Direct Modeling Method Research Articles

Capturing sclera anisotropy using direct collagen fiber models. Linking microstructure to macroscopic mechanical properties.

Because of the crucial role of collagen fibers on soft tissue mechanics, there is great interest in techniques to incorporate them in computational models. Recently we introduced a direct fiber modeling approach for sclera based on representing the long-interwoven fibers. Our method differs from the conventional continuum approach to modeling sclera that homogenizes the fibers and describes them as statistical distributions for each element. At large scale our method captured gross collagen fiber bundle architecture from histology and experimental intraocular pressure-induced deformations. At small scale, a direct fiber model of a sclera sample reproduced equi-biaxial experimental behavior from the literature. In this study our goal was a much more challenging task for the direct fiber modeling: to capture specimen-specific 3D fiber architecture and anisotropic mechanics of four sclera samples tested under equibiaxial and four non-equibiaxial loadings. Samples of sclera from three eyes were isolated and tested in five biaxial loadings following an approach previously reported. Using microstructural architecture from polarized light microscopy we then created specimen-specific direct fiber models. Model fiber orientations agreed well with the histological information (adjusted R2's>0.89). Through an inverse-fitting process we determined model characteristics, including specimen-specific fiber mechanical properties to match equibiaxial loading. Interestingly, the equibiaxial properties also reproduced all the non-equibiaxial behaviors. These results indicate that the direct fiber modeling method naturally accounted for tissue anisotropy within its fiber structure. Direct fiber modeling is therefore a promising approach to understand how macroscopic behavior arises from microstructure.

Research on rolling bearing fault diagnosis method based on simulation and experiment fusion drive.

Aiming at the problem that the rolling bearing fault data are difficult to obtain and that the traditional fault diagnosis method does not consider the signal uncertainty characteristics and the low accuracy of models in the process of rolling bearing fault, a fault diagnosis method based on simulation and experiment fusion drive is proposed. First, the dynamics simulation model of rolling bearings under different fault conditions is established to obtain the bearing fault simulation signals. Second, a sequence generative adversarial network is used to fuse the simulation and experimental data. Bearing vibration signals are often very uncertain, so considering the probability characteristics of fault signals, the probability box model under different fault states is constructed by the direct probability box modeling method, and its characteristic vectors are extracted. Finally, an extreme gradient boosting Tree model for fault diagnosis classification is constructed to compare and evaluate the classification and diagnosis effects of bearing states before and after data fusion. The results show that the proposed method has a good diagnostic effect and is suitable for solving the fault diagnosis problem under the condition of insufficient data.

Efficient modelling of surface roughness effects in additively manufactured materials

3D printing defects are often used to explain the mismatch between numerical predictions and experimental results of additively manufactured acoustic materials. Although they are often perceived as desirable, as in most cases, they improve the absorptive behaviour of the system, occurring gains are unplanned and uncontrollable. Among different 3D printing inaccuracies, surface roughness provides additional acoustic losses, mostly due to the enlargement of the boundary layer thickness. On the other hand, roughness is responsible for the shift of the operating frequency compared to the numerical predictions. The goal of this research is to provide efficient modelling methods to capture the effects of surface roughness arising from the additive manufacturing process. First, a direct modelling method will be discussed, which can be computationally expensive as it relies on an accurate geometrical representation of surface roughness. Second, an alternative indirect modelling approach will be presented, which mimics the presence of roughness by adjusting specific air parameters in the locations of interest of the smooth geometry to reduce the computational cost. The two strategies will be compared with each other and to the results of an experiment where additional roughness is added to target locations within the design.

Исследование электровихревого течения между плоскостями с помощью различных вычислительных подходов

