НИЦ "Моринтех"

PROBABILITY FATIGUE CORROSION STRENGTH CRITERION OF THIN WALLED STRUCTURES

Arutyunyan R. A., Arutyunyan A. R.
State University of St. Petersburg
e-mail: Robert.Arutyunyan@paloma.spbu.ru
tel.: (812) 526-65-91
The kinetic equation tacking into account the important role of stress intensity factor in the process of fatigue corrosion crack propagation and the probability fatigue fracture model of thin walled structures are presented. The length of crack propagation and fatigue rupture curves according to the theoretical relations are constructed. As it is shown, they are in good agreement with the basic experimental results of the response of metallic materials and structures to the attack of corrosive media.
Key words: fatigue corrosion crack propagation, stress intensity factor, specimen with a crack, thin walled structures, probability fatigue fracture model.

MANAGEMENT AND DECISION MAKING AT SHIP STRENGTH OPERATION CONTROL ON THE BASIS OF MODERN CATASTROPHE THEORY

Burakovskiy E. P., Nechaev Y. I.
Burakovskiy P. E., Prokhnich V. P.
Kaliningrad state technical university
e-mail: e_burakovsky@mail.ru
tel.: 8-4012-36-43-38
An approach based on interpreting current situations with the use of onboard intellectual systems (IS) of providing sea going safety is discussed. This approach allows in uncertainty conditions to present physical picture of situation development and to construct its dynamic model on the basis of modern catastrophe theory. For the sake of example a situation of loosing strength in the rough waters is discussed.
Key words: non linear system, decision making, catastrophe theory.

COMPLEX ONTOLOGY AT KNOWLEDGE FORMALIZING OF INTELLECTUAL CONTROL SYSTEM OF OPERATIONAL VESSEL STRENGTH

Burakovskiy P. E., Nechaev Y. I.
Kaliningrad state technical university
e-mail: e_burakovsky@mail.ru
tel.: 8-4012-36-43-38
Problems of knowledge formalizing on the basis of complex ontology for extreme situations modeling in the intellectual system of vessel strength control are discussed. Special attention is paid for solving problem of describing subject matter in uncertainty conditions and insufficiency of initial information.
Key words: complex ontology, catastrophe theory, strength control.

CALCULATION OF EXTERNAL FORCES IN PLANE PROBLEMS OF THE INTERACTION OF ACOUSTIC SHOCK WAVES ON OBSTACLES WITH THE HELP OF THE DIFFRACTION INTEGRAL

Kadyrov S. G.,Grigoriev-Golubev V. V.
State Marine Technical University of St. Petersburg
tel.: (812) 757-19-11
e-mail: skadyrov@gmail.com
The article describes the method of calculation of hydrodynamic forces acting on the rigid body, completely submerged in the liquid from falling on them of the shock wave. Use a linear (acoustic) setting for the plane problems. On the basis of analogy with the geometrical theory of diffraction, solutions in the form of diffraction integrals of the problems of diffraction of acoustic plane shock wave on the circuit   with the angles and smooth convex circuit. These solutions are cross-checked with the previously known results for a wedge, end, parabolic cylinder.
Key words: wave equation, diffraction, plane acoustic shock wave, diffraction integral.

SOME TRENDS OF DEVELOPMENT OF NAVAL TECHNIQUE

Rozhdestvensky K. V., Kormilitsin Y. N.
State University of St. Petersburg
e-mail: kvrxmas@yahoo.com
tel.: (812) 714-29-23
This paper represents a digest of the materials of the journal  Naval Forces (No. II/2011, Vol. XXXII) on combined warship power plants with hybrid electric drive and on phased radar arrays.
Key words: combined shipboard propulsive plants, integrated of electric system, shipboard radar stations.

