Showing papers on "Convection published in 2002"

The Boreal Summer Intraseasonal Oscillation: Relationship between Northward and Eastward Movement of Convection

Abstract: The summertime intraseasonal oscillation (ISO) is an important component of the south Asian monsoon. Lagged regressions of intraseasonally filtered (25‐80 days) outgoing longwave radiation (OLR) reveal that centers of convection move both northward and eastward from the central equatorial Indian Ocean subsequent to the initiation of an ISO. Eastward movement of convection is also seen at Indian subcontinent latitudes (10 8‐208N). Based on the regression results, the summertime ISO convection signal appears as a band tilting northwestward with latitude and stretching from the equator to about 208N. Viewed along any meridian, convection appears to propagate northward while equatorial convection propagates to the east. To examine the robustness of the connection between eastward and northward movement, individual ISOs are categorized and composited relative to the strength of the large-scale eastward component of convection in the central equatorial Indian Ocean. It is found that the majority of ISOs that exhibit northward movement onto the Indian subcontinent (42 out of 54 ISOs, or 78%) also exhibit eastward movement into the western Pacific Ocean. It is also found that when convection in the central Indian Ocean is not followed within 10‐20 days by convection in the western Pacific Ocean (12 out of 54 ISOs, or 22%), the independent northward movement of convection in the Indian Ocean region is somewhat stunted. The link between the eastward and northward movement of convection is consistent with an interpretation of the summertime ISO in terms of propagating equatorial modes. The northward moving portion of convection is forced by surface frictional convergence into the low pressure center of the Rossby cell that is excited by equatorial ISO convection. A similar convergence pattern is seen for the northern winter ISO, but it does not generate poleward movement due to relatively cool SSTs underlying the surface convergence.

Differences in heat budgets of the near-surface Arabian Sea and Bay of Bengal: Implications for the summer monsoon

Abstract: An analysis of the heat budgets of the near-surface Arabian Sea and Bay of Bengal shows significant differences between them during the summer monsoon (June-September). In the Arabian Sea the winds associated with the summer monsoon are stronger and favor the transfer of heat to deeper layers owing to overturning and turbulent mixing. In contrast, the weaker winds over the bay force a relatively sluggish oceanic circulation that is unable to overturn, forcing a heat budget balance between the surface fluxes and diffusion and the rate of change of heat in the near-surface layer. The weak winds are also unable to overcome the strong near-surface stratification because of a low-salinity surface layer. This leads to a shallow surface mixed layer that is stable and responds quickly to changes in the atmosphere. An implication is that sea surface temperature (SST) in the bay remains higher than 28°C, thereby supporting large-scale deep convection in the atmosphere during the summer monsoon. The atmospheric heating associated with the convection plays a critical role in sustaining the monsoon winds, and the rainfall associated with it, not only over the bay but also over the Indian subcontinent, maintains a low-salinity surface layer. In the Arabian Sea the strong overturning and mixing lead to lower SST and weak convective activity, which in turn, lead to low rainfall and runoff, resulting in weak stratification that can be overcome easily by the strong monsoon winds. Thus, in both basins, there is a cycle with positive feedback, but the cycles work in opposite directions. This locks monsoon convective activity primarily to the bay.

Turbulent Convection under the Influence of Rotation: Sustaining a Strong Differential Rotation

