Другие журналы

. A B C D E F G H I J K L M N O P R S T U V W Y Z К М С Т

Popov


Engineering Bulletin # 10, October 2016
УДК: 62-522
Wave Processes Control in Hydraulic Systems
Engineering Education # 10, October 2016
DOI: 10.7463/1016.0847697
pp. 39-55
Optimization of an electrohydraulic actuator for a servo drive with throttle control
Engineering Education # 12, December 2013
DOI: 10.7463/1213.0637872
The paper presents a problem-solving procedure for selecting parameters of an electrohydraulic actuator in order to reduce response time and hydraulic power consumption. To perform such optimization design variables of an electrohydraulic servo drive were selected; objectives were proposed to estimate design alternatives. An example of two-criterion optimization of a servo drive with throttle control was presented. These criteria were control flow and response time. Multi-objective modification of a genetic algorithm was used to obtain a Pareto front approximation. The concept described in this paper is based on generalization of optimization methods for the electrohydraulic servo actuator known from literature references and includes new proposals on the algorithm structure
Optimization of power subsystem of electrohydraulic servo drive with throttling governing
Engineering Education # 11, November 2013
DOI: 10.7463/1113.0623966
This paper describes optimization of the power subsystem of an electrohydraulic servo drive with throttling governing. The electrohydraulic servo drive was considered together with an electrohydraulic power amplifier replaced by a proportional link. Variable parameters were selected and objective functions for design alternatives were proposed in order to optimize the electrohydraulic servo drive. An example of two-criterion optimization of the power subsystem was considered in this paper. These criteria were nearness of phase-response characteristic to the axis of abscissae and the mass to power ratio. Multi-criterion modification of genetic algorithm was used to obtain the Pareto front. The described concept is based on generalization of optimization methods for the  electrohydraulic servo drive known from literature references and includes new proposals on the structure of the optimization algorithm.
Selection of optimum parameters for the hydraulic drive of a fan of a vehicle’s engine cooling system
Engineering Education # 07, July 2013
DOI: 10.7463/0713.0590873
The authors consider a problem of choosing optimal parameters for a hydraulic drive with a discrete control output link by the example of a hydraulic fan of a heavy-duty vehicle’s engine cooling system. The objective function was selected in accordance with the efficiency criterion of the hydrostatic power drive. Limits of variable parameters’ values were set to reflect the work of the hydraulic drive in the specified system. Results of the application of genetic and modified genetic algorithms for determining parameters of the hydraulic drive were described in this article. The obtained results were compared with the results based on the LPτ- search of hydraulic parameters, optimal by two criteria. Academic novelty of this article consists in consideration of different approaches to the problem of interactive design of technical systems with discrete controls which is composed of commercially available standard hydraulic units.
Concept of optimization of an electrohydraulic servo drive with throttle regulation
Engineering Education # 06, June 2013
DOI: 10.7463/0613.0569281
This paper presents a technique of sequential optimization of an electrohydraulic servo drive. The electrohydraulic servo drive was considered as a set of subsystems of level 1 (Lv. 1) and level 2 (Lv. 2). At level 1 the electrohydraulic servo drive was considered together with an electrohydraulic servo valve replaced with a proportional link. A two-stage nozzle-flapper servo valve with mechanical feedback from the spool to the flap was selected at level 2. Objective functions were proposed to estimate project variants of each subsystem. Optimization by investigation of parameter space using the method based on the LP-sequences or genetic algorithms were presumed to be suitable. The concept described in the article is based on generalization of methods of electrohydraulic servo actuator optimization, which are known in the literature, and includes new proposals on the structure of the optimization algorithm. 
Automatic pressure regulation at the input of the main line pump during emergency cutout of an electric motor
Engineering Education # 01, January 2013
DOI: 10.7463/0113.0518041
