular to a multi-dimensional force sensor which comprises a shell, an elastic body, a supporting structure and a plurality of dampers. The elastic body is arranged in the shell and comprises a load input end for receiving an external load and a mounting part connected with the shell, and the elastic body is used for generating deformation in response to the external load; the supporting structure is arranged on the periphery of the elastic body in a sleeving mode and located in the shell, and the supporting structure is connected with the load input end; the multiple dampers are arranged between the supporting structure and the shell; wherein the damper is configured to dissipate the vibration energy of the elastic body through a viscous dissipation effect or flexible deformation. According to the multi-dimensional force sensor provided by the invention, the dynamic performance can be directly and effectively improved from a mechanical structure, the self vibration is inhibited, and the response time is shortened.

The application discloses a battery pack thermal boundary layer destruction method and a thermal management method based on acoustic streaming effect. The method comprises the following steps: generating an alternating magnetic field outside a box body, penetrating the box body wall to drive the flexible vibration element of the inner wall to generate high-frequency micro-vibration; the vibration radiates acoustic waves in the immersed liquid, and the acoustic streaming effect is generated by utilizing the viscous dissipation of the liquid; the acoustic streaming forms local shear force in the micron boundary layer near the surface of the battery cell, and destroys the thermal boundary layer attached to the surface of the battery cell. The application also provides a thermal management method comprising the method, immersing the battery cell in the insulating cooling liquid, and simultaneously removing the air film by using the acoustic streaming. The application adopts non-contact acoustic streaming disturbance, has no mechanical wear and no sealing damage, can accurately remove the micron-level air film, reduces the interface thermal resistance, and is suitable for the full-life maintenance-free energy storage system.

The invention discloses a pump station equipment management and control early warning system based on the Internet of Things, and relates to the technical field of management and control early warning of pump station equipment based on the Internet of Things. The system comprises a multi-source sensing module which is deployed at a key node of pump station equipment and comprises a plurality of sensors and an acquisition unit; the entropy yield calculation module is used for calculating viscous dissipation, heat conduction dissipation and total entropy yield in real time through an embedded processor; the quantization health index generation module is used for generating health indexes and dividing states; the fault traceability module is used for positioning a damage source based on entropy cloud image gradient analysis; and the early warning execution module triggers a third-level early warning protocol when the conditions are met. The system further comprises a fluid-solid coupling solver and other units, edge computing, cloud scheduling and national cryptographic algorithm encryption are adopted, early warning and accurate traceability of hidden faults of pump station equipment can be achieved, and safe and efficient operation of the equipment is guaranteed.

The invention discloses a conductive polymer ultraviolet aging evaluation method, mainly discusses viscosity and barrier property change characteristics of a stainless steel short fiber reinforced nylon system under ultraviolet aging, and provides a related quantitative analysis method. Through ultraviolet radiation and cyclic compression tests, the influence of aging on viscous dissipation in the compression process is explored. And under cyclic stress, along with the increase of ultraviolet exposure time, the viscous dissipation is reduced in a nearly linear manner. The resistivity and the dimensionless barrier parameter of the material in an unloaded state are linearly reduced along with the prolonging of the ultraviolet radiation time. In order to quantify the ultraviolet aging process, a dimensionless parameter based on the viscosity dissipation change of the polymer under ultraviolet exposure is introduced, a new index is provided for evaluating the aging degree of the material, and meanwhile, a new model is provided for describing the piezoresistive behavior of the conductive polymer composite material under the ultraviolet aging condition.

The invention discloses a combustor full life cycle energy efficiency management platform based on digital twinning, and the platform comprises a real-time sensing unit, a digital twinning body construction unit, a monitoring unit, a collaborative optimization unit, and a track writing unit. The real-time sensing unit synchronously collects heat flux density and temperature gradient data in a combustor based on a sensor array. Then calculating a comprehensive entropy production index generated by heat conduction and viscous dissipation in real time; the digital twinborn body construction unit adopts a physical twinborn channel and a data twinborn channel which are parallel to each other to construct a digital twinborn body, and the two channels are bidirectionally coupled through a parameter interaction layer; the monitoring unit continuously collects the pressure difference value of an inlet and an outlet of the combustor through the differential pressure transmitter and constructs a long-term operation database. According to the method, through multi-dimensional entropy production analysis and a self-adaptive digital twinning architecture, deep expansion of complete-cycle energy efficiency evaluation of the combustor is realized, and the early recognition capability of deep-level energy efficiency degradation is remarkably improved.