Electrovortex flows arise when an electric current of varying density passes through a well-conducting fluid (e.g., acid or metal melt). In such a case, the electric current generates a magnetic field, which leads to the Lorentz force causing swirling currents of the medium. There are different methods of theoretical study of such currents. As a rule, to avoid the necessity to find the pressure dependence on coordinates, the variables "vector potential of velocity - swirl" ("scalar current function – swirl" in the case of axisymmetric flows) are used. In such a case, it is quite effective to use automodel variables, which allow to reduce the dimensionality of the problem. In this case, the solution for the introduced function can be sought in the form of an expansion by the electro-vortex flow parameter proportional to the square of the magnetic Reynolds number. Also, this solution can be obtained numerically, for example, using finite-difference methods. Nowadays, more and more often the solutions are investigated by means of direct numerical modeling methods, when no automodel approximations are made, which reduce the accuracy of the solution. Nevertheless, in such a case the number of computations can be quite large and requires the use of supercomputer resources. A separate difficulty is presented by the boundary conditions: for example, for the velocity vector potential we obtain a fourth-order equation, which imposes significant restrictions on the time steps in the evolution equation. The problem can be avoided by using approximate boundary conditions, but this again reduces the accuracy of the solution. In this paper, using the example of electro-vortex flow between planes, the solutions that can be obtained using the various computational approaches mentioned above are examined. The results obtained are compared, and they are also compared with analytical approximations.

Numerical Modeling and Application of Horizontal-Axis Wind Turbine Arrays in Large Wind Farms

The global supply of energy is still tight, even with the rise of renewable energy utilization and abundant wind energy. More and more large wind farms have been installed globally. As of 2020, China’s total installed capacity accounted for 38.8%, far ahead of other countries. The layout of horizontal-axis wind turbine (HAWT) arrays in large wind farms poses three main issues: (1) How to select a site. (2) How to arrange the HAWT arrays to achieve greater power extraction at a specific wind farm. (3) How to reduce the noise generated by HAWTs. The numerical simulation of a HAWT wake field generally includes the analytical method (AM), vortex-lattice or vortex particle method (VM), panel method (PM), blade element momentum method (BEM), generalized actuator method (GAM), and direct modeling method (DM). Considering the computational cost, this paper combines DMs and mainly adopts the BEM-CFD coupling method, including uniform and non-uniform loading of axial force. Forty specially designed numerical experiments were carried out, which show that: (1) the BEM-CFD method greatly improves the calculation speed within the accuracy range of a thrust coefficient less than 2.5%, making it very suitable for the calculation of large wind farm HAWT arrays; (2) for regular HAWT arrays, it is reasonable to choose a 6D spacing in the wind direction and a 4D spacing in the crosswind direction for simplicity in practice.

Numerical Study on the Effect of Partial Delamination of Thermal Barrier Coating on the Cooling Effect of Turbine Blade

A localized delamination modeling method based on a thin-wall thermal resistance model is developed in this study. Numerical investigations are then conducted with this model to analyze the influence of factors such as the position, area, shape, and depth of localized delamination on blade cooling efficiency. Firstly, the simulation results of two coating modeling methods (the thin-wall thermal resistance model and the direct modeling method) are examined. Then, the overall insulation efficiency of the blade surface with a complete thermal barrier coating is analyzed based on the thin-wall thermal resistance model. Subsequently, the impact of different delamination factors on blade cooling effectiveness is explored. The research results indicate that compared to the direct modeling method, the thin-wall thermal resistance model has a simulation deviation of less than 7% and can effectively improve modeling and simulation efficiency while ensuring computational accuracy. The highest insulation efficiency of the thermal barrier coating is observed in the middle section of the blade’s back surface near the cold air inlet, reaching 8.3%. Under a constant delamination area, the shape of the localized delamination has a minor effect on blade cooling effectiveness. When more delamination occurs in areas with higher insulation efficiency, the impact on blade cooling effectiveness becomes more significant.

Soil–Structure Interaction Effects on a Regional Scale through Ground-Motion Simulations and Reduced Order Models: A Case Study from the 2008 Mw 5.4 Chino Hills Mainshock

ABSTRACT We demonstrate the effects of soil–structure interaction (SSI) for three idealized building typologies on a regional scale, using a simulated earthquake scenario of the 2008 Mw 5.4 Chino Hills mainshock in southern California as an example. All the three buildings lie on shallow foundations, and they are subject to three-component simulated ground motions. To carry out this task, we develop a reduced order model (ROM) for each building typology that accounts for the effects of SSI on the building system in the time domain. We specifically use ensemble Kalman inversion (EnKI) to extract the soil impedance values from fully coupled soil–foundation–structure interaction simulations; and we interpolate the EnKI results to derive analytical functions that span the range of applicability of the soil impedance model. We then verify our ROMs by comparing results to fully coupled soil–foundation–structure interaction simulations, also known as direct modeling methods. We finally populate the simulation grid across southern California with the verified building ROMs, and interpret the responses in the form of maps that represent urban-scale effects of SSI on the seismic demand parameters such as maximum displacement, acceleration, and interstory drift. We also identify areas where the effects of SSI, given the resonant characteristics of a specific building, the foundation typology, and the local site conditions, lead to higher seismic demand relative to the fixed-base response.

