Engineered Estimate of the Design Parameters of a Built-up Jet-Forming Nozzle for Mobile Underwater Waterjet Cutting Systems

2021 ◽  
pp. 30-39
Author(s):  
A.A. Ilyukhina ◽  
V.I. Kolpakov ◽  
V.V. Veltishchev
Keyword(s):  
Mathematical Model ◽  
Low Power ◽  
Working Conditions ◽  
High Speed ◽  
Field Experiments ◽  
Jet Flow ◽  
Design Parameters ◽  
Structural Element ◽  
Waterjet Cutting ◽  
Output Characteristics

The adaptation of waterjet cutting technology to underwater working conditions will allow solving various tasks when performing underwater technological operations, including maintenance of man-made hazardous objects. The implementation of such technology under water is possible with the application of mobile installations having low power, which imposes certain restrictions on its use. A method for improving the efficiency of mobile installations implementing underwater waterjet cutting is proposed. The method is based on the use of a built-up jet-forming path consisting of a diamond nozzle, an additional transition tube and a standard focusing tube. The structural externality of the diamond nozzle is given. A physical and mathematical model of the process of forming a high-speed jet which implements the technology of underwater hydro- or waterjet cutting, when the flow of a suspension under pressure passes through the jet-forming path of the proposed design, is described. Using calculations based on the developed model and results of field experiments, the effect of the structural element parameters of the built-up jet-forming path on the output characteristics of the formed jet flow is determined. The possibilities of applying such a design for controlling the output characteristics of the formed high-speed jet are assessed and the practicability of its use is indicated.

scholarly journals Development of the computer model of the plasma installation

2021 ◽  
Vol 2064 (1) ◽  
pp. 012044
Author(s):  
R A Okulov ◽  
E V Popov ◽  
B R Gelchinsky ◽  
A A Rempel
Keyword(s):  
Mathematical Model ◽  
Computer Model ◽  
Field Experiments ◽  
Characteristic Point ◽  
Plasma Jet ◽  
Jet Flow ◽  
Technological Equipment ◽  
Full Scale Experiment ◽  
Real Process ◽  
Scale Experiment

Abstract Mathematical model of a plasma installation for the production of metal powder and coating has been developed. The problem of creating an objective mathematical model of the plasma jet flow is solved, which adequately describes the real process and allows predicting the parameters of the plasma jet. The value of the temperature of the plasma jet at a characteristic point located on its axis is investigated. The computer model was verified by carrying out a full-scale experiment. Comparative analysis of the results of numerical and field experiments showed satisfactory convergence. It is shown that the temperature of the plasma jet flow obeys the normal Gaussian distribution. The research results can be used to improve processes and technological equipment.

A Method for Measuring the Dynamic Behaviour of the Rome-Florence High-Speed Track Switch Manoeuvring System

1992 ◽  
Vol 206 (2) ◽  
pp. 107-116 ◽  
Author(s):  
A Bracciali ◽  
M Biagiotti
Keyword(s):  
Mathematical Model ◽  
Working Conditions ◽  
High Speed ◽  
Test Bench ◽  
Dynamic Behaviour ◽  
Dynamic Loads ◽  
Test Procedures ◽  
Connection System ◽  
High Speed Trains ◽  
Physical Tests

A mathematical model of the dynamic loads induced at a switch machine and at the rails by the passing of a train was formulated and validated by physical tests. Attention was focused specifically on the switch machine itself and therefore the data gathered refers strictly to the attachment elements of the switch machine to the track and locally the track in the area of attachment. The research is part of a series of projects that aim to establish the factors that must be considered during the design of a switch machine. An accurate mathematical model of the connection elements between the track and the switch machine is helpful, especially in this period of widespread adoption of high-speed trains and the new working conditions that this imposes, in order to ascertain the characteristics of the accelerations transmitted to the switch machine and, as a consequence, to design the connection system of the machine to the track, based on these criteria. The data acquired can also be used for the construction of a realistic test bench to further improve test procedures. The pursuit of this project is a fundamental step in understanding the factors involved in the design of a switch machine.

scholarly journals Input shaping control of a flexible cantilever beam excited by a moving hub

2020 ◽  
Vol 3 (2) ◽  
pp. First
Author(s):  
Quoc Chi Nguyen ◽  
Nguyen Tri Giang Vu ◽  
Phuong Tung Pham
Keyword(s):  
Mathematical Model ◽  
Differential Equations ◽  
Ordinary Differential Equations ◽  
Cantilever Beam ◽  
High Speed ◽  
Beam Theory ◽  
Flexible Beam ◽  
Structural Element ◽  
Unknown Parameters ◽  
The Mathematical Model

