Transient Region Research Articles

Creep Deformation Behaviour and its Effect on Creep Life and Rupture Ductility of W-Mo-balanced 9Cr Steels

ABSTRACTThe creep deformation behaviour and its effect on the creep life and rupture ductility are investigated for W-Mo-balanced 9Cr steels at 600 °C to 700 °C. The creep life is described as tr = 1.5/[min (dln/d)], where min and dln/d reflect the creep deformation behaviour in the transient and acceleration creep regions, respectively. The creep life is also correlated with the time to minimum creep rate tm as tr = gtm, where g slightly increases with decreasing stress. The logarithm of creep rate linearly increases with strain in the initial stage of acceleration creep region. This is followed by a decrease in dlnd with strain at high stresses, resulting in ductile failure at large strains, while it is followed by an increase in dln/d with strain at low stresses, resulting in rupture at small strains.

Characterization of crack propagation behavior in Al-7075 under in-plane biaxial fatigue loading with shear overloads

Effect of shear overloads in an otherwise constant amplitude, tensile biaxial fatigue loading is investigated using a cruciform specimen of Al 7075-T651, and the crack propagation behavior and governing micromechanisms are characterized. It was observed that with an increase in shear overload ratio fatigue life of the specimen is increased and the crack growth rate is significantly affected. This behavior is attributed to the combined effects of competing mechanisms including compressive residual stress, plasticity induced crack closure, and strain hardening. The fractographic study revealed features of shear fracture in the transient region and tensile fracture in the pre-overload region and post-overload region.

Assessment of ionospheric variability from IRI-2016, SPIM-2017, and IGS-GIM using Digisonde and GPS observations over Cyprus

The present study focuses on ionospheric F-layer critical parameters (foF2/hmF2) and Total Electron Content (TEC) by exploiting a long-term data (2009 to 2016) from Digisonde and Global Positioning System (GPS) receiver observations over a lower-middle latitude European location Nicosia, Cyprus (geographic 35° N, 33° E; magnetic dip. 32° N). Also, it adheres to evaluating the performances of global empirical standard International Reference Ionosphere (IRI-2016), Standard Plasmasphere Ionosphere Model (SPIM-2017/IRI-Plas 2017), and interpolated TEC from the IGS-Global Ionospheric Maps (GIMs) by comparing with the Digisonde and GPS observations. Our results confirm a noteworthy departure of estimated foF2/hmF2 and TEC in SPIM-2017, even larger than that of IRI-2016 as regards to the Digisonde and GPS observations, irrespective of season, solar activity, and geomagnetic activity conditions. This contradicts the general perception on an ideal behavior of the empirical climatological model over the middle latitude region, inferring that the transient region between the low and middle latitude does suffer from noticeable uncertainties. Also, we did not notice any convincing response of the storm sub-model in IRI except a rare flipping in its magnitude and absolutely no alteration in SPIM model estimations to the onset of geomagnetic storms over the region despite the storm sub-model was kept ‘on’. This suggests a revisit into the underlying storm sub-model database in the models. Interestingly, the ingestion of Digisonde recorded foF2/hmF2 and GPS-TEC into the SPIM-2017 model results in a remarkable convergence of the parameters towards the local observations even during active geomagnetic storm conditions. It ascertains the flexibility in SPIM-2017 towards plausible improvements in the model estimations by ingesting GPS-TEC. Above all, such a scheme is in line with efforts towards reliable ionospheric error mitigations in navigation, communication, and satellite applications.

Generalized hydrodynamic approach to charge and energy currents in the one-dimensional Hubbard model