TO THE CALCULATION OF RING PLATES ON A VARIABLE ELASTIC BASE

The article examines the bending of ring plates on a variable elastic base. There are different models of elastic base. The simplest is the Winkler model, or the spring model. For beams on a constant elastic base, this model allows obtaining an exact solution, but not for slabs. The case is even more complicated when the elastic basis is variable. There is no single approach to building a universal analytical solution. Therefore, numerical calculation methods are used in engineering practice. The analytical method of direct integration and computer modeling in PC LIRA-CAD with subsequent calculations by the method of finite elements are used. Two examples are considered: a steel plate, which is rigidly clamped along the inner contour, and its outer contour is hinged, and a concrete slab, which is rigidly clamped along the outer contour, and its inner contour is hinged. The results of the numerical implementation show that the values of deflections when calculated by the author's method and the method of finite elements in PC LIRA-CAD practically coincide, and the difference in the values of bending moments reaches 10%. Moreover, the difference in deflections is manifested only in the fourth (and sometimes in the fifth) sign after the comma. It is noted that the method of direct integration demonstrated very high accuracy when solving numerous test problems that have an exact solution. The authors explain the discrepancy in the values of the bending moments obtained here by the semi-automatic breakdown of the finite-element mesh in PC LIRA-CAD. This statement is based on the fact that when the mesh is thickened in the circumferential direction, the results obtained by the two methods for determining the radial and circumferential bending moments are substantially converged.

A novel boundary tracing method without enrichment for modeling cracks and their propagation

A novel direct numerical modeling method for preexisting cracks and their propagation is developed based on the integral-generalized finite difference (IGFD) method which has an excellent performance in accuracy, flexibility, and convenience in dealing with boundary conditions. “Direct modeling” means discontinuities and their propagation are directly treated as boundaries of subdomains. The standard IGFD method for continuity problems is adopted in regions far from discontinuities, while modifications are required around the discontinuities. Some special treatments such as paired nodes and birth–death algorithms are employed to characterize the existing cracks and track the crack growth path. These techniques together constitute the extended IGFD (xIGFD) method realizing the application of IGFD method in discontinuity problems. Three specific technologies, xIGFD-A, xIGFD-B, and xIGFD-C are proposed to treat the growing nodes along the discontinuities. The xIGFD-A needs to number the newly generated nodes and add degrees of freedom for propagating cracks, which would change the dimensions of the global matrices, while the xIGFD-B and the xIGFD-C do not. The successful applications of this proposed xIGFD method as well as the comparisons with existing numerical methods in a series of examples involving quasi-static propagation of a single crack and cross cracks have fully proved its effectiveness and superiority. The proposed method neither needs enriched basis functions based on prior knowledge nor requires re-meshing operations, which shows the unity and conciseness of the discretization scheme for continuity and discontinuity problems. Therefore, it has application potential in more complex practical problems like hydraulic fracturing and fatigue cracks.

Direct modeling for computational fluid dynamics and the construction of high-order compact scheme for compressible flow simulations

Computational fluid dynamics is a direct modeling of physical laws in a discretized space. The basic physical laws include the mass, momentum and energy conservations, numerical scale-consistent transport process, and similar domain of dependence and influence in the physical and the numerical wave propagations. Therefore, a physically soundable numerical scheme should be a compact one which involves the closest neighboring cells within the domain of dependence for the solution update under a CFL number (∼1). In order to keep the compactness of the scheme and be high-order, subcell flow distributions or the equivalent degrees of freedom beyond the cell averaged flow variables are needed, such as the gradients of the flow variables inside each control volume. Under the above consideration, the direct use of Riemann solver as the evolution model doesn't provide such a mechanism. High-order dynamic evolution process should be used to update the time accurate cell-averaged flow variables and their gradients. The direct modeling of flow evolution under generalized initial condition will be developed. In order to provide reliable cell averaged flow variables and their gradients for the compact data reconstruction, the evolution process is constructed to provide possible discontinuous time-dependent flow variables across a cell interface. At the same time, the time accurate flux function at a cell interface can become a discontinuous function of time in its evolution process. Same as the spatial limiter in the conventional computational fluid dynamics methods, such as the total variation diminishing and weighted essentially non-oscillatory methods, the temporal limiter for the time accurate flux function is designed as well. The direct modeling method in this paper will update flow variables differently on both sides of a cell interface and nonlinearly limit the high-order time derivatives of the flux function in case of shock wave passing through a cell interface within a time step. The direct modeling method unifies the concepts of nonlinear limiters in spatial data reconstruction and temporal flux transport. The equivalent treatment of space and time makes the compact gas-kinetic scheme be super robust and accurate for the compressible flow simulation. At the same time, the 4th to 8th-order compact schemes can use a large CFL number (∼0.8) in flow computation, even for the hypersonic flow simulation.

