Investigation of the Influence of Laval Nozzle Throat Width via Euler-based Flow Simulation

This paper proposes a hydraulic measurement model for measuring the Laval nozzle throat diameter size. Based on measurement principle of liquid pressure – flowrate, we can get the size of Laval nozzle throat diameter by measuring the fluid flowrate through hydraulic measurement model at the fixed pressure. With good viscosity-temperature performance, low temperature performance and oxidation stability, UCBO aviation hydraulic oil is selected as the measuring medium. In the hydraulic measurement model, the diameter of the mandrel which can be regarded as gauge will directly affect the sensitivity of diameter measurement. Therefore we need to optimize the design of the mandrel of the hydraulic model.

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The influence of Laval nozzle throat size on supersonic molecular beam injection

Journal of Modern Transportation ◽

10.1007/s40534-014-0041-3 ◽

2014 ◽

Vol 22 (2) ◽

pp. 118-121 ◽

Cited By ~ 1

Author(s):

Xinkui He ◽

Xianfu Feng ◽

Mingmin Zhong ◽

Fujun Gou ◽

Shuiquan Deng ◽

...

Keyword(s):

Molecular Beam ◽

Laval Nozzle ◽

Nozzle Throat ◽

Supersonic Molecular Beam ◽

Beam Injection

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An Experimental Study of Flows in Planar Nozzles

Journal of Basic Engineering ◽

10.1115/1.3425525 ◽

1972 ◽

Vol 94 (3) ◽

pp. 682-688 ◽

Cited By ~ 1

Author(s):

J. A. Owczarek ◽

D. O. Rockwell

Keyword(s):

Discharge Coefficient ◽

Reynolds Numbers ◽

Flow Speed ◽

Secondary Flows ◽

Nozzle Throat ◽

Circular Duct ◽

Throat Width ◽

Number Flow ◽

Side Walls ◽

Low Mach Number Flow

The paper describes an experimental investigation of the characteristics of low-Mach number flow of air from four planar nozzles. The nozzles had rectangular (rounded) inlets from a circular duct and aspect ratio of 3 at the exit. In general, two types of spiraling secondary flows were observed at nozzle exits. One type was observed in the vicinity of the midplane of the nozzles near the upper and lower walls, and the other type in the vicinity of the side walls in the corners. Experiments have shown that the secondary flows located in the vicinity of the midplane are produced by the contraction from the circular duct to the rectangular inlet, while the secondary flows located in the vicinity of the side walls are produced by the boundary layer migration toward the convex inner wall sections of the nozzles. The secondary flows have low total pressure associated with them. A comparison of discharge coefficient is made for the nozzles examined. The experiments were performed at the Reynolds numbers, based on the average flow speed at the nozzle exit and nozzle throat width, in the range of 3.4 × 103 to 2.5 × 104.

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Flow Simulation as a Support to Predict Shape of Plasma Beam Affected by the Nozzle Geometry

MATEC Web of Conferences ◽

10.1051/matecconf/202032802008 ◽

2020 ◽

Vol 328 ◽

pp. 02008

Author(s):

Miloslav Málek ◽

Miloš Mičian ◽

Augustín Sládek

Keyword(s):

Laval Nozzle ◽

Flow Simulation ◽

Simulation Software ◽

Nozzle Geometry ◽

Ansys Fluent ◽

Beam Shape ◽

Nozzle Orifice ◽

Flow Simulations ◽

Plasma Beam ◽

Made In

This paper deals with flow simulation of plasma beam shape affected by the different nozzle geometry. The flow simulations for different nozzles geometry were made in simulation software Ansys-Fluent. The evaluation of flow simulations was based on comparing shapes of the flow media out from the modified nozzle orifice against reference nozzle. There were investigated 8 different modification of nozzle orifice. Modified nozzle n. 7 (in the shape of a Laval nozzle) has achieved significant improvement from all simulated. There were observed 3 cores of plasma beam, which could help blow dross out from cutting gap. Investigated results serve for further research.

