On the Frame Properties of System of Exponents with Piecewise Continuous Phase

The paper considers a method for simulating the flight of a multistage rocket in Matlab using Simulink software for control and guidance. The model takes into account the anisotropy of the gravity of the Earth, changes in the pressure and density of the atmosphere, piecewise continuous change of the center of mass and the moment of inertia of the rocket during the flight. Also, the proposed model allows you to work out various targeting options using both onboard and ground‑based information tools, to load information from the ground‑based radar, with imitation of «non‑ideality» of incoming target designations as a result of changes in the accuracy of determining coordinates and speeds, as well as signal fluctuations. It is stipulated that the design is variable not only by the number of steps, but also by their types. The calculations are implemented in a matrix form, which allows parallel operations in each step of processing a multidimensional state vector of the simulated object.

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A model of the counter-current flow of the dispersed and the continuous phase. Monodispersed system

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19763696 ◽

1976 ◽

Vol 41 (12) ◽

pp. 3696-3708

Author(s):

J. Procházka ◽

V. Jiřičný ◽

H. Steidl

Keyword(s):

Current Flow ◽

Continuous Phase ◽

Counter Current Flow ◽

Counter Current

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Phase Inversion in Two-Phase Liquid Systems

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19921419 ◽

1992 ◽

Vol 57 (7) ◽

pp. 1419-1423

Author(s):

Jindřich Weiss

Keyword(s):

Interfacial Tension ◽

Phase Inversion ◽

Continuous Phase ◽

Considerable Effect ◽

Weak Dependence ◽

Dispersed Phase ◽

Two Phase ◽

Liquid Systems ◽

Phase Liquid

New data on critical holdups of dispersed phase were measured at which the phase inversion took place. The systems studied differed in the ratio of phase viscosities and interfacial tension. A weak dependence was found of critical holdups on the impeller revolutions and on the material contactor; on the contrary, a considerable effect of viscosity was found out as far as the viscosity of continuous phase exceeded that of dispersed phase.

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Modeling the Excess Velocity of Low-Viscous Taylor Droplets in Square Microchannels

Fluids ◽

10.3390/fluids4030162 ◽

2019 ◽

Vol 4 (3) ◽

pp. 162 ◽

Cited By ~ 2

Author(s):

Thorben Helmers ◽

Philip Kemper ◽

Jorg Thöming ◽

Ulrich Mießner

Keyword(s):

High Speed ◽

Process Intensification ◽

Continuous Phase ◽

Channel Cross Section ◽

Optimization Approach ◽

Mean Flow ◽

Bypass Flow ◽

Wall Film ◽

Proposed Model ◽

The Mean

Microscopic multiphase flows have gained broad interest due to their capability to transfer processes into new operational windows and achieving significant process intensification. However, the hydrodynamic behavior of Taylor droplets is not yet entirely understood. In this work, we introduce a model to determine the excess velocity of Taylor droplets in square microchannels. This velocity difference between the droplet and the total superficial velocity of the flow has a direct influence on the droplet residence time and is linked to the pressure drop. Since the droplet does not occupy the entire channel cross-section, it enables the continuous phase to bypass the droplet through the corners. A consideration of the continuity equation generally relates the excess velocity to the mean flow velocity. We base the quantification of the bypass flow on a correlation for the droplet cap deformation from its static shape. The cap deformation reveals the forces of the flowing liquids exerted onto the interface and allows estimating the local driving pressure gradient for the bypass flow. The characterizing parameters are identified as the bypass length, the wall film thickness, the viscosity ratio between both phases and the C a number. The proposed model is adapted with a stochastic, metaheuristic optimization approach based on genetic algorithms. In addition, our model was successfully verified with high-speed camera measurements and published empirical data.

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Effects of Blade Parameters on the Flow Field and Classification Performance of the Vertical Roller Mill via Numerical Investigations

Mathematical Problems in Engineering ◽

10.1155/2020/3290694 ◽

2020 ◽

Vol 2020 ◽

pp. 1-15

Author(s):

Chang Liu ◽

Zuobing Chen ◽

Weili Zhang ◽

Chenggang Yang ◽

Ya Mao ◽

...

Keyword(s):

Flow Field ◽

Pressure Difference ◽

Continuous Phase ◽

Classification Performance ◽

Field Analysis ◽

Discrete Phase Model ◽

Roller Mill ◽

Discrete Phase ◽

Vertical Roller ◽

Classification Efficiency

The vertical roller mill is an important crushing and grading screening device widely used in many industries. Its classification efficiency and the pressure difference determine the entire producing capacity and power consumption, respectively, which makes them the two key indicators describing the mill performance. Based on the DPM (Discrete Phase Model) and continuous phase coupling model, the flow field characteristics in the vertical roller mill including the velocity and pressure fields and the discrete phase distributions had been analyzed. The influence of blade parameters like the shape, number, and rotating speed on the flow field and classification performance had also been comprehensively explored. The numerical simulations showed that there are vortices in many zones in the mill and the blades are of great significance to the mill performance. The blade IV not only results in high classification efficiency but also reduces effectively the pressure difference in the separator and also the whole machine. The conclusions of the flow field analysis and the blade effects on the classification efficiency and the pressure difference could guide designing and optimizing the equipment structure and the milling process, which is of great importance to obtain better overall performance of the vertical roller mill.

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