Abstract: The intense turbulence present in the solar convection zone is a major challenge to both theory and simulation as one tries to understand the origins of the striking differential rotation profile with radius and latitude that has been revealed by helioseismology. The differential rotation must be an essential element in the operation of the solar magnetic dynamo and its cycles of activity, yet there are many aspects of the interplay between convection, rotation, and magnetic fields that are still unclear. We have here carried out a series of three-dimensional numerical simulations of turbulent convection within deep spherical shells using our anelastic spherical harmonic (ASH) code on massively parallel supercomputers. These studies of the global dynamics of the solar convection zone concentrate on how the differential rotation and meridional circulation are established. We have addressed two issues raised by previous simulations with ASH. First, can solutions be obtained that possess the apparent solar property that the angular velocity Ω continues to decrease significantly with latitude as the pole is approached? Prior simulations had most of their rotational slowing with latitude confined to the interval from the equator to about 45°. Second, can a strong latitudinal angular velocity contrast ΔΩ be sustained as the convection becomes increasingly more complex and turbulent? There was a tendency for ΔΩ to diminish in some of the turbulent solutions that also required the emerging energy flux to be invariant with latitude. In responding to these questions, five cases of increasingly turbulent convection coupled with rotation have been studied along two paths in parameter space. We have achieved in one case the slow pole behavior comparable to that deduced from helioseismology and have retained in our more turbulent simulations a consistently strong ΔΩ. We have analyzed the transport of angular momentum in establishing such differential rotation and clarified the roles played by Reynolds stresses and the meridional circulation in this process. We have found that the Reynolds stresses are crucial in transporting angular momentum toward the equator. The effects of baroclinicity (thermal wind) have been found to have a modest role in the resulting mean zonal flows. The simulations have produced differential rotation profiles within the bulk of the convection zone that make reasonable contact with ones inferred from helioseismic inversions, namely, possessing a fast equator, an angular velocity difference of about 30% from equator to pole, and some constancy along radial lines at midlatitudes. Future studies must address the implications of the tachocline at the base of the convection zone, and the near-surface shear layer, on that differential rotation.

Convection and restratification in the Labrador Sea, 1990-2000

Abstract: Temperature, salinity and other property distributions observed across the central Labrador Sea in the early summers between 1990 and 2000 reveal a 4-year period of exceptionally intense convection followed by 5 years of restratification. The intense convection led, in the centre of the Sea, to mixed layers increasing in density and depth to a maximum of 2300 m thereby creating a fresh deep pool of Labrador Sea Water (LSW). In the second half of the decade, warmer winter weather limited the depth of convection to ∼1000 m. The shallower convection isolated the deep reservoir of homogeneous LSW between 1000 and 2000 m from renewal: this reservoir slowly diminished in volume as the layer became more stratified. In addition, the mean temperature and salinity of the 1000–2000 m layer increased by 0.4°C and 0.025 as warmer more saline water was mixed into the central region from the boundaries. In the upper layer between 150 and 1000 m the restratification processes led to an increase in temperature of 0.6°C but no significant change in salinity. The upper 150 m also showed no discernible trends in salinity but did participate in the warming trend. Interannual variability in local atmospheric forcing accounts for much of the observed change in heat content in the convectively overturned part of the water column during both the convection and restratification phases. It is proposed that constant horizontal fluxes transport heat and salt from the boundaries into the centre of the Sea. When the heat loss from the sea surface is greater than the horizontal flux the mixed layer becomes colder and denser and the depth of convection increases. When the heat loss is less than the horizontal flux and the convection remains shallow the temperature rises in both the 0–1000 m and the 1000–2000 m layers and salinity increases in the deeper layer. In both situations salinity in the upper 1000 m remains roughly constant as the horizontal salinity flux approximately offsets the annual input of fresh water of 60±10 cm into the surface layer.