We have studied nonequilibrium dynamics of the one-dimensional Hubbard model using the generalized hydrodynamic theory. We mainly investigated the spatiotemporal profile of particle density (equivalent to charge density), energy density, and their currents using the partitioning protocol; the initial state consists of two semi-infinite different thermal equilibrium states joined at the origin. In this protocol, a transient region where currents flow appears around the origin, and this region expands its size linearly with time. We examined how density and current profiles depend on initial conditions. Inside the transient region, we have found a clogged region where charge current is zero but nonvanishing energy current flows. This phenomenon is similar to spin-charge separation in Tomonaga-Luttinger liquids, in which spin and charge excitations propagate with different velocities. This region appears when one of the initial states has half-filled electron density, and it is located adjacent to this initial state. We have proved analytically the existence of the clogged region in the infinite temperature case of the half-filled initial state. The existence is confirmed also for finite temperatures by numerical calculations of generalized hydrodynamics. A similar analytical proof is also given for a clogged region of spin current when magnetic field is applied to one and only one of the two initial states. A universal proportionality of charge and spin currents is also proved for a special region, for general initial conditions of electron density and magnetic field. To examine the clogged region of charge current, we have calculated the current contributions of different types of quasiparticles in the Hubbard model. It is found that the charge current component carried by scattering states (i.e., Fermi liquid type) is canceled completely in the clogged region by the counter flows carried by bound-state quasiparticles (called $k\text{\ensuremath{-}}\mathrm{\ensuremath{\Lambda}}$ strings). Their contributions are not canceled for energy current, which is also proved analytically for special cases, and these different behaviors are the origin of the clogged region. Except for the clogged region, charge and energy densities are in good proportion to each other, and their ratio depends on the initial conditions. This proportionality, in nonequilibrium dynamics, is reminiscent of Wiedemann-Franz law in thermal equilibrium, which states current proportionality determined by temperature. The long-time stationary values of charge and energy currents were also studied with varying initial conditions. We have compared the results with the values of noninteracting systems and discussed the effects of electron correlations. The ratio of these stationary currents is also analyzed. We have found that the temperature dependence of the ratio is strongly suppressed by electron correlations and even reversed.

An investigation on the effect of the wall treatments in RANS simulations of model and full-scale marine propeller flows

A numerical analysis is carried out for the marine propellers in open water conditions to investigate the effect of the wall treatments in model and full scale. The standard wall function to apply the low of the wall and the two layer zonal model to calculate the whole boundary layer for a transition phenomenon are used with one turbulence model. To determine an appropriate distance of the first grid point from the wall when using the wall function, a formula based on Reynolds number is suggested, which can estimate the maximum y+ satisfying the logarithmic law. In the model scale, it is confirmed that a transition calculation is required for a model scale propeller with low Reynolds number that the transient region appears widely. While in the full scale, the wall function calculation is recommended for efficient calculations due to the turbulence dominant flow for large Reynolds number.

Error minimization of positive output luo converter using various optimization techniques

DC-DC converters are widely used in many consumer electronic devices such as computers, medical equipment, battery chargers, cellular phones and many Industrial drives. These electronic devices require different voltage levels which is supplied from battery or some external supply. In multiple battery mission voltage decays as its stored energy is drained and requires large saving space. The switched DC-DC converters overcome these drawbacks and also regulate the output voltage for different power levels efficiently. This paper elaborates the structure of Luo converter with optimized PI controller. Positive Output Elementary Luo Converter (POELC) is designed for boost operation by choosing the appropriate duty cycle. The PI controller parameters are optimized using Cuckoo and Crow search algorithms. The proposed control methods are investigated for the transient and steady state region. The sensitivity of these controllers to supply load and line disturbances are also studied along with the servo response are presented. The controller incorporates a Luo converter is evaluated in terms of Integral Time Square Error (ITSE) and Integral Time Absolute Error. Dynamic modelling of the power converter is derived by using state space averaging method. The simulation model of the Luo converter with its control circuit is implemented in MATLAB/SIMULINK. Experimental result shows that Cuckoo PI controller has significantly performance improvement in comparison with both the conventional and Crow PI controller.

Effect of source-drain conduction in single-event transient on nanoscaled bulk fin field effect transistor