The present application relates to a kind of hydraulic efficiency calculation method of water turbine, belong to the technical field of hydraulic machinery and its system.This application includes the following steps:A, determine the three-dimensional flow field region including water turbine, i.e.control body;B, perform fluid dynamics calculation, obtain the three-dimensional steady flow field distribution of each region;C, calculate the viscous dissipation power of fluid in control body;D, calculate the kinetic energy change rate of control body;E, calculate the power done by external surface force to control body;F, calculate the power done by fluid body force of control body;G, calculate the hydraulic efficiency of water turbine.The present application proposes a new kind of quantitative calculation method of hydraulic efficiency of water turbine, with universality.

The invention discloses an additive manufacturing experimental device based on an alternating magnetic field and variable metal droplet sizes. The device is sequentially provided with a laser generator, a protective gas mechanism, a powder / wire feeding mechanism, a coaxial nozzle, molten metal droplets, a workpiece (a molten pool) and a platform for bearing the molten pool which are coaxially arranged. An alternating magnetic field coil and an alternating magnetic field displacement table moving up and down are arranged at the position flush with the surface of the molten pool, and the alternating magnetic field can generate eddy current in the molten pool so as to increase viscous dissipation of flowing in the molten pool, reduce oscillation kinetic energy, avoid formation of unnatural recesses on the surface of the molten pool and reduce splashing; according to the powder / wire feeding mechanism, powder / wires with different diameters are adopted for alternately feeding powder, the mirror symmetry of the same liquid drop size and speed is broken, and convection in a molten pool is enhanced. The magnetic field provides conditions for stable printing under strong airflow, the variable-size liquid drops optimize the microstructure on the basis of stability, and the DED technology is jointly promoted to develop to better performance.

This invention belongs to the field of acoustic noise reduction and sound absorption materials technology, and discloses a thin-film coupled embedded neck cascaded sound absorption structure. The structure includes a top thin-film assembly and a lower embedded neck cascaded resonant cavity. The thin-film assembly includes a support frame and a thin film, which is suspended above the resonant cavity via the support frame, forming an air layer with the top wall of the resonant cavity. The resonant cavity is enclosed by a solid wall with sidewalls, a top wall, a middle partition, and a bottom wall. The middle partition divides it into upper and lower cavities. A first-stage embedded neck tube penetrates the top wall to the first cavity, and a second-stage embedded neck tube penetrates the middle partition and extends into both cavities. This invention combines the characteristics of thin-film vibration and cascaded resonant cavities, achieving broadband and efficient sound energy absorption in a compact space through multiple coupled resonances and viscous dissipation mechanisms. It significantly improves mid-to-low frequency sound absorption performance and is suitable for noise reduction in building, transportation, and industrial applications.

The application belongs to the field of fluid mechanics, and particularly relates to a pipeline system pressure fluctuation physical mechanism simulation method and system, which comprises a pipeline topology structure accurate modeling step, adopts a parameterized modeling method and a graph theory organization strategy to perform standardized modeling on pipeline accessories; a fluid-structure coupling multi-physical field coupling modeling step, which integrates pipeline wall elastic deformation, fluid compressibility and viscous dissipation effect into a unified coupling analysis framework; and a pressure wave propagation solving step based on an improved characteristic line method, the system comprising a topology modeling module, a fluid-structure coupling modeling module, a pressure wave solving module, a path tracking module, a working condition switching module, a parameter calibration module, a data management module and a visualization display module, the application can accurately reflect the actual propagation behavior of pressure waves in a pipeline with a complex topology structure, significantly improve the simulation accuracy and maintain high prediction ability during working condition switching.