Distribution and influence of convection in the tropical tropopause region

Abstract: [1] A global analysis of convective cloud in the tropical tropopause region (12–17 km) is presented. The analysis is based on high-resolution global imagery of cloud brightness temperatures from satellites and from contemporaneous reanalysis temperatures. The coverage by deep convection decreases nearly exponentially with increasing altitude in the tropopause region. Convection is found at temperatures colder than the tropical cold point tropopause over 0.5% (±0.25%) of the tropics. Convection rarely penetrates more than 1.5 km above the tropopause. Large-scale relationships between cold tropopause temperatures and deep convection indicate that where the tropopause is coldest convection penetrates most frequently. Small-scale relationships show that the coldest diurnal tropopause temperatures occur after the diurnal peak in deep convection at tropopause levels over land. The coverage by deep convection is used to estimate the mass exchange or turnover time due to convection in the tropopause region. This turnover time is of the order of weeks at 12 km but increases to longer than a year at 18 km, with significant uncertainties in the tropopause region. INDEX TERMS: 3314 Meteorology and Atmospheric Dynamics: Convective processes; 3362 Meteorology and Atmospheric Dynamics: Stratosphere/ troposphere interactions; 0341 Atmospheric Composition and Structure: Middle atmosphereconstituent transport and chemistry (3334); KEYWORDS: tropical convection, stratospheretroposphere exchange

Measurement of interstitial convective heat transfer and frictional drag for flow across metal foams

Abstract: Convective heat transfer and friction drag in a duct inserted with aluminum foams have been studied experimentally. The combined effects of foam porosity (e=0.7, 0.8, and 0.95) and flow Reynolds number (1900≤Re≤7800) are examined. Frictional drags for flow across the aluminum foam are measured by pressure taps, while interstitial heat transfer coefficients in the aluminum foam are determined using a transient single-blow technique with a thermal non-equilibrium two-equation model. Solid material temperature distribution is further measured for double check of the heat transfer results. To understand the frictional drag mechanisms, smoke-wire flow visualization is conducted in the aluminum-foam ducts. Results show that both the friction factor and the volumetric heat transfer coefficient increase with decreasing the foam porosity at a fixed Reynolds number. In addition, the aluminum foam of e=0.8 has the best thermal performance under the same pumping power constraint among the three aluminum foams investigated. Finally, empirical correlations for pore Nusselt number are developed in terms of pore Reynolds number under various foam porosities

Evidence for Strengthening of the Tropical General Circulation in the 1990s

Abstract: Satellite observations suggest that the thermal radiation emitted by Earth to space increased by more than 5 watts per square meter, while reflected sunlight decreased by less than 2 watts per square meter, in the tropics over the period 1985-2000, with most of the increase occurring after 1990 By analyzing temporal changes in the frequency of occurrence of emitted thermal and reflected solar fluxes, the effects of El Nino-Southern Oscillation are minimized, and an independent longer-time-scale variation of the radiation budget is identified Similar analyses of upper tropospheric humidity, cloud amount, surface air temperature, and vertical velocity confirm that these flux changes are associated with a decadal-time-scale strengthening of the tropical Hadley and Walker circulations Equatorial convective regions have intensified in upward motion and moistened, while both the equatorial and subtropical subsidence regions have become drier and less cloudy

Zonal flow driven by strongly supercritical convection in rotating spherical shells

Abstract: Thermal convection in a rotating spherical shell with free-slip boundaries can excite a dominant mean zonal flow in the form of differentially rotating cylinders concentric to the principal rotation axis. This process is studied numerically for Prandtl numbers of order 1, Ekman numbers in the range E = 3 x 10 -4 -10 -5 , and Rayleigh numbers up to 100× critical. Small-scale convection transfers kinetic energy into the mean zonal flow via Reynolds stresses. For low Ekman number and high Rayleigh number, the force balance is predominantly among the Coriolis, inertial and buoyancy forces, and viscosity plays a minor role. A modified Rayleigh number Ra* is introduced, which does not depend on viscosity or thermal diffusivity, and asymptotic scaling laws for the dependence of various properties on Ra* in the limit of negligible viscosity (E → 0) are estimated from the numerical results. The ratio of kinetic energy in the zonal flow to that in the non-zonal (convective) flow increases strongly with Ra* at low supercritical Rayleigh number, but drops at high values of Ra*. This is probably caused by the gradual loss of geostrophy of the convective columns and a corresponding decorrelation of Reynolds stresses. Applying the scaling laws to convection in the molecular hydrogen envelopes of the large gas planets predicts the observed magnitude of the zonal winds at their surfaces.