Fin field effect transistor (FinFET) is a most widely used structure when the field effect transistor is scaled down to 30 nm or less. And there are few studies on single-event transient of FinFET devices with gate length below 30 nm. The single-event-transient on FinFET with gate length below 30 nm is worth studying. The single-event-transient responses of bulk FinFETs with 30 nm, 40 nm, 60 nm and 100 nm gate length are examined by using the pulsed laser and technology computer-aided design (TCAD) simulation in this article. First, we use the pulsed laser to ionize the gate of the FinFET device and detect the transient drain current of the FinFET device. The experimental results show that there are obvious platforms for the transient drain current tails of FinFETs with different gate lengths, and the platform current increases as the gate length of FinFET becomes shorter. The charges collected in the platform of FinFET devices with gate lengths of 100, 60, 40, and 30 nm are 34%, 40%, 51%, and 65% of the total charge collected in transient drain current, respectively. Therefore, when the FinFET device with the gate length below 100 nm, the platform current will seriously affect the device performance. Second, we use TCAD to simulate the heavy ion single-event effect of FinFET device and study the generation mechanism of platform region in transient drain current. The TCAD simulation explains this mechanism. Laser or heavy ions ionize high concentration electron-hole pairs in the device. The holes are quickly collected and the high concentration electrons are left under the FinFET channel. High concentration electrons conduct source and drain, generating the source-to-drain current at the tail of the transient drain current. Moreover the source-drain conduction enhances the electrostatic potential below the FinFET channel and suppresses high-concentration electron diffusion, making source-to-drain current decrease slowly and form the platform. The transient drain current tail has a long duration and a large quantity of collected charges, which seriously affects FinFET performance. This is a problem that needs studying in the single-event effect of FinFET device. It is also a problem difficult to solve when the FinFET devices are applied to spacecraft. And the generation mechanism of the transient drain current plateau region of FinFET device can provide theoretical guidance for solving these problems.

Seepage Analysis on the Surface Layer of Multistage Filled Slope with Rainfall Infiltration

Based on the theory of rainfall infiltration, the surface infiltration model of multilevel filled slope was established by using the SEEP/W module of GeoStudio. The changes of the volumetric water content (VWC) and pore water pressure (PWP) in the surface of the slope during the rainfall infiltration were analyzed, and the influence of the change of the rainfall conditions on the VWC and PWP was considered. The analysis showed that VWC and PWP increased when the rain fell, and the growth rate of the higher feature point was higher. The affected area was concentrated on the upper part of the surface about 0.75 m. With the increasing of rainfall intensity, the slope surface getting to transient saturation state was quick, and the time of the PWP increasing to 0 among the feature points of same elevation was shortened. Meanwhile, the PWP presented a positive value, and as the infiltration depth increased, the transient saturation region expanded. The safety coefficient of the multistage filled slope was continuously reduced; after the stop of rainfall, the VWC and the PWP decreased, and the decline rate of the higher feature points was higher. In addition, the PWP of the lower part increased, and the safety factor of the slope presented a trend of rebound.

Seasonal Variations of Arctic Low-Level Clouds and Its Linkage to Sea Ice Seasonal Variations.

Using CALIPSO‐CloudSat‐Clouds and the Earth's Radiant Energy System‐Moderate Resolution Imaging Spectrometer data set, this study documents the seasonal variation of sea ice, cloud, and atmospheric properties in the Arctic (70°N–82°N) for 2007–2010. A surface‐type stratification—consisting Permanent Ocean, Land, Permanent Ice, and Transient Sea Ice—is used to investigate the influence of surface type on low‐level Arctic cloud liquid water path (LWP) seasonality. The results show significant variations in the Arctic low‐level cloud LWP by surface type linked to differences in thermodynamic state. Subdividing the Transient Ice region (seasonal sea ice zone) by melt/freeze season onset dates reveals a complex influence of sea ice variations on low cloud LWP seasonality. We find that lower tropospheric stability is the primary factor affecting the seasonality of cloud LWP. Our results suggest that variations in sea ice melt/freeze onset have a significant influence on the seasonality of low‐level cloud LWP by modulating the lower tropospheric thermal structure and not by modifying the surface evaporation rate in late spring and midsummer. We find no significant dependence of the May low‐level cloud LWP peak on the melt/freeze onset dates, whereas and September/October low‐level cloud LWP maximum shifts later in the season for earlier melt/later freeze onset regions. The Arctic low cloud LWP seasonality is controlled by several surface‐atmosphere interaction processes; the importance of each varies seasonally due to the thermodynamic properties of sea ice. Our results demonstrate that when analyzing Arctic cloud‐sea ice interactions, a seasonal perspective is critical.