Application of the method of direct mathematical modeling to diamond-shaped contact lines

The article describes the application of the numerical method to the investigation of the dynamic interaction of contact lines with current collectors of electric rolling stock (ERS). The law of joint movement of the runner and the contact wire shall be established. If agap is recorded at anystage, the pressure value is set to zero. From this point on, the flux and contact wire are modeled independently. The contact wire shall be touched by the current collector by the clearance δ. As arule, the introduction into contact is accompaniedbytheintroduction of acurrent collector into the contact wire, which is characterized by negative clearance δ<0. To compensate for the introduction atthepointof contact, there must be an additional «push» force defined by the condition of zero clearance at the end of the stage.

Direct Inverse Hysteresis Compensation of Piezoelectric Actuators Using Adaptive Kalman Filter

The hysteresis of the piezoelectric actuator exhibits obvious rate dependence, especially in fast scanning or tracking. This article proposes an adaptive hysteresis compensation method that integrates the direct inverse modeling (DIM) method and an adaptive Kalman filter (AKF). DIM is adopted to directly obtain the inverse hysteresis model and use it as the hysteresis compensator. AKF is utilized to dynamically update the weights of the inverse hysteresis model so as to eliminate the manual tuning of control parameters. Further, a forgetting factor is adopted in AKF to reduce the influence of the old data. Experimental results on tracking of step, sinusoidal, and triangular trajectories demonstrate the effectiveness of DIM + AKF in hysteresis compensation. The transient and steady state performances of the closed-loop system are significantly improved. A closed-loop bandwidth higher than 200 Hz is achieved. The robustness of DIM + AKF against the rate dependence is further verified using a 0–200 Hz swept sinusoidal trajectory. As the onsite tuning is successfully eliminated, DIM + AKF is easy to follow for inexperienced users.

Основные итоги деятельности Федерального центра медицины катастроф ФГБУ «Национальный медико-хирургический центр им. Н.И.Пирогова» и Службы медицины катастроф Министерства здравоохранения Российской Федерации в 2021 г.

The preparedness of the Russian health care to react to emergency situations, issues of organization and provision of medical care and medical evacuation in emergencies are inextricably linked to the activities of the Disaster Medicine Service of the Russian Ministry of Health, the main component of the All-Russian Disaster Medicine Service. Since March 1, 2021 day-to-day administration of the All-Russian Disaster Medicine Service and of the Disaster Medicine Service of the Russian Ministry of Health is performed by the Federal Center for Disaster Medicine of National Medical and Surgical Center named after N.I. Pirogov. The aim of the study is to define the priorities for the year 2022 for the Federal Disaster Medicine Center, for Disaster Medicine Service of the Russian Ministry of Health and for the All-Russian Disaster Medicine Service as well as for the whole system of population medical support in emergencies. The priorities will be defined based on the analysis of the 2021 year activities for the Federal Center for Disaster Medicine, for territorial centers of disaster medicine, for regional centers of emergency and disaster medicine and for regional centers of disaster and emergency medicine. Materials and research methods. Regulatory and methodological documents governing the organization and functioning of the All-Russian Disaster Medicine Service and of the Disaster Medicine Service of the Ministry of Health of Russia, documents setting the procedure for medical care and medical evacuation of victims in emergencies; reports of territorial centers of disaster medicine, of regional centers of emergency and disaster medicine and of regional centers of disaster and of federal disaster medicine centres on the medical and sanitary emergency response activities in 2021 as well as other documents; scientific papers and publications on current issues of medical care in emergencies, on development of the Disaster Medicine Service information environment and on digitalization of healthcare. Research methods: analytical statistical, method of direct observation, logical and informational modeling. Research results and their analysis. The main results of activities of Federal Disaster Medicine Center and of Disaster Medicine Service of the Russian Ministry of Health in 2021 were considered, including information interaction with the operational services in conference mode, monitoring of the medical and sanitary situation, emergency data, measures to combat the COVID-19 pandemic, etc. The structure of Disaster Medicine Service at the regional level was analyzed. The main directions of Federal Disaster Medicine Center and Disaster Medicine Service of the Russian Ministry of Health activities for 2022 are presented.