Introduction: A cantilever beam is a well-known structural element in engineering, which is only fixed at one end. This structure can be used to describe a manipulator, whose stiffness is large to ensure rigidity and stability of the system. A flexible cantilever beam provides a light-weight structure and high cost efficiency but generates vibration under high-speed positioning. In this paper, we aim to control the vibratory behavior of a flexible cantilever beam attached to a moving hub. Method: The mathematical model of the flexible beam is described by partial differential equations (PDEs) using Euler-Bernoulli beam theory. Then, The PDE model is approximated by using the Galerkin method, which is resulted in a set of ordinary differential equations (ODEs). Experiment is used to determine unknown parameters of the system to complete the model. The ODE model enables the control design of three input shapers: (i) Zero-Vibration (ZV), (ii) Zero-Vibration-Derivative (ZVD), and (iii) Zero-Vibration-Derivative-Derivative (ZVDD), which are employed to drive the flexible beam to the desired position and to reduce vibrations of the beam. Results and conclusion: The dynamic model is obtained in term of ordinary differential equations. Unknown parameters of the system are determined by experimental process. Various controllers are designed to eliminate the vibration of the beam. The simulation is applied to predict the dynamic response of the beam to verify the designed controllers numerically. Experiment shows the validity of the mathematical model through the consistency between the simulation and experimental data and the effectiveness of the controllers for the real system. These controllers show several advantages such as no need of extra equipment; the positioning controller is intact, which means it may be applied to many existing systems.

Mathematical modeling and numerical simulation for determining an optimized oil jet layout for spiral bevel gear lubrication

2020 ◽  
pp. 135065012094232 ◽  
Author(s):  
X Zhu ◽  
Y Dai ◽  
F Ma ◽  
B Ouyang
Keyword(s):  
Mathematical Model ◽  
High Speed ◽  
Bevel Gear ◽  
Design Parameters ◽  
Spiral Bevel Gear ◽  
Heavy Load ◽  
Jet Nozzle ◽  
Simulation Results ◽  
Spiral Bevel ◽  
Oil Jet

In aeroengine industry, the oil jet layout significantly influences lubrication of high-speed and heavy-load transmission gears, as there is only extremely limited meshing clearance for the oil stream jetting into and an inevitable blocking effect of rotating gears. A novel mathematical model for calculating the exact impingement depth of the lubrication oil jet on the spiral bevel gear surface has been established, and it contains comprehensive and detailed design parameters for the jet nozzle layout and meshing gears. Furthermore, under different jet layout parameters conditions, computational fluid dynamic numerical simulations for oil jet lubrication of an aeronautical spiral bevel gear pair were conducted and, then, the simulation results are compared with the impingement depths based on the mathematical model. The simulation results reveal that the oil volume fraction and oil pressure on the meshing area increase with the impingement depth, validating the effectiveness and reliability of the method using the impingement depth mathematical model for evaluating oil jet lubrication. Optimized oil jet layout parameters including the jet nozzle position, jet elevation angle, and jet azimuth angle have been determined and recommended, and they provide valuable theoretical design methods and technical guidance for oil jet lubrication optimization for various practical high-speed and heavy-load spiral bevel gears.

HIGH SPEED AND LOW POWER 4*4 ARRAY MULTIPLIER DESIGN

2019 ◽  
Vol 7 (1) ◽  
pp. 24
Author(s):  
N. SURESH ◽  
K. S. SHAJI ◽  
KISHORE REDDY M. CHAITANYA ◽  
◽  
◽  
...  
Keyword(s):  
Low Power ◽  
High Speed ◽  
Array Multiplier

The Development of a Physico-Mathematical Model for the Functioning of an Underwater Waterjet Cutting Machine

2020 ◽  
Vol 75 (2) ◽  
pp. 167-174
Author(s):  
A. A. Ilukhina ◽  
V. I. Kolpakov ◽  
V. V. Veltishchev ◽  
A. L. Galinovsky ◽  
A. V. Khakhalin
Keyword(s):  
Mathematical Model ◽  
Waterjet Cutting ◽  
Cutting Machine

Design and Implementation of an Efficient Parallel LFSR Architecture for Wireless Communication Systems

2019 ◽  
Vol 14 ◽  
Author(s):  
A. Suresh Babu ◽  
B. Anand
Keyword(s):  
Wireless Communication ◽  
Power Consumption ◽  
Low Power ◽  
Communication Systems ◽  
High Speed ◽  
Design Tool ◽  
Shift Register ◽  
Linear Feedback ◽  
Wireless Communication Systems ◽  
Coverage Area

: A Linear Feedback Shift Register (LFSR) considers a linear function typically an XOR operation of the previous state as an input to the current state. This paper describes in detail the recent Wireless Communication Systems (WCS) and techniques related to LFSR. Cryptographic methods and reconfigurable computing are two different applications used in the proposed shift register with improved speed and decreased power consumption. Comparing with the existing individual applications, the proposed shift register obtained >15 to <=45% of decreased power consumption with 30% of reduced coverage area. Hence this proposed low power high speed LFSR design suits for various low power high speed applications, for example wireless communication. The entire design architecture is simulated and verified in VHDL language. To synthesis a standard cell library of 0.7um CMOS is used. A custom design tool has been developed for measuring the power. From the results, it is obtained that the cryptographic efficiency is improved regarding time and complexity comparing with the existing algorithms. Hence, the proposed LFSR architecture can be used for any wireless applications due to parallel processing, multiple access and cryptographic methods.

Sign in / Sign up

Export Citation Format

Share Document