Global Geometric Structure of the Transient Stability Regions of Power Systems

In this paper, a novel qualitative method is proposed to analyze the transient stability of power systems. Unlike the traditional methods, this method can illustrate the structural characteristics of the stability region and display the boundary on the global phase plane intuitively. Particularly, the stability boundary and phase portraits are investigated in three-dimensional space. Global phase portraits including the singularity at infinity (SAI) show the beginning and ending points of the portraits, and indicate the whole situation of an attractor's basin. To properly use the method to clarify the dynamic behavior at infinity, the multi-machine system is simplified by an equivalent method and the trajectories of the rotor angle near the unstable equilibrium point are projected into a closed ball based on the invariant submanifolds. The effects of damping coefficient, fault locations, and fault types on the transient stability region are discussed by the coordinate of the SAI, which are obtained based on the qualitative theory of differential equations. If the traditional generators are replaced with the distributed energy resources, the transient stability of the power system may be affected both positively and negatively. The simulation experiments of the IEEE 39-bus test system are carried out to validate the effectiveness of the proposed method.

The Nature and Frequency of Outer Retinal Disruption in Idiopathic Multifocal Choroiditis Associated With Persistent Fundus Hyperautofluorescence.

To describe the prevalence and anatomic correlates for hyperautofluorescence related to outer retinal disruption in eyes with multifocal choroiditis (MFC). Retrospective review of MFC patients. Fifty-nine eyes from 37 patients were analyzed. Multimodal imaging was utilized to identify nine eyes (15.2%) of six patients with either transient (Group 1) or persistent (Group 2) regions of hyperautofluorescence associated with ellipsoid zone (EZ) disruption over intact retinal pigment epithelium (RPE). Group 1 included four eyes (6.8%) of three patients in which the hyperautofluorescence and EZ loss resolved within a few months (range: 28 days to 125 days) and had intact overlying outer nuclear (ONL) and outer plexiform layers (OPL) (mean follow-up: 1.3 years). Group 2 included five eyes (8.5%) of three patients with regions of permanent EZ disruption associated with absent or reduced ONL and OPL (mean follow-up: 4.6 years). Hyperautofluorescence correlating with EZ disruption over intact RPE is a rare occurrence in MFC. Evaluating outer retinal integrity by optical coherence tomography may help identify eyes with potential for EZ restoration, which may have implications regarding treatment strategies. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:675-683.].

Reconfigurable Range-Doppler Processing and Range Resolution Improvement for FMCW Radar

A reconfigurable range-Doppler processing method for FMCW radar is presented. By concatenating beat-frequency signals from more than one sweep, a continuous beat-frequency signal for the whole coherent processing interval (CPI) can be created. As a result, continuous targets’ observation time is extended beyond that of a single chirp duration, leading to range resolution improvement. The created continuous beat-frequency signal can be split in the digital domain to any two-dimensional slow-time and fast-time matrices with the same number of elements as in the original signals, which offers a realization of a software-defined pulse/sweep repetition rate in range-Doppler processing. The signal concatenation is done in the short-time Fourier transform (STFT) domain, where the beat-frequency slices are extrapolated to compensate for the observation time lost in the transient region between sweeps, and then a phase correction is applied to each frequency-slice as appropriate, followed by an inverse STFT (ISTFT). The proposed technique is verified with simulation and experiments with an FMCW radar for stable and moving target scenarios. We found that the method allows for range resolution improvement without the transmission of additional bandwidth and also allows for the ability to observe different resolution granularities in parallel from one CPI. It additionally allows the decoupling of the transmitted PRF from the Doppler processing PRF, permitting the facility to observe different unambiguous Doppler velocity intervals from one CPI, without compromising on the total CPI processing gain.

Compare numerical modeling and improved understanding of dynamic sessile drop contact angle analysis in Liquid-Solid-Gas system

Dynamic contact angle measurement; as a standard method for surface wettability analysis, is usually conducted through the analysis of sessile drops formed following the low rate injection of fluid from beneath through a drilled hole via an injection needle. However, understanding/characterizing the changes of drop contact angle from the point where the flat solid surface begins is not well discussed yet. Moreover, during the evaluation of size-dependent behavior of contact angle of millimeter-scale drops, the effect of the drilled hole is ignored. In this regard, in the current study, the experimental and thermodynamic characterizations of the sessile drop advancing contact angle measurements for a liquid-solid-air system are presented. To do this, a set of dynamic contact angle experiments for a water-calcite-air system with different devised hole diameters and roughness is conducted, and Gibbs free energy analysis is then utilized to propose a modeling scheme. Experimental results revealed a transient region from zero infinite contact angle at the hole to infinite contact angle of the solid surface, which was equal to 74.61° and 69.05° for nanoscale, and microscale surface roughness. In addition, it was shown that with a decrease in the hole diameter, the transient region met a lower value of contact angle at different dimensionless volumes. The result of higher advancing contact angle measured for the system with smaller drilled hole diameter was attributed to higher contact-line velocity. However, the assumption of low rate advancing contact angle was not violated for the hole diameter larger than 1.4 mm. Numerical studies demonstrated that in the case of zero line tension, two straight lines with positive slop could be fitted to the data; attributed to drilled hole effect. Besides, it was concluded that this behavior should not be interpreted as a negative line tension effect. The obtained values of line tension and equilibrium advancing contact angle, as matching parameters, were in agreement with those reported in the previous studies. Results of this work could help for better analyzing the size-dependent behavior of millimeter-scale drop through a suggested size-dependent model.

