7 results about "Particle loss" patented technology

This application discloses a two-stage virtual impactor for sorting submicron particles, belonging to the field of aerosol separation. The virtual impactor includes a housing and a first-stage and a second-stage virtual impactor disposed within the housing. Both the first-stage and second-stage virtual impactors are arranged parallel to each other along the length of the housing. A deflection channel is also provided within the housing. One outlet of the first-stage virtual impactor is connected to the inlet of the second-stage virtual impactor through the deflection channel. This virtual impactor, through staged processing, optimizes design parameters for each stage within a specific particle size range, resulting in a more uniform particle group and reducing the probability of non-target impacts on the wall due to mixing. This design systematically reduces particle losses caused by inertial impaction, turbulent entrainment, and other mechanisms, enabling it to better adapt to low-concentration, high-precision particle separation, significantly improving separation efficiency and data reliability.

The utility model relates to the technical field, in particular to a particle-loss-preventing dewatering well structure adjacent to an existing station, which comprises an existing tunnel and a newly-built foundation pit above the existing tunnel, and is characterized in that a dewatering well body is excavated around the existing tunnel and the newly-built foundation pit, a permeable pipe is arranged in the dewatering well body, and the permeable pipe is communicated with the existing tunnel and the newly-built foundation pit. Gravel, fine sand and sponge are filled between the dewatering well body and the permeable pipe, and a dewatering well limiting assembly is arranged at the top of the dewatering well body. In the process of dewatering underground water on the dewatering well body through the permeable pipe, a multi-stage inverted filter structure formed by the gravel, the fine sand and the sponge is adopted, so that sand particles are prevented from being lost along with water flow, the piping phenomenon is effectively prevented, and the safety and the stability of an existing tunnel are protected.

This invention provides a pipeline flow field tracer particle injection system and method for use in gas transmission pipelines. The system includes: a particle injection unit, a laser emission unit, and an image acquisition unit. The pipeline is divided into an injection zone and an emission / acquisition zone according to the particle's direction of travel. The particle injection unit is located in the injection zone and is used to inject tracer particles into the pipeline. The laser emission unit and image acquisition unit are located in the emission / acquisition zone and are respectively used to emit laser light into the detection zone within the pipeline and to acquire particle images of the detection zone. A control unit, connected to the particle injection unit and the image acquisition unit, is used to obtain the effective sampling number of tracer particles based on the particle images and to adjust the particle injection volume within the pipeline according to the effective sampling number. The pipeline flow field tracer particle injection system of this invention has a simple structure, can quickly and accurately adjust the particle injection volume, reduce particle loss, improve experimental efficiency, and enhance the accuracy and safety of the tracer particle injection process.

The invention discloses a novel fine grain loss collecting and measuring device and a testing method, and belongs to the field of civil engineering and hydraulic engineering, the device comprises two sets of vertical rising precipitation devices and a flocculation water storage device, the device is designed according to the particle critical suspension flow velocity principle, coarse and fine grain grading separation is achieved through an obliquely-arranged double-layer detachable filter screen (0.25 mm + 0.075 mm), and the fine grain loss collecting and measuring device is designed according to the particle critical suspension flow velocity principle. The content of fine particles is monitored in real time in cooperation with a turbidity meter; test water is preliminarily precipitated by the vertical rising precipitation device and then enters the flocculation water storage device to fully react with 0.2%-0.5% polyaluminum chloride flocculant, deep purification is realized, and the purified water is supplied to the test again through the water supply pipe to form closed-loop circulation. According to the invention, a dual-system alternate working mode is adopted, non-stop continuous determination of the test is realized, and the test efficiency is improved by more than 30%; the fine grain loss determination adopts turbidity meter real-time monitoring and drying and weighing dual verification, and the error is less than or equal to 5%; the utilization rate of test water reaches 90% or above, and the problems that in the prior art, measurement deviation is large, water is wasted, and shutdown detection is needed are solved.

The application provides a cyclotron electrostatic deflection plate beam loss heat source reconstruction method, and relates to the technical field of particle accelerator heat analysis and multi-physical field coupling calculation, and the method comprises the following steps: step 1, configuring beam dynamics simulation parameters, performing multi-particle tracking under a three-dimensional field diagram containing a central area electromagnetic field, a harmonic coil magnetic field and an electrostatic deflection electric field, and generating a particle loss list; step 2, converting the particle loss list into a beam source file of a Monte Carlo radiation transport program, configuring Monte Carlo parameters, including deflection plate materials, boundaries, particle types and energy spectra, performing particle transport simulation, and obtaining a three-dimensional energy deposition matrix on the electrostatic deflection plate element. The application realizes high-resolution heat source reconstruction, can reduce the calculation error of the peak temperature rise of the deflection plate, and can feed back the temperature field solving result to optimize the particle source, thereby providing a reliable basis for the thermal structure design and cooling optimization of the electrostatic deflection plate.

The invention provides a steady-state quantum turbulence generation method and a steady-state quantum turbulence generation system capable of guaranteeing particle number conservation. The method comprises the following steps: constructing an evolution model of the quantum fluid system, wherein the evolution model is obtained by introducing an external driving item and a particle number conservation dissipation item based on a Gross-Pitaevskii equation; the external driving item is an additional external potential of spatio-temporal variation and is used for injecting energy into the system; the particle number conservation dissipation item depends on the time change rate of the particle number density and is used for dissipating the energy of the system; the external driving item and the particle number conservation dissipation item are configured to keep the total particle number conservation of the system; and performing time evolution on the quantum fluid system based on the evolution model until the system reaches a steady-state quantum turbulence state of total kinetic energy dynamic balance. According to the method, the loss of chemical potential compensation particles does not need to be adjusted, quantum turbulence structures of different scales can be stably generated and regulated, and the physical self-consistency and long-term stability of the quantum fluid evolution process are guaranteed.

The invention discloses a gravel soil side slope hydraulic erosion test device and method. The device comprises a model water tank, a side slope model arranged in the model water tank, a water supply assembly connected with the model water tank and a monitoring assembly arranged outside the model water tank. The device is reasonable in structural design and stable and reliable in operation, and through multi-scale tests and numerical simulation, a positive feedback mechanism that fine particle loss drives pore structure recombination, induces skeleton instability and accelerates fine particle loss due to skeleton damage in the seepage erosion process of the slope model is disclosed. The progressive degradation rule and the collapse instability mechanism of the gravelly soil side slope under the action of seepage erosion are further clarified, a new theoretical framework is provided for understanding the collapse instability of the side slope, and the cognitive direction of monitoring and early warning research on the instability of the gravelly soil side slope is expanded.