Object-Oriented Approach to Modeling Units of Pneumatic Systems

• Main Authors: Yu. V. Kyurdzhiev, A. V. Chernyshev
• Format: Article
• Language: Russian
• Published: MGTU im. N.È. Baumana 2014-01-01
• Series: Nauka i Obrazovanie
• Subjects: aggregates of pneumatic systems; mathematical models; design scheme; object-oriented pro-gramming
• Online Access: http://technomag.edu.ru/jour/article/view/728

<p>The article shows the relevance of the approaches to the object-oriented programming when modeling the pneumatic units (PU).</p><p>Based on the analysis of the calculation schemes of aggregates pneumatic systems two basic objects, namely a cavity flow and a material point were highlighted.</p><p>Basic interactions of objects are defined. Cavity-cavity interaction: ex-change of matter and energy with the flows of mass. Cavity-point interaction: force interaction, exchange of energy in the form of operation. Point-point in-teraction: force interaction, elastic interaction, inelastic interaction, and inter-vals of displacement.</p><p>The authors have developed mathematical models of basic objects and interactions. Models and interaction of elements are implemented in the object-oriented programming.</p><p>Mathematical models of elements of PU design scheme are implemented in derived from the base class. These classes implement the models of flow cavity, piston, diaphragm, short channel, diaphragm to be open by a given law, spring, bellows, elastic collision, inelastic collision, friction, PU stages with a limited movement, etc.</p><p>A numerical integration of differential equations for the mathematical models of PU design scheme elements is based on the Runge-Kutta method of the fourth order. On request each class performs a tact of integration i.e. calcu-lation of the coefficient method.</p><p>The paper presents an integration algorithm of the system of differential equations. All objects of the PU design scheme are placed in a unidirectional class list. Iterator loop cycle initiates the integration tact of all the objects in the list. One in four iteration makes a transition to the next step of integration. Calculation process stops when any object shows a shutdowns flag.</p><p>The proposed approach was tested in the calculation of a number of PU designs. With regard to traditional approaches to modeling, the authors-proposed method features in easy enhancement, code reuse, high reliability, and low time consuming development. The calculation results of the traditional and authors-proposed approaches are identical.</p>