Transient amplification characteristics of frequency modulated wave in semiconductor plasmas

We perform an analytical investigation of modulational interaction of an electromagnetic pump wave in a transversely magnetized weakly polar semiconductor plasma medium. Based on the hydrodynamic model, a critical examination of frequency modulational amplification is made in a moderately doped III–V semiconductor crystal (n-GaAs) duly shined by pulsed 10.6 µm CO2 laser. The effect of electron-LO phonon interaction and coupled magnetoplasma excitations on the nonlinear interaction of a laser beam adds new dimension to the analysis. Steady state and transient gain coefficients, threshold pump intensity and optimum-pulse duration for the onset of modulational instability are estimated. The paper concentrates on the study of gain characteristics mainly in transient region. Effect of doping and applied magnetic field on the threshold pump intensity and growth rate has been significantly analysed. Graphical analysis interprets strong dependence of transient amplification characteristics on these parameters. So a judicious choice of physical parameters may develop growth at much lower pump intensity improving the cost effectiveness of the system. These results may help to be important for understanding and improving the performance of modulator.

Experimental observation and simulation of the equilibration of electron swarms in a scanning drift tube

We investigate the spatially and temporally resolved electron kinetics in a homogeneous electric field in argon gas, in the vicinity of an emitting boundary. This (transient) region, where the electron swarm exhibits non-equilibrium character with energy gain and loss processes taking place at separate positions (in space and time), is monitored experimentally in a scanning drift tube apparatus. Depending on the strength of the reduced electric field we observe the equilibration of the swarm over different length scales, beyond which the energy gain and loss mechanism becomes locally balanced and transport properties become spatially invariant. The evolution of the electron swarm in the experimental apparatus is also described by Monte Carlo simulations, of which the results are in good agreement with the experimental observations, over the domains of the reduced electric field and the gas pressure covered.

Microstructure and Microhardness of Powder Boronized Vanadis 6 Steel

A Cr-V ledeburitic steel Vanadis 6 was powder boronized for different durations, austenitized, quenched and tempered. All the boronized layers are two-phased, i.e. they are formed by MeB and Me2B compounds. The thickness of boronized compound layers increased moderately with boronizing time. The thickness of MeB individual layer increases more rapidly, and it makes up to 50% of total layer thickness when boronized for 150 min. Boronized layers contain enhanced amount of chromium but they are almost free of other alloying elements. The MeB compound has a microhardness of around 1860 HV 0.1 after short – time boronizing but its microhardness exceeded 2100 HV 0.1 after long – time processing. The microhardness of Me2B was correspondingly lower, its values were around 1760 – 1850 HV 0.1. Transient region manifested enhanced amount of carbides, resulting from carbon transport from growing boronized layers towards the substrate. This phenomenon was reflected in elevated hardness compared to the substrate.

Numerical Errors in Unsteady Flow Simulations

This article discusses numerical errors in unsteady flow simulations, which may include round-off, statistical, iterative, and time and space discretization errors. The estimation of iterative and discretization errors and the influence of the initial condition on unsteady flows that become periodic are discussed. In this latter case, the goal is to determine the simulation time required to reduce the influence of the initial condition to negligible levels. Two one-dimensional, unsteady manufactured solutions are used to illustrate the interference between the different types of numerical errors. One solution is periodic and the other includes a transient region before it reaches a steady-state. The results show that for a selected grid and time-step, statistical convergence of the periodic solution may be achieved at significant lower error levels than those of iterative and discretization errors. However, statistical convergence deteriorates when iterative convergence criteria become less demanding, grids are refined, and Courant number increased.For statistically converged solutions of the periodic flow and for the transient solution, iterative convergence criteria required to obtain a negligible influence of the iterative error when compared to the discretization error are more strict than typical values found in the open literature. More demanding criteria are required when the grid is refined and/or the Courant number is increased. When the numerical error is dominated by the iterative error, it is pointless to refine the grid and/or reduce the time-step. For solutions with a numerical error dominated by the discretization error, three different techniques are applied to illustrate how the discretization uncertainty can be estimated, using grid/time refinement studies: three data points at a fixed Courant number; five data points involving three time steps for the same grid and three grids for the same time-step; five data points including at least two grids and two time steps. The latter two techniques distinguish between space and time convergence, whereas the first one combines the effect of the two discretization errors.