Determination of the minimum allowable parameters for the single-axis gyrostabilizer terminal control by direct simulation

The problem of determining the minimum control time at the terminal control of the platform motion of a uniaxial gyrostabilizer (UGS) is considered — a task for quick-action — in the mode of non-precision «coarse» reduction. The analyti cal way solution of this problem under constraints and uncertain perturbing influences causes difficulties. In this regard, it is proposed to use the method of direct modeling. With the help of the USG mathematical model families of its terminal output parameters and control actions for different control termination times ar e obtained. The end criterion of the terminal control process is the transition to the relay control mode. Keywords single-axis gyrostabilizer, terminal control, a task for quick-action, direct simulation method

PRESSURE MEASUREMENT OF INDUCED EXTERNAL ATMOSPHERE ON THE RUSSIAN SEGMENT OF THE INTERNATIONAL SPACE STATION IN EXPERIMENT «CONTROL»

The goals and objectives of space experiment Control to study parameters of the induced external atmosphere of the Russian Segment of the International Space Station are presented. The processing and analysis procedure for telemetry data obtained using scientific equipment Indicator - ISS is described. Numerical calculations were performed by direct statistical modeling of the flow around the pressure sensor by incoming flotation the Earth's outer atmosphere in the background measurement conditions, as well as in disturbed conditions with two vernier engines of the Zvezda module being operated. A correction function of the pressure sensor is obtained depending on the orientation, temperature factor and selected model of interaction of incident flow molecules with the internal and external device surfaces. The results of numerical modeling of the jet discharges of the the Zvezda vernier engine were compared with the data obtained in full-scale pressure measurements in experiment Control. Key words: pressure sensor, orbital station, induced external atmosphere, direct statistical modeling method.

Experimental and numerical simulations on compound stress intensity factor of semi-elliptical cracks on the exchanger outer walls with inclined angles

Based on the theory of elastic fracture and using direct modeling method, a numerical model was developed for solving the composite stress intensity factor of semi-elliptical cracks on exchanger outer walls with inclined angles. The model exchanger had an outer diameter of φ50 mm, inner diameter of φ44 mm and length of 300 mm. The values of crack plane inclination β (0°, 10°, 20°, 30°, 40° and 45°), crack depth a (0.5 mm, 0.75 mm, 1 mm and 1.25 mm), and crack shape ratio a/b (0.4, 0.5, 0.55, 0.6, 0.7, 0.8, 0.9 and 1.0) were obtained and 3D surface crack model was established. The results were significance for the evaluation of the remaining life of exchanger components.

Joint tomographic inversion of crustal structure beneath the eastern Tibetan Plateau with ambient noise and gravity data

SUMMARY We have developed a joint tomographic inversion method with seismic surface wave dispersion and gravity data for obtaining more reliable crustal 3-D shear wave structures. We take the eikonal-based direct surface wave tomographic method and adaptive gravity modelling method in spherical coordinates in the inverse problem. Based on the empirical relations between seismic velocity and density parameters, our method combines surface wave dispersion curves (i.e. surface wave traveltimes at different periods) and Bouguer gravity anomaly data together to invert for 3-D shear wave velocity structures. In our method, off-great-circle propagation of the surface wave and the earth's curvature is considered in the forward modelling. Synthetic tests suggest that the joint tomographic method could improve the reliability and obtain more convincing results than individual seismic surface wave tomography. The gravity data can provide more constraints into the model resolution and help restore the crustal anomalies better. The inversion results in the eastern Tibetan Plateau and Sichuan basin indicate complex distributions of low-velocity zone in the mid-crust of the eastern Tibetan Plateau and a craton-like basement of the Sichuan basin, which supports the crust channel flow model. Although both the 3-D shear wave velocity model from joint inversion and the individual seismic surface wave inversion can fit the surface wave data almost equally well, the joint inversion model can better match the gravity data We also found that the 3-D model from joint inversion in this study shows similar structural characteristics with the surface wave tomographic model, which indicates the icing on the cake effects of gravity data.

