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Results of an experimental study of blood properties are reported. To approach the boundary conditions of blood biophysics in a real flow, the viscoelastic measurements are carried out on surfaces coated with a 10-nm thick fibrous layer composed of extracellular matrix protein. For native whole blood, a plateau of the shear elastic modulus as a function of frequency is observed. It is concluded that a slow flow of blood plasma close to the vessel wall can generate a stationary plasma layer that contributes to the functional width of surface layers in blood vessels. The shear stress term calculated from the wall shear rate and blood viscosity becomes imprecise if it does not include the existence of this intermediate layer.

Using the previously established dependence of the excess viscosity on the internal energy density, a simple low-parameter equation was obtained to describe the krypton viscosity coefficient in a wide range of state parameters. It was shown that the proposed low-parameter equation for calculating the viscosity coefficient of liquid and gas allows for reliable extrapolation beyond the limits of the studied area.

The paper presents results of numerical simulation for development of localized disturbances emerging from a single source or double synchronous sources in a laminar boundary disturbances at the plate with the flow with the Mach number М = 2 (variants for different distances between sources). Simulation was performed using the FlowVision software complex at the parameters typical for T-324 wind tunnel (developed by ITAM SB RAS). The problem was studied in the range of linear development of disturbance. The study demonstrates that, depending on the distance between the sources, the generated disturbances might either enhance or decay in the downstream flow. The frequency-wavelet analysis of disturbance structure was performed. Two distanced local synchronous sources generate the disturbances with wavelet spectra: these spectra exhibits nodes and crests; their positions depend on the distances between two sources.

A technique is described and the results of an experimental study of the aerodynamic structure of a turbulent streamlining, velocity fluctuations and pressure fields on the surface of a single trench hole located on the wall of a flat rectangular channel are presented. The trench hole cross-section is a cylindrical segment with hemispheres at its edges. The measurements were carried out with a two-component laser-Doppler velocity meter at two angles of hole inclination relative to the flow direction φ=0 и 45°. The development of the flow in the direction transverse to the trench, as well as along its span, was studied. The fundamental difference between the velocity fields and their fluctuations in a trench located normally and at an angle to the flow is shown.

The paper deals with simulation study of aerodynamics and heat transfer for a case of a four-vortex furnace chamber designed for jet fire of brown coal from Eastern coal deposits. The combustion modeling is achieved by a set of linked submodels: they describe turbulent gas flow? Thermal and radiative heat transfer, the processes of degradation and burning of coal particles, NO_x generation. Simulation demonstrated that using of these types of brown coal in a specific-design furnace chamber creates a steady four-vortex flow structure that provides a uniform temperature field in the volume and admissible generation of NO_x .

Laser water jet processing is a new hybrid method developed on the basis of traditional laser processing technology. It combines high laser processing efficiency with the impact and cooling effects of water jets. Laser water jet processing can effectively process hard and brittle materials such as silicon. In-depth study of the processing technology has important practical significance. For this reason, the controlled variable method is used to study the influence of different processing parameters on groove depth. The research results show that with the increase of current and laser pulse width , the groove depth gradually increases; with the increase of laser repetition frequency and water jet velocity, the groove depth increases first and then decreases. The experiment of laser water jet processing silicon can provide guidance for processing other difficult-to-process materials in the future.

The flow-type microreactors, being designed for small-scale production of pharmaceutical substances, have a moderate volume and ensure steady synthesis for pharmaceutical production while using noninva-sive methods for mixing of ingredients. The paper describes experimental and simulation study of the efficiency for natural convection mechanisms for so-lutions mixing in a Y-type symmetric microreactor. The mixing zone is arranged for discovery of con-vection potential. We consider both variants of chemically inert and chemically active systems. A model reaction is represented by a rapid acid-base neutralization reaction. The theoretical model com-prises the 3D Navier-Stokes equation and the reac-tants transfer equation (written with account for non-linear diffusion). Experimental and numerical results have been compared. The dependency for the effec-tive mixing length on the instability type and sol-vents flow rates was found.

Industrial micron-size hexahydro-1,3,5-trinitro-1,3,5-triazine (m-RDX) has been widely used in RDX-based polymer-bonded explosives (PBX). However, m-RDX results in poor mechanical properties and adhesive properties of RDX-based PBX m-RDX-PBX). Nano-RDX (n-RDX) has a small particle size and a large specific surface area, which provides a larger contact area with the polymer system. Thus, the porosity and compressive properties of PBX are improved if n-RDX is used in RDX-based PBX (RDX-PBX). In this study, m-RDX and n-RDX are used in RDX-PBX. The microstructure, component content, compressive properties, sensitivity properties, and detonation properties of RDX-PBX are investigated. The results show that n-RDX can make RDX-PBX more compact than m-RDX. The strain of n-RDX-based PBX (n-RDX-PBX) is increased by 39.7 % as compared to that of m-RDX-PBX. Meanwhile, the content of each component in n-RDX-PBX is consistent with that of the formula. The sensitivity of n-RDX-PBX is lower as compared to that of m-RDX-PBX, whereas the detonation velocity, detonation pressure, and detonation heat of n-RDX-PBX are equivalent to those of m-RDX-PBX.

Explosives are often exposed to war environments at different temperatures. The shock initiation characteristics of explosives are related to their properties and the ambient temperature in which they are located. In the present work, the parameters of the Ignition and Growth model of the LX-04 explosive at different temperatures are determined, based on the shock initiation experiments at different temperatures. Furthermore, the impact sensitivity simulation of LX-04 at initial temperatures of 25, 60, 100, 150, and 170 °C is carried out, and the critical impact velocity at these initial temperatures is found to be 325, 280, 233, 201, and 194 m/s, respectively. Based on the present simulation data, a new model for the relationship between the critical impact velocity and initial temperature is proposed. In addition, the initial temperature of the explosive has an important effect on the detonation performance: the higher the initial temperature, the higher the impact sensitivity of LX-04, and the higher the peak temperature of detonation.

Experimental data on the electrical resistance of aluminum under shock compression are analyzed. The electrical resistance of two types of aluminum foil located in dielectrics with different shock impedances is measured by the electrical contact method. The resultant dependences of the electrical resistance of aluminum on the shock wave pressure are monotonically increasing functions of pressure. However, the dependence of the specific electrical resistance of aluminum on the shock wave pressure can be monotonic (foil in Plexiglas) or nonmonotonic (foil in fluoroplastic). In the latter cased, the specific electrical resistance first slightly decreases with an increase in pressure and then increases. This behavior can be explained by the competing effects of compression and temperature heating on the specific electrical resistance. Due to shock compression of metal foil in the dielectric with a smaller shock impedance (Plexiglas), the measured electrical resistance is greater than that in the dielectric with a greater shock impedance (fluoroplastic). This result is caused by the greater temperature heating of metal foil in Plexiglas. The reasons for the qualitative difference in the behavior of the specific electrical resistance of metal under static and dynamic compression are discussed.