Wear of Electroplated Super Abrasive CBN Wheel during Grinding of Inconel 718 Super Alloy

In the present work, the wear of monolayer electroplated cubic boron nitride wheel during grinding of Inconel 718 super alloy is investigated, and the influence of wear process on wheel topography is reported. The radial wear of the wheel was characterized by an early transient state followed by a steady state wear regime and finally a steel rise in wear rate. The initial transient region progressed up to radial wear of 21 μm. During the steady state region, the radial wear was in the range of 21 μm to 25.5 μm. Beyond the steady state region, there was a sudden increase of 8.5 μm radial wear depicting the progress of wear towards the failure region. The normal and tangential forces remained approximately constant up to about 21 μm wheel wear, and subsequently progressively increased to a maximum of 34 μm wear. The specific energy began approximately at about u = 240 J/mm3 and started progressing beyond radial wear of 21 μm and increased up to 540 J/mm3 at the wear of 34 μm. There was high initial roughness value with the fresh wheel with a progressive decrease with continued grinding due to the increase in active grains.

(Invited) Time Resolved Spectroscopy of Charge Carriers in TiO2 Anatase and Rutile Single Crystals. Effect of Oxygen Defects and Electrons/Holes Scavengers

In an effort to probe into the fundamentals of charge carriers dynamics relevant to photo-catalytic materials, we have performed femtosecond time resolved spectroscopy (TRS) on anatase and rutile single crystals in the gas phase as well as in aqueous environment. By studying the effect of pump fluence, differences in charge carrier recombination rates and nature between both crystals were observed. The time constants for carrier recombination are two orders of magnitude slower for anatase (101) when compared to those of rutile (110) single crystal. Bulk defects introduced by sample reduction via annealing in ultra-high vacuum resulted in faster recombination rates for both polymorphs. Both surfaces (fresh and reduced) probed by pump fluence dependence measurements revealed that the major recombination channel in fresh and reduced anatase and reduced rutile is the first-order Shockley–Reed mediated. The effect of a hole trapping agent (ethanol) and of electron trapping agents (Ag+ and Ce4+ cations) is investigated over TiO2(110) rutile single crystal. Ethanol adsorption resulted in increasing the transient absorption signal in the 700-950nm with a slight decrease of their lifetime. No change was seen in the 500nm region commonly attributed to the presence of holes. The decay of the 700-950 nm signal mainly composed of two components is considerably perturbed by the presence of Ag+ or Ce4+ cations, which may indicate its surface origin. Work in progress to extract kinetic information from the study of the concentration effect of these metal cations in both the “nominally” hole and electron transient absorption regions.

Adaptive numerical homogenization for upscaling single phase flow and transport

We propose an adaptive multiscale method to improve the efficiency and the accuracy of numerical computations by combining numerical homogenization and domain decomposition for modeling flow and transport. Our approach focuses on minimizing the use of fine scale properties associated with advection and diffusion/dispersion. Here a fine scale flow and transport problem is solved in subdomains defined by a transient region where spatial changes in transported species concentrations are large while a coarse scale problem is solved in the remaining subdomains. Away from the transient region, effective macroscopic properties are obtained using local numerical homogenization. An Enhanced Velocity Mixed Finite Element Method (EVMFEM) as a domain decomposition scheme is used to couple these coarse and fine subdomains [1]. Specifically, homogenization is employed here only when coarse and fine scale problems can be decoupled to extract temporal invariants in the form of effective parameters. In this paper, a number of numerical tests are presented for demonstrating the capabilities of this adaptive numerical homogenization approach in upscaling flow and transport in heterogeneous porous medium.