EXCITATION OF NONLINEAR PRESSURE OSCILLATIONS IN LOW-PRESSURE FLUID FLOW USING A HIGH-PRESSURE HYDRODYNAMIC GENERATOR

The results of the study of the excitation process of nonlinear oscillations of finite amplitude pressure in a low-pressure (treated) fluid flow using a hydrodynamic oscillator of flow type, the working fluid of which has no direct contact with the fluid of the treated flow, are presented. It is shown that the oscillations from the hydrodynamic generator can be transmitted to the fluid flow through the interface (matching device) in the form of a disk with a certain acoustic resistance. It was found that resonant oscillations can be disturbed in the low-pressure flow processing chamber. The conditions of excitation of resonant oscillations in the processing chamber with a flowing liquid are found. Numerical values of the oscillation span and resonance frequencies are given.

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Fluid Flow Through a Class of Highly-Deformable Porous Media. Part I: Experiments With Air

Journal of Fluids Engineering ◽

10.1115/1.3240807 ◽

1981 ◽

Vol 103 (3) ◽

pp. 432-438 ◽

Cited By ~ 15

Author(s):

G. S. Beavers ◽

A. Hajji ◽

E. M. Sparrow

Keyword(s):

Porous Media ◽

Fluid Flow ◽

Analytical Model ◽

Mass Flow ◽

Applied Pressure ◽

Companion Paper ◽

Working Fluid ◽

Internal Stresses ◽

Deformable Porous Media ◽

Flow Through

This paper, together with a companion paper which follows, describes a many-faceted experimental investigation aimed at determining basic characteristics of fluid flow through deformable porous media. A major focus of the work is to establish the validity and the range of applicability of a simple analytical model for the fluid flow. The present paper describes experiments with a gas (air) as the working fluid, while the companion paper (Part II) deals with liquid-flow (i.e., water-flow) experiments. The experiments encompassed three distinct phases. In the first phase, the stress-deformation characteristics were measured (without fluid flow). In the second, flow-related material properties that are relevant to the analytical model (e.g., permeability, Forchheimer coefficient) were determined. The third phase consisted of measurements of mass flow rate as a function of applied pressure differential. The results of the first two phases were used as input to the analytical model, which yielded predictions of mass flow versus applied pressure. These predictions were shown to be in very good agreement with the experimental results, for those conditions where the model is applicable. Two unusual features of the participating deformable materials (polyurethane foams) were encountered, namely, a decrease of cross-sectional area with increasing compression and a slow relaxation of the internal stresses at a fixed compression.

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An experimental investigations of the single phase fluid flow through mini pipes with circular cross section

Scientific Bulletin of Naval Academy ◽

10.21279/1454-864x-20-i2-003 ◽

2020 ◽

Vol XXIII (2) ◽

pp. 25-31

Author(s):

Avram Elena Rita

Keyword(s):

Fluid Flow ◽

Cross Sections ◽

Circular Cross Section ◽

Experimental Results ◽

Working Fluid ◽

Total Hardness ◽

Experimental Investigations ◽

Turbulent Friction ◽

Pressure Drops ◽

Flow Through

The experimental investigation that has been conducted on the fluid flow in mini pipes with circular cross-sections are presented in this paper. The working fluid is water and its main physical-chemical analysis (pH, total hardness, electrical conductivity) were carried out. The liquid flow through mini pipes of 1, 2 and 3 mm diameter with simulated pressure drops from 1.01 to 61 bar is investigated and the experimental results are presented. The laminar and turbulent friction factor f at different pressure drop values, the transition from the laminar to turbulent flow, the effect of relative roughness, and the boundary-layer thickness, δ, are computed and studied. The experimental results are presented, discussed and analysed, according to the theoretical principles.

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Numerical analysis of heat transfer and fluid flow through the twisted square duct (TSD): Nanofluid as working fluid

Journal of Mechanical Science and Technology ◽

10.1007/s12206-019-1043-1 ◽

2019 ◽

Vol 33 (11) ◽

pp. 5507-5514 ◽

Cited By ~ 1

Author(s):

Shambhu Kumar Mahato ◽

Subhas Chandra Rana ◽

Rabindra Nath Barman ◽

Sohom Goswami

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Numerical Analysis ◽

Working Fluid ◽

Square Duct ◽

Flow Through

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Modeling the working media flow in shut-off valves with displacement of the regulating body perpendicular to the flow axis

Journal of Physics Conference Series ◽

10.1088/1742-6596/2057/1/012017 ◽

2021 ◽

Vol 2057 (1) ◽

pp. 012017

Author(s):

V V Soloveva ◽

A S Pugachuk ◽

A V Chernyschev

Keyword(s):

Fluid Flow ◽

Gas Flow ◽

Reynolds Numbers ◽

Working Fluid ◽

Flow Section ◽

Flow Parameters ◽

Wide Range ◽

Flow Part ◽

Flow Through ◽

Working Media

Abstract The mathematical model of the working fluid movement in the flow section of the wedge type two-disc parallel gate valve is developed. The simulation of the fluid flow through the valve cavity is carried out, as a result the flow parameters are obtained in a wide range of Reynolds numbers at the entrance to the calculated area. The dependence of the hydraulic resistance as a function of the Reynolds number for liquid and gas flow is calculated. The various positions of the shut-off body in the flow part of the valve are considered and the area of reduced pressures in which the effect of cavitation may occur during fluid flow is estimated.

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