This invention relates to the field of adhesive technology and discloses a production process for lignin-based hyperbranched adhesives for high-salt conditions. The process includes: mixing natural lignin raw materials with an aqueous medium to construct a reactive, low-temperature bulk fluid; constructing a local reaction window using a viscous dissipative energy field generated at the outer edge of a shear stress generating component; injecting modified monomers and crosslinking agents into the window under a pressure gradient formed by the rotation of the shear component, inducing graft copolymerization, and then quenching under a cyclic temperature gradient to lock in a topological structure with a hydrophilic hyperbranched shell and a hydrophobic lignin core. This invention avoids the risk of localized disordered polymerization caused by global heat transfer hysteresis through spatial decoupling of the energy field and temperature field. The resulting topological structure utilizes the steric hindrance effect generated by the outer high-density hydration layer to block the electrostatic shielding of metal cations, thereby improving the homogeneous stability of the adhesive in a high-salt environment.

The application discloses a pump station equipment management and control early warning system based on Internet of Things, and relates to the technical field of pump station equipment management and control early warning of Internet of Things. The system comprises a multi-source sensing module, which is arranged at a key node of a pump station equipment and comprises a plurality of sensors and a collecting unit; an entropy production rate calculation module, which calculates viscous dissipation, heat conduction dissipation and total entropy production rate in real time through an embedded processor; a quantized health index generation module, which generates a health index and divides states; a fault tracing module, which positions a damage source based on gradient analysis of an entropy production cloud picture; and an early warning execution module, which triggers a three-level early warning protocol when a condition is met. The system further comprises a fluid-structure coupling solver and other units, adopts edge computing, cloud scheduling and national encryption algorithm encryption, and can realize early warning and accurate tracing of hidden faults of the pump station equipment, so as to guarantee safe and efficient operation of the equipment.

This invention discloses a symmetrical vortex focusing low-dissipation energy focusing device based on a Taiji double-vortex structure, relating to the field of civilian fluid energy focusing technology. The device includes a confined cavity body, a bidirectional symmetrical drive module, a Taiji double-vortex S-shaped flow channel unit, a steady-flow vortex core unit, a vortex array control module, and a directional energy release channel. Based on the principle of symmetrical vortex focusing low dissipation, this invention reduces fluid viscosity dissipation through the structural design of the Taiji double-vortex symmetrical flow channel. The steady-flow vortex core provides a fixed rotation center for the vortex to achieve vortex axis stabilization. The vortex control module with a Luoshu nine-square grid array layout realizes full-process program control of energy storage-amplification-release-depressurization. The device uses non-explosive civilian drive sources such as compressed air and civilian low-pressure lasers, without energetic materials or explosive components. The high-density energy after focusing is output as a highly collimated directional shock wave through a linear tapering nozzle. This invention effectively solves the technical problems of high energy dissipation, poor stability, weak controllability, and insufficient civilian adaptability of existing energy focusing devices. The energy utilization rate and vortex stability are both improved based on the structural design of the device. The device has the advantages of high energy focusing efficiency, strong controllability, compliance and safety, and wide applicability. It can be widely used in civilian fields such as medical rehabilitation shockwave therapy, low-altitude small drone security countermeasures, and non-destructive precision demolition in emergency rescue, and has good civilian promotion value.

The present application belongs to the technical field of fault prediction and health management of submarine cable fault detection equipment, and particularly relates to a deep-sea ROV carrier fault diagnosis method and system based on multi-source sensor fusion, comprising: geometric deconstruction is performed on the physical layout of the servo hydraulic system of the deep-sea ROV carrier, a hydraulic waveguide attenuation distribution tree containing a physical distance weight is reconstructed, a straight-through high-frequency data acquisition channel is established to extract a voltage signal corresponding to a high-frequency water hammer ripple, so as to obtain an initial ripple energy, combine a dynamic viscosity parameter, a high-frequency oscillation center frequency and a physical pipe inner diameter, calculate an expected arrival energy compensation waveform transit time delay by using a high-frequency thermal viscous dissipation mechanism, extract an actual arrival energy, subtract the expected arrival energy to obtain a physical leakage loss energy, and compare the physical leakage loss energy with an adaptive tolerance boundary to perform a node collapse operation or trigger an emergency stop instruction, so as to bypass the automatic oil replenishment mechanism interference, accurately locate the fault in the initial stage of micro-leakage and prevent high-pressure seawater from backflowing.

