37 results about "Diffusion flux" patented technology

The present invention relates to a fluent-based dust explosion simulation method. Although numerical simulation has become an increasingly popular research tool, there is a lack of good models for describing the interaction between phases and between particles. The method provided by the present invention is characterized in that: for the gas-conservation equation of the general form of gas in thetwo-dimensional region, the finite volume method in the discretization method is used to calculate the fluid dynamics software FIUENT; in the integration process, constitutions of the convective fluxof the solved function itself on the interface and of the first derivative diffusion flux of the solved function are assumed to form different discrete formats; and only a discrete equation derived by using the finite volume method can guarantee conservation as long as the control volumes located on both sides of the interface in the interpolation method on the interface are the same. The methodprovided by the present invention is simple in calculation, and pseudo-diffusion cannot be generated when the particle has a more complex change experience and the motion value calculation of the particle can be better tracked.

The invention relates to a magnetic component, and specifically relates to a multi-segment air gap type magnetic component. The multi-segment air gap type magnetic component comprises a first magneticcore and a second magnetic core, wherein the first magnetic core and the second magnetic core are symmetrically arranged, the left ends and the right ends of the first magnetic core and the second magnetic core are in butt joint with each other respectively, and central posts of the first magnetic core and the second magnetic core are opposite; a plurality of central post magnetic gaskets laminated vertically are assembled between the central post of the first magnetic core and the central post of the second magnetic core; and air gaps are formed between the central post of the first magneticcore and the central post magnetic gasket on the topmost layer, between the central post of the second magnetic core and the central post magnetic gasket on the bottommost layer and among the centralpost magnetic gaskets. Compared with a traditional magnetic component, the loss of leakage flux can be reduced and dispersed effectively, and the diffusion flux is reduced, so that the operating temperature of the magnetic component is reduced, and the operating efficiency of the magnetic component is promoted.

The invention provides a method for calculating molecular diffusion coefficients through non-equilibrium molecular dynamics simulation. According to the method, the molecular dynamics simulation is purely adopted to directly calculate the concentration gradients and diffusion fluxes of components in mixtures along the diffusion direction, so that the molecular diffusion coefficients of the components can be accurately calculated. Compared with a double-control volume grand canonical molecular dynamics (DCV-GCMD) simulation method, the method provided by the invention is capable of effectively improving the simulation efficiency and remarkably reducing the simulation program compiling difficulty.

The invention relates to a diffusion chamber and a diffusion method used in process of producing semiconductor. A diffusion source is changed into a plane, parallel to a semiconductor sample, from points through a diffusion control device, namely, distances from the diffusion source to all areas of the sample are equal, the concentration degree and diffusion depth can be controlled, and the diffusion flux can be controlled in the semiconductor production process; the diffusion concentration and depth uniformity can be greatly improved, the concentration of source materials are evenly distributed in the semiconductor sample, and further the overall uniformity and yield of the sample can be greatly enhanced. The diffusion control device and a diffusion route thereof are close to the diffusion source (the source materials), once the source materials are volatilized, the diffusion control device can firstly play a blocking role, so that the lower surface of the diffusion control device is fast filled with the source material uniformly, then the source materials are redistributed by the diffusion route so as to uniformly arrive at all areas of the sample.

The application provides an integrated magnetic element device and a converter, which relate to the technical field of magnetic elements, including: primary and secondary windings and a magnetic core; the primary and secondary windings are arranged around the magnetic core, and the primary and secondary windings are used for transformers and The inductance provides the winding; the coupling degree of the primary and secondary windings outside the window of the core is higher than the preset coupling degree; the coupling degree of the primary and secondary windings inside the window of the core is lower than the preset coupling degree, which relieves the magnetic core Outer diffusion MFL is a big technical problem through.

The invention discloses an integrated magnetic coupled inductor in the shape of Chinese character mu, wherein the inductor is composed of an iron core body in the shape of Chinese character mu and two-phase coils; the iron core body in the shape of Chinese character mu is composed of four ''U'' shaped iron cores; the magnetic poles of two ''U'' shaped iron cores are arranged oppositely and form a square shaped iron core; the two-phase coils are wound on the two magnetic poles of the square shaped iron core; the other two ''U'' shaped iron cores are arranged at two sides of the magnetic poles of the square shaped iron core and are buckled on the two-phase coils; and the two magnetic poles of the other two ''U'' shaped iron cores keep certain distances with the magnetic poles of the square shaped iron core, thus forming air gaps. The inductor has the advantages that the inductor is used for inductance coupling integration; the quantity of the air gaps is doubled; the lengths of the air gaps are reduced to a half; the air gaps are symmetrical; the diffusion fluxes of the air gaps are clearly reduced; the mutual inductive magnetic circuit of the two coils is the shortest without the air gap; the mutual inductance and the self-inductance are high; the energy and the material are saved; and the electromagnetic interferences are reduced.

The invention discloses a root system simulation collecting system for monitoring diffusion flux of PAHs in soil. The root system simulation collecting system comprises a passive type soil solution collecting bin and a PAHs root system simulation collecting system arranged in the collecting bin. The passive type soil solution collecting bin comprises a collecting bin body glass column pipe, a Teflon jacket arranged on the bottom of the glass column pipe in a sleeving mode and a ground jacket arranged on the top of the glass column pipe in a sleeving mode, and a multihole water inlet with holes in the side portion is formed in the lower middle portion of the glass column pipe. The PAHs root system simulation collecting system comprises an SPE extraction column pipe arranged in the glass column pipe, the upper portion of the SPE pipe is packed with a glass hollow support pipe, and the upper portion of the support pipe is sealed through a rubber stopper. The multihole water inlet is formed in an annular inward-concave mode. A glass fiber filter membrane, a polytetrafluoroethylene millipore filtration interlayer and a stainless steel mesh support layer are sequentially arranged in the inward-concave position from interior to exterior. The root system simulation collecting system can be applicable to collecting and diffusion flux testing of PAHs in percolate under different natural environments, and the system is reasonable in design, simple in manufacturing process, low in cost, convenient to operate, efficient and durable.

