Gyro-average method for global gyrokinetic particle simulation in realistic tokamak geometry

Gyro-average is a crucial operation to capture the essential finite Larmor radius effect (FLR) in gyrokinetic simulation. In order to simulate strongly shaped plasmas, an innovative multi-point average method based on non-orthogonal coordinates has been developed to improve the accuracy of the original multi-point average method in gyrokinetic particle simulation. This new gyro-average method has been implemented in the gyrokinetic toroidal code (GTC). Benchmarks have been carried out to prove the accuracy of this new method. In the limit of concircular tokamak, ion temperature gradient (ITG) instability is accurately recovered for this new method and consistency is achieved. The new gyro-average method is also used to solve the gyrokinetic Poisson equation, and its correctness has been confirmed in the long wavelength limit for realistic shaped plasmas. The improved GTC code with the new gyro-average method has been used to investigate the ITG instability with EAST magnetic geometry. The simulation results show that the correction induced by this new method in the linear growth rate is more significant for short wavelength modes where the finite Larmor radius (FLR) effect becomes important. Due to its simplicity and accuracy, this new gyro-average method can find broader applications in simulating the shaped plasmas in realistic tokamaks.

Diffractive Sensor Elements for Registration of Long-Term Instability at Writing of Computer-Generated Holograms

The research and development of methods using of the specialized diffractive microstructure sensors embedded in the pattern of computer-generated holograms (CGH) manufactured on circular and X-Y laser writing systems is discussed. These microstructures consist of two parts: one of which is written before the CGH in the field of future hologram and the second one is written during the long-term writing of the CGH. The shift between the first and second part of the microstructure is the trace of the writing errors and allows one to determine and calculate the error of CGH fabrication along both orthogonal coordinates. The developed method is based on the principle of diffraction-based overlay with 1D and 2D built-in diffractive microstructure-sensors. Mathematical modeling and results of experimental test writings of such diffractive microstructure sensors are described. The efficiency of using these types of build-in sensors for the writing errors estimation for CGHs is demonstrated.

An analysis of annular plate in curvilinear non-orthogonal coordinates with the help of equations of a shell theory

The complete system of equations of a linear theory of thin shells in curvilinear non-orthogonal coordinates proposed in the paper was taken as the basis of the investigation. Earlier, this system was used for static analysis of a long developable helicoid. In the article, this system is applied for the determination of stress-strain state of annular and circular plates under action of the external axisymmetric uniform load acting both in the plane of the plate and out-of-their plane. Presented results for annular plate given in the non-orthogonal coordinates ex-pand a number of problems that can be solved analytically. They can be used as the first terms of series of expansion of displacements of degrees of the small parameter if a small parameter method is applied for examining a long tangential developable helicoid.

A NEW CONTRIBUTION IN STOCHASTIC HYDRODYNAMIC LUBRICATION FOR ARBITRARY BIO-SURFACES

This paper shows a recent progress described in curvilinear, orthogonal coordinates of the method of estimation of stochastic bio-hydrodynamic lubrication parameters. Here are discussed real arbitrary movable, non-rotational living biological surfaces coated with phospholipid bi-layers and lubricated with biological liquids. Non-rotational, curvilinear cooperating biological surfaces take the place in various biological nods for example in sacra bone, femoral bone, knee cap, calf bone and hip joint, elbow joint, knee joint, jump joint. Moreover are assumed biological non-rotational friction nods between human skin and tightly sport dress lubricated with the sweat. The main focus of the paper was to demonstrate the influence of expected values variations and standard deviation of the human joint gap height on the hydrodynamic lubrication parameters occurring during the friction process. It is very important to notice that the random gap height variations imply on the apparent dynamic viscosity of biological fluid or synovial fluid.