Hydrography of the Labrador Sea during Active Convection

Abstract: The hydrographic structure of the Labrador Sea during wintertime convection is described. The cruise, part of the Deep Convection Experiment, took place in February‐March 1997 amidst an extended period of strong forcing in an otherwise moderate winter. Because the water column was preconditioned by previous strong winters, the limited forcing was enough to cause convection to approximately 1500 m. The change in heat storage along a transbasin section, relative to an occupation done the previous October, gives an average heat loss that is consistent with calibrated National Centers for Environmental Prediction surface heat fluxes over that time period (; 200 Wm 22). Deep overturning was observed both seaward of the western continental slope (which was expected), as well as within the western boundary current itself—something that had not been directly observed previously. These two geographical regions, separated by roughly the 3000-m isobath, produce separate water mass products. The offshore water mass is the familiar cold/fresh/dense classical Labrador Sea Water (LSW). The boundary current water mass is a somewhat warmer, saltier, lighter vintage of classical LSW (though in the far field it would be difficult to distinguish these products). The offshore product was formed within the cyclonic recirculating gyre measured by Lavender et al. in a region that is limited to the north, most likely by an eddy flux of buoyant water from the eastern boundary current. The velocity measurements taken during the cruise provide a transport estimate of the boundary current ‘‘throughput’’ and offshore ‘‘recirculation.’’ Finally, the overall trends in stratification of the observed mixed layers are described.

Convective flows in rapidly rotating spheres and their dynamo action

Abstract: The present understanding of convection in rotating spherical fluid shells is reviewed and some recent results on coherent structures and magnetic field generation are considered in detail. The constraints exerted by the Coriolis force leads to unusual properties not found in nonrotating systems, such as vacillations, localized convection, and chaotic relaxation oscillations. The central role played by the differential rotation generated by the Reynolds stress of convection in the case of Prandtl numbers of the order unity or less is emphasized. Magnetic fields generated through the dynamo process offer new degrees of freedom. Through the braking of the differential rotation the Lorentz force contributes to an enhanced heat transport.

Penetration and Overshooting in Turbulent Compressible Convection

Abstract: We present the results of a series of high-resolution, three-dimensional numerical experiments that investigate the nature of turbulent compressible convective motions extending from a convection zone into a stable layer below In such convection, converging flows in the near-surface cellular convecting network create strong downflowing plumes that can traverse the multiple scale heights of the convection zone Such structures can continue their downward motions beyond the convecting region, piercing the stable layer, where they are decelerated by buoyancy braking If these motions mix entropy to an adiabatic state below the convection zone, the process is known as penetration; otherwise it is termed overshooting We find that in threedimensional turbulent compressible convection at the parameters studied, motions generally overshoot a significant fraction of the local pressure scale height but do not establish an adiabatic penetrative region, even at

Cross-field blob transport in tokamak scrape-off-layer plasmas

Abstract: Recent measurements show that nondiffusive, intermittent transport of particles can play a major role in the scrape-off-layer (SOL) of fusion experiments. A possible mechanism for fast convective plasma transport is related to the plasma filaments or “blobs” observed in the SOL with fast cameras and probes. In this paper, physical arguments suggesting the importance of blob transport [S. I. Krasheninnikov, Phys. Lett. A 283, 368 (2001)] have been extended by calculations using a three-field fluid model, treating the blobs as coherent propagating structures. The properties of density, temperature and vorticity blobs, and methods of averaging over ensembles of blobs to get the average SOL profiles, are illustrated. The role of ionization of background neutrals in sustaining the density blob transport is also discussed. Many qualitative features of the experiments, such as relatively flat density profiles and transport coefficients increasing toward the wall, are shown to emerge naturally from the blob trans...

