scholarly journals PERFORMANCE OF HIGH-POWER VACUUM FISH PUMPING UNITS

Fisheries ◽  
2020 ◽  
Vol 2020 (4) ◽  
pp. 101-105
Author(s):  
Vladimir Naumov ◽  
Nikolay Velikanov ◽  
Anton Zemlyanov
Keyword(s):  
Differential Equations ◽  
Numerical Method ◽  
High Power ◽  
Vacuum Pump ◽  
Time Intervals ◽  
Pump Operation ◽  
Water Fish ◽  
Pumping Units ◽  
Water Ring

The article describes the features of modeling the stages of pumping a waterfish mixture using a water-ring vacuum pump. The dynamics of pressure changes in reservoir during pump operation for different time intervals is considered. Solutions of the corresponding differential equations are obtained using the numerical method. The calculated characteristics of the process of water-fish mixture pumping into the receiving container are presented.

STAGES OF VACUUM FISH-PUMP UNIT OPERATION

Fisheries ◽  
2020 ◽  
Vol 2020 (2) ◽  
pp. 108-112 ◽  
Author(s):  
Vladimir Naumov ◽  
Nikolay Velikanov
Keyword(s):  
Numerical Method ◽  
Vacuum Pump ◽  
Unit Operation ◽  
Working Capacity ◽  
Pump Unit ◽  
Time Intervals ◽  
Pump Operation ◽  
Water Fish ◽  
Pressure Changes ◽  
Water Ring

The article describes the features of modeling the stages of pumping a water- fish mixture using a water-ring vacuum pump. The dynamics of pressure changes in the working capacity during pump operation for different time intervals is considered. Solutions of the corresponding differential equations are obtained using the numerical method. The results of calculating the characteristics of the process of pumping the water- fish mixture into the receiving container are presented.

CHARACTERISTICS OF WATER RING COMPRESSOR MACHINES VACUUM FISH PUMPING UNITS

Fisheries ◽  
2021 ◽  
Vol 2021 (1) ◽  
pp. 94-98
Author(s):  
Vladimir Naumov ◽  
Nikolay Velikanov
Keyword(s):  
Experimental Data ◽  
Power Consumption ◽  
Least Squares Method ◽  
Vacuum Pump ◽  
Rotor Speed ◽  
Pump Mode ◽  
Working Chamber ◽  
Pumping Units ◽  
Water Ring ◽  
Empirical Constants

The operation of the Samson KS910 pump under various conditions is investigated. The values of empirical constants in mathematical dependencies for calculating pump characteristics were found using the least squares method based on published experimental data. The results of calculating the productivity and power consumption of the Samson KS910 in the vacuum pump mode depending on the pressure in the working chamber at different values of the rotor speed and pressure in the working chamber are presented.

Steady-state modelling method for matrix-reactance frequency converter with boost topology

2011 ◽  
Vol 60 (2) ◽  
pp. 137-148
Author(s):  
Igor Korotyeyev ◽  
Beata Zięba
Keyword(s):  
Fourier Series ◽  
Steady State ◽  
Differential Equations ◽  
Numerical Method ◽  
Frequency Converter ◽  
Double Fourier Series ◽  
Galerkin’S Method ◽  
Galerkin's Method ◽  
Modelling Method ◽  
Three Phase

Steady-state modelling method for matrix-reactance frequency converter with boost topologyThis paper presents a method intended for calculation of steady-state processes in AC/AC three-phase converters that are described by nonstationary periodical differential equations. The method is based on the extension of nonstationary differential equations and the use of Galerkin's method. The results of calculations are presented in the form of a double Fourier series. As an example, a three-phase matrix-reactance frequency converter (MRFC) with boost topology is considered and the results of computation are compared with a numerical method.

Caputo fractional differential equations with non-instantaneous impulses and strict stability by Lyapunov functions

Filomat ◽  
2017 ◽  
Vol 31 (16) ◽  
pp. 5217-5239 ◽  
Author(s):  
Ravi Agarwal ◽  
Snehana Hristova ◽  
Donal O’Regan
Keyword(s):  
Differential Equations ◽  
Fractional Differential Equations ◽  
Lyapunov Functions ◽  
Sufficient Conditions ◽  
Time Intervals ◽  
Dini Derivative ◽  
Comparison Results ◽  
Strict Stability ◽  
Caputo Fractional Differential Equations ◽  
Fractional Differential

In this paper the statement of initial value problems for fractional differential equations with noninstantaneous impulses is given. These equations are adequate models for phenomena that are characterized by impulsive actions starting at arbitrary fixed points and remaining active on finite time intervals. Strict stability properties of fractional differential equations with non-instantaneous impulses by the Lyapunov approach is studied. An appropriate definition (based on the Caputo fractional Dini derivative of a function) for the derivative of Lyapunov functions among the Caputo fractional differential equations with non-instantaneous impulses is presented. Comparison results using this definition and scalar fractional differential equations with non-instantaneous impulses are presented and sufficient conditions for strict stability and uniform strict stability are given. Examples are given to illustrate the theory.

An implicit multistep numerical method for real-time simulation of stiff systems

SIMULATION ◽  
2021 ◽  
pp. 003754972110216
Author(s):  
Zhang Lei ◽  
Li Jie ◽  
Wang Menglu ◽  
Liu Mengya
Keyword(s):  
Differential Equations ◽  
Numerical Method ◽  
Real Time ◽  
Physical System ◽  
Physical Models ◽  
Stiff Systems ◽  
Real Time Simulation ◽  
Stiff Ordinary Differential Equations ◽  
Root Finding ◽  
Time Simulation

Simulating a physical system in real-time is widely used in equipment design, test, and validation. Though an implicit multistep numerical method excels at solving physical models that are usually composed of stiff ordinary differential equations, it is not suitable for real-time simulation because of state discontinuity and massive iterations for root finding. Thus, a method based on the backward differential formula is presented. It divides the main fixed step of real-time simulation into limited minor steps according to computing cost and accuracy demand. By analyzing and testing its capability, this method shows advantage and efficiency in real-time simulation, especially when the system contains stiff equations. A simulation application will have more flexibility while using this method.

Sign in / Sign up

Export Citation Format

Share Document