On the promising areas for the development of tools and methods of improving the seismic safety of the territory of Dagestan

Обсуждаются перспективы использования новых аппаратурно-методических разработок Института геологии ДФИЦ РАН для повышения сейсмической безопасности территории Дагестана. По предварительным расчетам разработанная на их базе деформационная станция траншейного типа (ДСТТ) в десятки раз дешевле и эффективнее, чем известная подземная деформационная станция штольневого типа, что делает реальным создание в сейсмоопасных районах сети ДСТТ и существенно расширит круг контролируемых параметров земной коры. В число этих параметров войдут локальные объемные деформации вмещающей среды, локальные линейные деформации в трех ортогональных координатах, величина и направление максимальных сдвиговых деформаций, азимут простирания и угол падения плоскости максимальных сдвиговых деформаций, деформация кручения относительно вертикальной оси, сейсмодеформации по трем координатам в широком частотном и динамическом диапазоне, локальные наклоны по двум ортогональным азимутам, сейсмоакселерограммы по трем ортогональным координатам в динамическом диапазоне 100 децибел, среднемасштабные (100 м) линейные деформации по трем ортогональным координатам, градиенты среднемасштабных линейных деформаций, среднемасштабные наклоны земной коры в двух ортогональных азимутах, крупномасштабные горизонтальные движения земной коры, вертикальные движения земной коры неприливные изменения силы тяжести и ее производных, обусловленные тектоническими причинами, амплитуды и фазы приливных гармоник во временных изменениях деформаций, наклонов, силы тяжести и ее градиентов. Становится возможным регулярное разномасштабное картирование всех перечисленных параметров, что означает качественно новый уровень деформационного мониторинга земной коры. Показана целесообразность использования комплекса для организации сейсмопрогностических наблюдений на территории Дагестана. К другим областям возможного применения разработок относятся геологоразведка, прецизионные гравитационные эксперименты, деформационный мониторинг крупных инженерных сооружений, прецизионные станки и системы позиционирования, что придает их реализации дополнительную актуальность. Описанный комплексный мониторинг предложено дополнить режимным просвечиванием сейсмоактивных зон Восточного Кавказа с использованием тяжелых вибросейсмоисточников и сейсмическим микрорайонированием крупных населенных пунктов в соответствие с существующими нормами и правилами. The prospects of using new hardware and methodological developments of the Institute of Geology of the Dagestan Federal Research Center of RAS to improve the seismic safety of the territory of Dagestan are discussed. According to the preliminary calculations, the trench-type deformation station (TTDS) developed on their basis is ten times cheaper and more efficient than the well-known underground deformation tunnel-type station, which makes it possible to create a TTDS network in seismically hazardous areas and which expand significantly the range of controlled parameters of the earths crust. These parameters will include local volumetric deformations of the host medium, local linear deformations in three orthogonal coordinates, the magnitude and direction of maximum shear deformations, the strike azimuth and the angle of incidence of the plane of maximum shear deformations, torsional deformation relative to the vertical axis, seismic deformation along three coordinates in a wide frequency and dynamic range, local slopes along two orthogonal azimuths, seismic accelerograms along three orthogonal coordinates in dynamic range 100 decibels medium-scale (100 m) linear deformations along three orthogonal coordinates, gradients of medium-scale linear deformations, medium-scale crustal tilts in two orthogonal azimuths, large-scale horizontal earths crust movement, vertical movement of the earths crust non-tidal changes in gravity and its derivatives caused by the tectonic reasons, the amplitudes and phases of tidal harmonics in temporal variations of deformations, inclinations, gravity and its gradients. It becomes possible a regular multi-scale mapping of all these parameters, which means a qualitatively new level of deformation monitoring of the earths crust. The expediency of using the complex for the organization of seismic-prediction observations in the territory of Dagestan is shown. Other areas of potential development applications include geological exploration, precision gravity experiments, strain monitoring of large engineering structures, precision machines and positioning systems, which gives their implementation additional relevance. It is proposed to supplement the described complex monitoring with regime transmission of seismically active zones of the East Caucasus using heavy vibro-seismic sources and seismic microzonation of large settlements following the existing norms and rules