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Choking Phenomena in a Vortex Flow Passing a Laval Tube: An Analytical Treatment

Journal of Fluids Engineering ◽

10.1115/1.3089532 ◽

2009 ◽

Vol 131 (4) ◽

Cited By ~ 1

Author(s):

Theo Van Holten ◽

Monique Heiligers ◽

Annemie Jaeken

Keyword(s):

Numerical Simulation ◽

Vortex Flow ◽

Laval Nozzle ◽

Analytical Theory ◽

Axial Component ◽

Nozzle Throat ◽

Analytical Treatment ◽

Test Channel ◽

Flow Through ◽

Total Velocity

The behavior of a vortex flow through a Laval nozzle was studied in connection with the purification of natural gas. By creating a vortex and passing it through a Laval nozzle, the gas will be cooled, and water droplets will form and will be centrifuged out of the gas. This system is named the Condi-Cyclone. An analytical theory is developed to reveal the most important phenomena of the flow, to first order accuracy. Experiments have been performed with a prototype of the Condi-Cyclone. A Euler numerical simulation was performed, using the geometry of the test channel. This paper presents an analytical theory for a vortex flow through a Laval nozzle. It will demonstrate that when a vortex is present the total velocity reaches sonic conditions upstream of the nozzle throat, that the axial component of the velocity in the nozzle throat is equal to the local speed of sound and that the mass flow through the Laval nozzle decreases with increasing vortex strength. The predictions of the analytical theory have been compared with the results of the experiments and the Euler numerical simulation, and it can be concluded that the analytical theory describes the main characteristics of the flow very well.

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HLP Type Hydraulic Oil Analysis for Meso-Scale Hole Measurement

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.667.427 ◽

2015 ◽

Vol 667 ◽

pp. 427-432

Author(s):

Xiang Zhang ◽

Yang Hong ◽

Guang Lin Wang ◽

Dong Xiang Shao ◽

Li Sun

Keyword(s):

Flow Field ◽

Measurement Method ◽

Laval Nozzle ◽

Measuring Method ◽

Field Analysis ◽

Nozzle Throat ◽

Hydraulic Oil ◽

Flow Field Analysis ◽

Throat Diameter ◽

Meso Scale

HLP type hydraulic oil has wide application in aerospace field. The existing measurement method of Laval nozzle throat diameter efficiency is low, and has the potential to cut parts surface. Therefore, a non-contact throat diameter measuring method based on the hydraulic oil is proposed. Then the flow field is simulated, and measurement parameters are calculated. The flow field analysis results show that this method is suitable for measuring Laval nozzle throat diameter.

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DESIGN AND FABRICATION OF MICRONOZZLES

IIUM Engineering Journal ◽

10.31436/iiumej.v12i1.65 ◽

2011 ◽

Vol 12 (1) ◽

pp. 51-62 ◽

Cited By ~ 2

Author(s):

Kean How Cheah ◽

Jit Kai Chin

Keyword(s):

Structural Material ◽

Approximate Method ◽

Soft Lithography ◽

High Performance ◽

Simple Technique ◽

Nozzle Throat ◽

Promising Candidate ◽

Ion Etching ◽

Deep Reactive Ion Etching ◽

Throat Width

Micronozzle, a key component in micropropulsion system, has been designed and fabricated. Quasi 1D inviscid theory was used in designing a series of conical micronozzles of different expander half-angles (10Â°-50Â°). Aerospike micronozzle, a promising candidate to achieve high performance propulsion system, was designed with Angelino method (or Approximate method). Both micronozzles were fabricated using soft lithography, an inexpensive and relatively simple technique comparing to well-established deep reactive ion etching (DRIE) technique, with polydimethylsiloxane (PDMS) as structural material. Micronozzles with two different nozzle throat width, 53.5Âµm and 107Âµm, were fabricated for comparison. Microscopic inspections reveal 107Âµm is the more producible nozzle throat width with current equipments. The PDMS-based micronozzle can be used as cold gas microthruster system for micro- and nanosatellites.

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