Estimates of heat flow in the deep mantle based on the power requirements for the geodynamo

Abstract: [1] Regeneration of the magnetic field by convection in the core places demands on heat flow into the base of the mantle. If the heat flow is too low, thermal convection is shut off and the rate of generation of compositional buoyancy by the solidification of the core becomes too low to sustain the geodynamo. Conversely, a large heat flow causes rapid growth of the inner core, so that convection prior to the appearance of the inner core must be sustained by thermal buoyancy alone. The attendant requirements on primordial heat become more severe as the age of the inner core decreases. We show that estimates of the present-day heat flow satisfy the power requirements for the geodynamo. However, the resulting thermal history is incompatible with estimates of mantle temperatures prior to 3 Ga. This discrepancy can be resolved by accumulating radioactive isotopes in D″ or adding heat sources to the core.

Convective quasi-equilibrium in midlatitude continental environment and its effect on convective parameterization

Abstract: [1] The quasi-equilibrium assumption proposed by Arakawa and Schubert assumes that convection is controlled by the large-scale forcing in a statistical sense, in such a way that the stabilization of the atmosphere by convection is in quasi-equilibrium with the destabilization by the large-scale forcing. The assumption was developed largely based on observations in the tropical maritime environment and has not been evaluated in midlatitudes. This study examines the quasi-equilibrium assumption in midlatitude continental convection environment using summertime observations from the Southern Great Plains of the United States. Two complementary approaches are taken for this purpose. The first one compares the net time rate of change of convective available potential energy to that due to the large-scale forcing. The second one examines the contributions to the net change of CAPE from the boundary layer air and the free tropospheric air above. Results from both the approaches indicate that the quasi-equilibrium assumption is not well suited for midlatitude continental convection. It is shown that the net change of CAPE is comparable to and largely comes from that due to thermodynamic changes of the boundary layer air, while the contribution from the free troposphere above the boundary layer is negligible. The analysis also shows that the role of convective inhibition to suppress convection is the most pronounced when the large-scale forcing in the free troposphere is weak. On the basis of these and other observations, a modification to the quasi-equilibrium assumption is proposed. It assumes that convective and large-scale processes in the free troposphere above the boundary layer are in balance, so that contribution from the free troposphere to changes in CAPE is negligible. This assumption is then tested using the single column model of the NCAR CCM3 by modifying the closure in the CCM3 convection scheme. Such a modification significantly improves the single column model simulation. The applicability of this new quasi-equilibrium assumption to tropical convection environment is also discussed.

Bubble Behavior and Nucleate Boiling Heat Transfer in Saturated FC-72 Spray Cooling

Abstract: Bubble behavior during saturated FC-72 spray cooling was experimentally investigated. A heater previously used for pool boiling was used to allow direct comparison. The results are analyzed to reveal the interaction between bubbles and impinging droplets. The following are presented: (1) the importance of secondary nuclei entrained by impingement droplets, (2) the role of impinging droplets on bubble parameters such as growth, diameter at puncture, lifetime, life cycle and bubble number density, and (3) the relative contribution of nucleation, especially that of secondary nuclei, to the heat transfer. It is concluded that increasing the droplet flux increases the number of secondary nuclei helps to lower surface temperature for a given heat flux, increases the overall heat transfer coefficient, and increases heat transfer due to both nucleate boiling and enhanced convection. Increasing the droplet flux also shortens the bubble growth time (i.e., resulting in earlier bubble removal) and life cycle. However, increasing the droplet flux (and, therefore, secondary nucleation) for each of the three heat flux values does not affect the percentage of either nucleate or convection heat transfer. This suggests that both the nucleate and convection heat transfer are enhanced, as a result of increased secondary nuclei and turbulent mixing due to the impinging droplets.