The invention provides a method for distinguishing gaseous water dispersing mode in bituminous mortar, and belongs to the field of traffic pavement materials. The method comprises the following steps:manufacturing a thin-sheet type bituminous mortar test part of which the diameter-height ratio is beyond 10: 1; performing gaseous water absorbing test under constant temperature T and different relative humidity phi conditions; calculating equilibrium absorption capacity of the test part in each humidity; then performing gaseous water dispersing test under a constant-temperature and constant-humidity condition, wherein the constant temperature is identified as T; testing the overall mass of the test part device in different time until the stable stage that mass varies at constant speed as time goes one is achieved; then calculating the data obtained from the absorbing test and the dispersing test; and calculating the proportion of the diffusion flux of different dispersing modes in the total diffusion flux. With the adoption of the method, the problem that the gaseous water dispersing mode in the bituminous mortar cannot be distinguished by the prior art can be solved; and the methodis applicable to bituminous mortar damage mechanism study.

The invention discloses a performance detection method of a porous media burner, which includes: establishing a mathematical model of the premixed combustion process in the porous media burner; wherein, the diffusion approximation method and the double flux method are used to establish the premixed combustion process The mathematical model of the radiation heat transfer process; obtaining the structural parameters of the porous media burner to be detected; simulating the premixed combustion process in the porous media burner to be detected; comparing the simulation results with the preset performance indicators, The combustion performance of the porous media burner to be tested is tested. In addition, a performance detection device of a porous media burner is also disclosed. The invention obtains various combustion performance indexes of the porous medium burner in the premixed combustion process, and then compares them with preset performance indexes to achieve the purpose of detection and verification. Combining the diffusion approximation method and the double-flux method to simulate the radiation heat transfer process makes the detection results more accurate and reliable.

The invention discloses an in-situ sampling device, a detection device and a detection method for the maximum diffusion flux of sediment-water interface pollutants. The sampling device includes an annular upper shell, a fixed film and a lower shell. The lower shell The top is provided with a groove for accommodating a fixed film, the fixed film is arranged in the groove of the lower shell, and the upper edge of the annular upper shell is provided with a plurality of fins at intervals, and the annular upper shell It is sleeved on the upper end of the lower casing and the fixed film is fixed, and the average density of the sampling device is greater than that of water. The invention can measure the maximum diffusion flux of the sediment, has the advantages of convenient operation, relatively small experimental intensity; strong applicability, wide range of target objects that can be measured; small volume, and can be deployed in a large range of lakes to estimate the release of the entire lake Flux and other advantages.

In the vacuum carburizing treatment method according to this embodiment, the flow rate of carburizing gas calculated from the diffusion flux of carbon in the surface layer of the steel material obtained from the diffusion simulation using the diffusion equation is defined as the theoretical carburizing gas flow rate (FT) , the moment when the actual carburizing gas flow rate is equal to the theoretical carburizing gas flow rate after the carburizing process starts is defined as the intersection time te, and the time from the beginning to the end of the carburizing process is defined as the carburizing time ta, and the carburizing process is defined as The time of 1 / 5 of the time is defined as the reference time ta / 5. At this time, in the early carburizing process (S1) from the start of the carburizing process to the intersection time te, the actual carburizing gas flow rate (FR) It is: the theoretical carburizing gas flow rate (FT(te)) above the reference time ta / 5 from the start of the carburizing process, and the theoretical carburizing gas flow rate (FT(20s) at 20 seconds from the start of the carburizing process )) or less; in the late carburizing process (S2) from the intersection time te to the carburizing time ta, the actual carburizing gas flow rate (FR) is 1.00 to 1.20 times the theoretical carburizing gas flow rate (FT) within range.

The invention discloses a short-gap gas discharge numerical simulation method based on the time-domain spectrum element method. The steps of the method are as follows: establish a structural model of short-gap gas, and discretize it to obtain the structural information of the model; use the GLL basis function based on the spectral element method to discretize, and perform the Galerkin test to obtain the expression of the high-order scheme; for the Stiffness matrix, by eliminating the negative elements outside the diagonal, the expression of the low-order scheme is obtained; the expressions of the high-order and low-order schemes are subtracted to obtain the original back-diffusion flux and pre-limited; the correction factor is calculated, Finally, the limited back-diffusion flux is obtained, and the limited back-diffusion flux is added to the expression of the low-order scheme, time is discretized through the multi-step backward difference scheme, and Newton iteration is used to solve at each time step, Get the electron density and ion density of the gas, calculate the electric field and update the transport parameters. The invention can achieve unconditional stability in terms of time, high calculation precision and good simulation effect.

The invention relates to a leadless solder joint interface metallic compound growth thickness prediction method and a system thereof. The method comprises the following steps: determining a leadless solder joint interface model and a target metal atom, obtaining the electromigration flux, dissolving flux and net-heat diffusion flux, calculating the thickness change rate of a cathode interface metallic compound layer and an anode interface metallic compound layer, according to the thickness change rate and initial thickness, obtaining the thickness of the cathode interface metallic compound layer and the anode interface metallic compound layer at any time. The above method can accurately predict the growth thickness of the interface metallic compound layer.