This article describes a method of mathematical modeling of systems with centrifugal pumps. A structure chart directed at interactive solution of an optimal control problem of controlling pumping units was created with the use of this mathematical model. In this article, along with the results of calculations, the authors provide an example of an emergency cutout of a pumping module subject to the inertia of the pumping unit rotor, rotating frequency of its spindle, the pump’s head-capacity curve and parameters which determine hydraulic wave processes in the pipelines connected with the pump. Controlled parameters in this case are the pump module’s shaft speed and pressure generated by irregular fluid motion on intake side of the pump. Transition processes were determined for these parameters in case of an emergency cutout of the main line pump’s electric drive. Schematic diagram of the proposed mathematical model for investigation of centrifugal pump’s emergency modes was published for the first time
Balancing hydrodynamic forces by shaping valve’s surface
Engineering Education # 11, November 2012
DOI: 10.7463/1112.0491497
A method of reducing power required for electromechanical converter by balancing hydrodynamic forces acting on the control valve was considered. To calculate these forces, the finite element method was used; it allows one to determine the shape of the valve’s surface, which provides minimal values of hydrodynamic forces. In addition, graphs were plotted in order to compare the values of hydrodynamic forces obtained with the finite element method for unshaped and shaped spools, for two types of spool-type valve (supply of liquid in the center and along the edges of the valve). Using the finite element method, the distribution of pressure over the surface of the valve having the diameter of 6 mm, in the gap and the cavity of the spool-type valve was performed. Results of computer shaping of the valve and investigation of the influence of manufacturing precision of the valve on balancing hydrodynamic forces are given in the article.
Computer study and calculation of hydrodynamic loads on the valve
Engineering Education # 10, October 2012
DOI: 10.7463/1112.0491484
The authors provide results of computer studies and calculations of hydrodynamic forces influencing the valve. With the use of FEM they determined pressure distribution on the surface of the valve which had the diameter of 6 mm in cavities 1 and 2. Moreover, the authors obtained distribution of axial hydrodynamic forces influencing the valve in the cavity 1 and cavity 2 with the valve shift to a maximum value of 0.6 mm; and they build graphs to compare the values of the hydrodynamic forces calculated by FEM and analytical method. The calculation results are confirmed by experimental data previously published by other authors. With the help of the developed methods the authors determined the effect of changing the temperature of the working fluid (oil) in the range from -40 ° C to +50 ° C of hydrodynamic forces.
77-30569/274914 Hydrodynamic loading of the rotors of centrifugal pumps by step response processes
Engineering Education # 12, December 2011
Loads on centrifugal pump details change when disbursements of liquid in the “pump – pipes” system change. Mathematical model of the system and calculations indicate possible increase of hydrodynamics forces in the double-entry pump. The results can be used in pump bearings design.
About indefiniteness of own frequency of a drosselling hydraulic actuator.
Engineering Education # 07, July 2011
The wave model a current of liquid in a hydraulic actuator is considered. It is shown that own frequency of a drosselling hydraulic actuator can decrease in 1,41 times at the identical weight led to a target link. As a result of numerical experiments influence of nonlinearity of a dynamic characteristic on self-oscillatory processes arising in a hydraulic actuator is defined. Results of numerical experiments have been compared with results of tests of the hydro-mechanical monitor drive applied in laboratory installation of chair E-10 "The hydromechanics, the hydrocars and Hydro-pneumatic Systems" MSTU named after N. E. Bauman. Values of frequencies of self-oscillations received at tests of the laboratory sample of a hydromechanical actuator and registered at numerical experiments are almost equal and differ from calculated on linear mathematical model in 1,41 times. Thus, it is possible to conclude that the decrease in own frequency of self-oscillations of a hydromechanical drive found out at mathematical modeling represents the facts.
 
SEARCH
 
elibrary crossref ulrichsweb neicon rusycon
Photos
 
Events
 
News



Authors
Press-releases
Library
Conferences
About Project
Rambler's Top100
Phone: +7 (915) 336-07-65 (строго: среда; пятница c 11-00 до 17-00)
  RSS
© 2003-2024 «Наука и образование»
Перепечатка материалов журнала без согласования с редакцией запрещена
 Phone: +7 (915) 336-07-65 (строго: среда; пятница c 11-00 до 17-00)