A robust direct modeling method for quadric B-rep models based on geometry–topology inconsistency tracking

Boundary representation (B-rep) model editing plays an essential role in computer-aided design, and has motivated the very recent direct modeling paradigm, which features intuitive push–pull manipulation of the model geometry. In mechanical design, a substantial part of B-rep models being used are quadric models (composed of linear and quadric surfaces). However, push-pulling such models is not trivial due to the possible smooth face–face connections in the models. The major issue is that, during push–pull moves, it is often desirable to preserve these connections for functional, manufacturing, or aesthetic reasons, but this could cause complex inconsistencies between the geometry and topology in the model and lead to robustness issues in updating the model. The challenge lies in effectiveness towards detecting the instants when geometry–topology inconsistencies occur during push–pull moves. This paper proposes a novel reverse detection method to solve the challenge and then, based on it, presents a robust method for push–pull direct modeling while preserving smooth connections. Case studies and comparisons have been conducted to demonstrate the effectiveness of the method.

On A Methods Of Using Weighted Simulation Improving Reliability To Redundant Fiber Optic Communication Systems

The article describes the methodology of weighted modelling to increase the reliability of redundant fibre-optic communication systems. In a specific example, a network graph of a many-node fibre-optic communication system is considered. Applying general ideas to determine the reliability characteristics of systems consisting of a large number of different types of elements with different functional relationships between them is quite a difficult task. The materials presented in this article are intended to solve this problem. Along with their relative simplicity, they are highly accurate. The numerical examples in this chapter show that the use of these methods for highly reliable systems can reduce the variance of the estimate by several orders of magnitude compared to the direct modelling method, and thus reduce the time required for calculations on electronic computers by several orders of magnitude. The purpose of the study is to increase the reliability of fibre-optic communication systems. The research methodology is based on models with a limited number of monotonous failure chains, which is available for visual enumeration of the reliability of highly reliable systems. As a result, it is proposed to obtain an approximate formula for assessing the reliability of a highly reliable system, both by modelling and analytically, and calculations using it can be performed using the quadrature method or moment methods. This allows you to build a model according to the block principle, including full-scale blocks or records of the results of their tests, simplifies the interpretation of the results, and creates convenience in software implementation.

A velocity-space adaptive unified gas kinetic scheme for continuum and rarefied flows

Compressible flow has intrinsically multiple scale nature due to the large variations of gas density and characteristic scale of flow structure, especially in hypersonic and reentry problems. It is challenging to construct an accurate and efficient numerical algorithm to capture non-equilibrium flow physics across different regimes. In this paper, a unified gas kinetic scheme with adaptive velocity space (AUGKS) for multiscale flow transport will be developed. In near-equilibrium flow region, particle distribution function is close to the Chapman-Enskog expansion and can be formulated analytically, where only macroscopic conservative flow variables are updated. With the emergence of non-equilibrium effect, the AUGKS automatically switches to the original unified gas kinetic scheme (UGKS) with a discrete velocity space to follow the evolution of particle distribution function. A criterion is proposed to quantify the non-equilibrium and is used for the switch between continuous and discrete particle velocity space. Following the scale-dependent local evolving solution, the AUGKS presents the discretized gas dynamic equations directly on the cell size and time step scales, i.e., the so-called direct modeling method. As a result, the scheme is able to capture the cross-scale flow physics from particle transport to hydrodynamic wave propagation, and provides a continuous variation of solutions from the Boltzmann to the Euler equations. Different from conventional DSMC-Fluid hybrid method, the AUGKS does not need a buffer zone to match up kinetic and hydrodynamic solutions. Instead, continuous and discrete particle velocity spaces are automatically and robustly switched, such as translating the continuous Chapman-Enskog distribution function to the discrete grid points in the velocity space. Therefore, the AUGKS is feasible for the numerical simulations with unsteadiness and complex geometries. Compared with the asymptotic preserving (AP) method which solves kinetic equation uniformly over entire computational domain with discretized velocity space, the current velocity-space adaptive unified scheme speeds up the computation, reduces the memory requirement significantly, and maintains the equivalent accuracy for multiscale flow simulations. Many test cases validate the current approach. The AUGKS provides an effective tool for non-equilibrium flow studies.