Entropy Budget of an Atmosphere in Radiative–Convective Equilibrium. Part I: Maximum Work and Frictional Dissipation

Abstract: The entropy budget of an atmosphere in radiative–convective equilibrium is analyzed here. The differential heating of the atmosphere, resulting from surface heat fluxes and tropospheric radiative cooling, corresponds to a net entropy sink. In statistical equilibrium, this entropy sink is balanced by the entropy production due to various irreversible processes such as frictional dissipation, diffusion of heat, diffusion of water vapor, and irreversible phase changes. Determining the relative contribution of each individual irreversible process to the entropy budget can provide important information on the behavior of convection. The entropy budget of numerical simulations with a cloud ensemble model is discussed. In these simulations, it is found that the dominant irreversible entropy source is associated with irreversible phase changes and diffusion of water vapor. In addition, a large fraction of the frictional dissipation results from falling precipitation, and turbulent dissipation accounts fo...

New grids of ATLAS9 atmospheres I: Influence of convection treatments on model structure and on observable quantities

Abstract: Received ; accepted Abstract. We present several new sets of grids of model stellar atmospheres computed with modified versions of the ATLAS9 code. Each individual set consists of several grids of models with different metallicities ranging from (M/H) = 2.0 to +1.0 dex. The grids range from 4000 to 10000 K in Teff and from 2.0 to 5.0 dex in log g. The individual sets differ from each other and from previous ones essentially in the physics used for the treatment of the convective energy transport, in the higher vertical resolution of the atmospheres and in a finer grid in the (Teff, log g) plane. These improvements enable the computation of derivatives of color indices accurate enough for pulsation mode identification. In addition, we show that the chosen vertical resolution is necessary and sufficient for the purpose of stellar interior modelling.To explain the physical differences between the model grids we provide a description of the currently available modifications of ATLAS9 according to their treatment of convection. Our critical analysis of the dependence of the atmospheric structure and observable quantities on convection treatment, vertical resolution and metallicity reveals that spectroscopic and photometric observations are best represented when using an inefficient convection treatment. This conclusion holds whatever convection formulation investigated here is used, i.e. MLT(� = 0.5), CM and CGM are equivalent. We also find that changing the convection treatment can lead to a change in the effective temperature estimated from Stromgren color indices from 200 to 400 K.

Bulk Heating and Slender Magnetic Loops in the Solar Corona

Abstract: The heating of the solar corona and the puzzle of the slender high reaching magnetic loops seen in observations from the Transition Region and Coronal Explorer (TRACE) has been investigated through three-dimensional numerical simulations and found to be caused by the well-observed plasma flows in the photosphere displacing the footpoints of magnetic loops in a nearly potential configuration. It is found that even the small convective displacements cause magnetic dissipation sufficient to heat the corona to temperatures of the order of a million K. The heating is intermittent in both space and time—at any one height and time it spans several orders of magnitude, and localized heating causes transonic flows along field lines, which explains the observed nonhydrostatic stratification of loops that are bright in emission measure.

Heat Transfer in Single and Multiphase Systems

Abstract: INTRODUCTION Vector and Tensor Notations Fundamental Concepts and Definitions Eulerian and Lagrangian Descriptions Properties of a System Conductive Heat Transfer Convective Heat Transfer Radiation Heat Transfer Phase Change Heat Transfer Conservation of Energy Problems CONDUCTION HEAT TRANSFER Introduction One-Dimensional Heat Conduction Thermal and Contact Resistances Fins and Extended Surfaces Multidimensional Heat Conduction Graphical Solution Methods Analytical Methods Transient Heat Conduction Combined Transient and Spatial Effects References Problems CONVECTIVE HEAT TRANSFER Introduction Convection Governing Equations Velocity and Thermal Boundary Layers External Forced Convection Internal Forced Convection Free Convection Second Law of Thermodynamics Turbulence Modelling References Problems RADIATIVE HEAT TRANSFER Introduction Fundamental Processes and Equations Radiation Exchange Between Surfaces Thermal Radiation in Enclosures with Diffuse Gray Surfaces Solar Energy References Problems PHASE CHANGE HEAT TRANSFER Introduction Processes of Phase Change Mixture and Two-Fluid Formulations Interface Tracking References Problems GAS (VAPOR) - LIQUID SYSTEMS Introduction Boiling Heat Transfer Condensation Heat Transfer Devices with Vapor - Liquid Phase Change References Problems GAS - SOLID (PARTICLE) SYSTEMS Introduction Classification of Gas - Solid Flows Dynamics of Gas - Solid Flows Fluidized Beds References Problems LIQUID - SOLID SYSTEMS Introduction One-Dimensional Solidification and Melting Phase Change with Convection Phase Change with Coupled Heat and Mass Transfer Problems in Other Geometries Multi-Dimensional Solidification and Melting Dynamics of Liquid - Solid Flows Applications References Problems GAS -LIQUID - SOLID SYSTEMS Introduction Droplet Flows with Phase Change Gas Flows with Solidification and Melting Chemically Reacting Systems Multiphase Byproducts of Reacting Flows References Problems HEAT EXCHANGERS Introduction Tubular Heat Exchangers Cross-Flow and Shell-and-Tube Heat Exchangers Effectiveness - NTU Method of Analysis Condensers and Evaporators References Problems COMPUTATIONAL HEAT TRANSFER Finite Difference Methods Weighted Residual Methods Finite Element Method Hybrid Methods Numerical Methods for Other Applications Accuracy and Efficiency Improvements References Problems APPENDICES INDEX