ON FREE FLEXURAL VIBRATIONSOF THINCIRCULAR RING OF VARIABLE THICKNESS

Komsomolsk-on-Amure State Technical University
e-mail: taranukha@knastu.ru
tel.: (4217) 54 30 74
In ANSYS program complex an influence of variable thickness on natural frequencies and modes of infinitely long shell (thin ring in plane deformation conditions) is studied.
It is established, that ring’s thickness variation could lead to splitting of frequency spectrum undesirable from dynamic strength’s standpoint. Thereby, the lowest of split natural frequencies is always smaller, not bigger, than ideal ring’s natural frequency as it is considered nowadays.
The refinement of traditional mathematic model is offered. The results of a new theoretical analysis proved numerical experiment’s data, on both quantitative and qualitative levels..
Key words: thincircular ring, a smallthickness variation, the splitting ofthe frequency spectrum.

THE MATLAB-TOOLBOX FOR GUARANTEED ACCURACY DIGITAL CONTROL SYSTEM FOR MARINE DYNAMIC PLANT SYNTHESIS

Rybinskii V. O.
State Marine Technical University of St. Petersburg
e-mail: fishka33@mail.ru
tel.: (812) 714-06-24
The Matlab-toolbox, realizing the stochastic synthesis procedure of the guaranteed accuracy digital controller for the marine dynamic object (MDO) control in a case when external disturbance parameters are not completely known is considered. Such case in practice of control systems design for MDO is typical. The synthesis algorithm is based on the concept of parametrical transfer function. The computing delay, various types of digital-to-analog converters, and also a number of important restrictions for practice are considered in toolbox. Numerical examples are given.
Key words: sampled-data systems, digital control, optimal systems, system with delay, general digital-to-analog converter.

STEAM TURBINE’S OPERATIONAL MODE  OF SEA GAS CARRIER

Semenyuk A. V., Garmash S. A., Semenyuk L. A.
Maritme State University named after G. I.Nevelskoi
e-mail: asemenuk@msun.ru
tel.: (423)2301257
The results of the experimental research of the steam turbine plant modes of the ship carrying liquefied natural gas in terms of «Sakhalin-2» project. Cargo evaporation process is analyzed and this result in forming Boil off gas (BOG) which is used as fuel for steam turbine plant (STP). Criterions are developed to estimate and regulate BOG and Forced off gas (FOG) ratio which is necessary for providing definite ship’s operational mode. Theoretical conclusions are compared to the ship’s operational modes of the ship and power plant. Experimental data of the main turbine redactor gear, which operated within the load 4 year, analyzed in terms of in statistics. Thermal process steam expansion in the turbine in the most typical operational modes has been analyzed.
Key words: liquefied natural gas, gas carrier, ship’s steam turbine, experimental research, expansion process, operation  mode, boil off gas, forced off gas, power.

PROJECT ANALYSIS OF STORM SEAWORTHINESS CONDITIONS

Khramushin V. N., Tsarev B. A.
State Marine Technical University of St. Petersburg
e-mail: v.khram@gmail.com
tel.: (812) 494-09-69
Storm seaworthiness is seen as a complex property. To provide it you have to make certain shape characteristics and body dimensions, engine and propulsion options, choose the right equipment. Proposed a specific form of assessing the level of seaworthiness.
Key words: storm seaworthiness, body shape, ships, walls, boules, wave height, engine and propulsion options.

NEW ENGINEERING APPROACHES IN THE DESIGN OF SELF-GENERATIVE FILTERS FOR CLEANING FUELS AND LUBRICANTS ON BOARD THE SHIPS

Kicha G. P., Pak N. K.
Maritme State University named after G. I.Nevelskoi
tel.: (423) 251-46-69
e-mail: Kicha@msun.ru
A design is given and functioning of a self-regenerative filter in modulus with counter current regeneration for fine cleaning of combustible-lubricant materials on board the ships is described. A scheme of connection it into the lubricating system of the internal combustion engine with cleaning of flushing fluid by centrifuging is shown. Characteristics of wire cloth filters of a new generation for self-regenerative cleaners are proposed. The analysis of motor efficiency of the self-regenerative filter while cleaning engine oil in a medium speed engine is presented.
Key words: self regenerative filter, filtering material, lubrication system, fuel preparation, diesel engine, motor lube oil.