The invention relates to a method and a system for analyzing fluid-structure interaction energy dissipation of a multi-body floating structure. The system comprises a synchronizer which is connected with a data processing and analyzing device and is used for synchronizing a high-speed camera, a PIV laser transmitter, a wave maker controller and a wave height acquisition instrument; the analysis method comprises the following steps: under the condition of synchronization, acquiring a set average velocity field corresponding to each frame of PIV image in multiple frames of PIV images; wherein the multiple frames of PIV images are PIV images at different moments in a wave period; the set average velocity field corresponding to each frame of PIV image is obtained by averaging instantaneous velocity fields of a plurality of regular waves selected in B repeated tests under the same working condition at corresponding moments; each frame of PIV image comprises a viscous dissipation area in a surface boundary layer of the multi-body floating structure and an energy dissipation area used for representing an area of energy dissipation caused by flow separation, so that the test cost is effectively reduced, and the analysis efficiency is remarkably improved.

The present application relates to injection molding process control technical field, especially to modified ABS injection molding process parameter adaptive control system, through the physical field space-time acquisition module extracts melt transient electric signal and constructs multi-physical quantity initial matrix, generates space-time gradient tensor flow by using finite difference operation. Riemann orthogonal decoupling module establishes non-Euclidean space model based on nonlinear shear thinning constitutive parameter, and through the orthogonal decomposition of geodesic line, the pure viscous dissipation vector and the pure thermal work vector are stripped out. The phase change cooperative decision module generates shear compensation pulse and temperature adjustment parameter accordingly, which is converted into thrust waveform instruction and steady heat instruction by the instruction pulse issuing module. The injection propulsion servo unit executes mechanical thrust action with high-frequency oscillation, and the barrel matrix heating unit synchronously carries out heat compensation. The present application realizes the deep decoupling of physical parameters and improves the stability of modified ABS molding process.

This invention discloses a method for simulating the flow field of rocket exhaust jet impacting a vertical launch device, belonging to rocket launch technology. This invention establishes a flow model of the rocket's takeoff force and thermal environment based on nested mesh technology. The inviscid flux of the multi-component Navier-Stokes equations containing exhaust gas transport is discretized using an improved Roe scheme, and the inviscid flux at the grid cell boundaries is obtained. After setting boundary parameters for the flow model, a Realizable k-ε turbulence model is used to solve the viscous dissipation in the Navier-Stokes equations, and the viscous flux is discretized using a central difference method to complete the entire calculation. The advantages of this invention compared to existing technologies are reduced computation time; the use of nested meshes, the improved Roe scheme, and pressure ramp techniques allows for better simulation of actual conditions, effectively solving the problem of simulating the exhaust jet flow field during ignition at different attitude angles, altitudes, and velocities of ejected rockets.

This invention discloses a method and apparatus for enhancing mass transfer within microdroplets, belonging to the field of microfluidics technology. The method includes the following steps: Step 1: Substrate preparation: Prepare a hydrophobic substrate with a static contact angle θ ≥ a set threshold; utilize the low solid-liquid contact area, weak wall viscosity dissipation, and low vibration damping characteristics of the hydrophobic substrate to reduce droplet oscillation attenuation and retain vibration energy; Step 2: Droplet fixation: Add the target droplet to the surface of the hydrophobic substrate to form a fixed droplet; Step 3: Vibrational mass transfer: Apply vertical / horizontal periodic mechanical vibration to the hydrophobic substrate containing the fixed droplet, controlling the vibration frequency and amplitude. This invention reduces droplet vibration damping by controlling the wettability of the substrate surface, and combines this with mechanical vibration to generate strong convective circulation within the droplet, significantly improving the mixing and mass transfer efficiency by 1-2 orders of magnitude compared to pure diffusion.