Horizontal convection is non-turbulent

Abstract: Consider the problem of horizontal convection: a Boussinesq fluid, forced by applying a non-uniform temperature at its top surface, with all other boundaries insulating. We prove that if the viscosity, ν, and thermal diffusivity, κ, are lowered to zero, with σ ≡ ν/κ fixed, then the energy dissipation per unit mass, κ, also vanishes in this limit. Numerical solutions of the two-dimensional case show that despite this anti-turbulence theorem, horizontal convection exhibits a transition to eddying flow, provided that the Rayleigh number is sufficiently high, or the Prandtl number σ sufficiently small. We speculate that horizontal convection is an example of a flow with a large number of active modes which is nonetheless not ‘truly turbulent’ because e→0 in the inviscid limit.

Global hybrid simulation of the Kelvin-Helmholtz instability at the Venus ionopause

Abstract: [1] The Kelvin–Helmholtz (K-H) instability at the Venus ionopause is investigated using a two-dimensional global hybrid (particle ions, massless fluid electrons) model for the case where the interplanetary field is oriented transverse to the flow. In order to self-consistently study the kinetic processes at the Venus ionopause, we calculate the entire Venus ionopause–solar wind interaction region kinetically, including the ionosphere, ionopause transition layer, magnetosheath, and solar wind regions, by applying boundary-fitted coordinates to the particle-in-cell code. Calculations are done for the unmagnetized ionospheric condition. It is found that the distribution of ionopause surface waves generated by the K-H instability exhibits a clear asymmetry between hemispheres of upward and downward solar wind motional electric fields. In the hemisphere where the motional electric field points away from the ionosphere, our two-dimensional model observes the development of the instability from the subsolar location, where the Venus ionopause has been thought to be stable due to small velocity shear and stabilizing effects such as gravity stabilization. Ionospheric filaments (streamers) are highly elongated in this hemisphere, and perturbations on the scale of the planetary radius are observed at the flank of the ionotail. In the opposite hemisphere, the instability develops only in a limited region between solar zenith angles (SZA) of ∼40° and 90°, and the surface of the ionotail appears rather smooth except for some special cases. The wavelength of the dominant mode is very long (2000–3000 km) in this hemisphere due to the finite Larmor radius (FLR) stabilizing effect. We show that the process operating at the ionopause is not a localized one but is important for the dynamics of the ionosphere and other regions. The asymmetrical momentum transport across the ionopause yields an asymmetrical convection pattern of the ionosphere. Our model also shows the dynamic nature of the interaction. The dynamic ion removal process associated with the K-H instability is found to play a significant role in the ion escape from the planet (O+ removal rate of approximately several times 1025 particles per second).