Exploring the Behavior of a Coherent Flow Field Produced by a Shrouding Laval Nozzle Structure

Simulations of the supersonic flow field inside and outside of the Laval nozzle with single hole and nine holes were carried out based on the computational fluid dynamics method. The effects of different standoff distance and particle diameter on impact velocity of Cu particle spraying from single hole and nine holes were investigated firstly. The results show that the particle velocity obtained with the nine holes nozzle is higher than that of the single hole nozzle under the same standoff distance, and the smaller the standoff distance, the higher the particle velocity may be obtained with the nine holes, and the higher particle velocity may be obtained with smaller particle diameter for particles with diameters of 1 ~ 15 μm. Furthermore the effects of different spraying pressure and temperature on particle velocity of Cu particle spraying from the nine holes nozzle were also studied. And the simulations indicate that the higher the spraying pressure and temperature may make the particle spraying with greater velocity.

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Numerical Simulation of Flow Field in Air-Jet Loom Main Nozzle

Autex Research Journal ◽

10.1515/aut-2018-0053 ◽

2019 ◽

Vol 19 (2) ◽

pp. 181-190

Author(s):

Shanshan He ◽

Yi Qian ◽

Wenliang Xue ◽

Longdi Cheng

Keyword(s):

Flow Field ◽

Negative Pressure ◽

Fluid Dynamic ◽

Air Drag ◽

Zone Length ◽

Air Jet ◽

Pressure Zone ◽

Nozzle Exit Velocity ◽

Air Jet Loom ◽

Nozzle Structure

Abstract To improve airflow injection capacity of the main nozzle and decrease backflow phenomenon, a new main nozzle structure with two throats is designed. Negative pressure value and negative pressure zone length are first proposed evaluating the strength of backflow phenomenon. Commercial computational fluid dynamic (CFD) code “Fluent” is performed to simulate the flow field inside and outside the main nozzle. Exit velocity increases about 10 m/s in new main nozzle. Airflow core length of the new main nozzle is 35% higher than that of commonly used main nozzle. Smaller negative pressure value and shorter negative pressure zone length mean a weaker backflow phenomenon in the new main nozzle. Bigger air drag force indicates stronger weft insertion ability in the new main nozzle.

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Launch Dynamic Characteristic of High Initial Velocity Grenade Launcher with Low Recoil

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.712-715.1455 ◽

2013 ◽

Vol 712-715 ◽

pp. 1455-1459

Author(s):

Jie Song ◽

Zhen Qiang Liao ◽

Ming Qiu

Keyword(s):

Initial Velocity ◽

Laval Nozzle ◽

Structure Design ◽

Simulation Software ◽

Spring Stiffness ◽

Design And Optimization ◽

Force Curves ◽

Motion Characteristics ◽

Automatic Mechanism ◽

Nozzle Structure

In order to reduce the recoil of High Initial Velocity Grenade Launcher (HIVGL) and obtain better firing precision, two reduction recoil structures - short recoil barrel structure and laval nozzle structure were used for HIVGL. Virtual prototype simulation model of HIVGL were established, the dynamics curves of automatic mechanism of HIVGL and human shoulder force curves were obtained when HIVGL was launched by dynamic simulation software - ADAMS. The motion characteristics of automatic mechanism and the variation regulation of the maximum shoulder force were analyzed with different combinations of HIVGL structures and nozzle chamber charge amount. The barrel floating spring stiffness, pre-pressure and the effect of barrel stroke on spring energy storage were also analyzed. As proved by the research results, the maximum recoil of HIVGL can be greatly reduced by introducing short recoil barrel structure and laval nozzle structure. This result provides a beneficial reference for structure design and optimization of HIVGL.

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Numerical simulation of flow field in a Laval nozzle based on one-dimensional Euler equation

Journal of Physics Conference Series ◽

10.1088/1742-6596/2012/1/012082 ◽

2021 ◽

Vol 2012 (1) ◽

pp. 012082

Author(s):

Han Cai ◽

Zirun Jiang

Keyword(s):

Numerical Simulation ◽

Flow Field ◽

Euler Equation ◽

Laval Nozzle ◽

One Dimensional

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An attempt to make a reliable assessment of the wet steam flow field in the de Laval nozzle

Heat and Mass Transfer ◽

10.1007/s00231-018-2313-7 ◽

2018 ◽

Vol 54 (9) ◽

pp. 2675-2681 ◽

Cited By ~ 5

Author(s):

Sławomir Dykas ◽

Mirosław Majkut ◽

Krystian Smołka ◽

Michał Strozik

Keyword(s):

Flow Field ◽

Laval Nozzle ◽

Steam Flow ◽

Wet Steam ◽

Reliable Assessment ◽

De Laval Nozzle ◽

Wet Steam Flow

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The Simulation Application for the Structure Design of the Etcher Nozzle

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.249-250.372 ◽

2012 ◽

Vol 249-250 ◽

pp. 372-377

Author(s):

Lin Sheng

Keyword(s):

Flow Field ◽

Plasma Etching ◽

Etching Rate ◽

Flow Simulation ◽

Structure Design ◽

Structure Parameters ◽

Simulation Technology ◽

Field Situation ◽

Nozzle Structure

With the higher and higher etching rate, the flow field situation of the plasma etching chamber became an important factor to design the etcher chamber structure. This paper studied the etcher nozzle structure in detail by using the flow simulation technology to analyze how to get uniform follow field on the surface of the etching wafer, and then this paper determined the structure parameters of the etcher nozzle.

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