Papers by Keyword: Block Diagram

Abstract: The article presents the results of experimental studies of the thermoelectric characteristics of plastically deformed steels ST3, 08KP, 12H18N10T. Measurements in the area of maximum deformation of the samples were carried out. Differences in the thermoelectric characteristics of plastically deformed steels were revealed. Steel 12H18N10T has linear characteristic, and characteristics of steels ST3 and 08KP have extreme. Constant temperature between the hot and cold electrodes needs to be maintained and also the temperature of the test specimens needs to be monitored, which in the differential testing method equals to cold electrodes. Novel block diagram of a device for testing of thermos electromotive force and monitoring of the cold electrodes temperature is proposed.

Abstract: This article is focused on finding the most appropriate solution for eliminating vibrations that pose harmful influences in mechanical systems. To find this solution, the kinetic equations were generated from dynamical model of truck bodybuilding. The block diagram for natural frequencies calculation was made up out of these equations. Two solutions were suggested – to place flexible shaft coupling between high pressure pump and Power Take off and to connect the pump and Power Take Off directly with shaft. It is important to note that vibrations emerging may be reduced more effectively by using of the former solution – flexible shaft coupling.

Abstract: The bond graph modeling method was discovered by Henry Painter in 1959 and has quickly become a wide spread method all over the modeling engineering world. The method is based on the analysis of power circulation in systems and has some indisputable advantages over other modeling methods, based in principle on mathematical aspects. The paper proposes a comparison between the bond graph method and Lagrange's equations method, by applying both methods to model a mechanical system. The bond graph model is a graphical model. There are three possibilities to exploit the bond-graph diagram. The first one consists in deducing a system of differential or algebraic-differential equations from the diagram. The second one consists in obtaining the block diagram model from the bond graph diagram, without additionally writing any equations, followed by the block diagram implementation in the appropriate software, which permits to perform simulations at once. The third one consists in implementing the bond graph diagram directly in the appropriate software, where simulations can immediately run. The advantages and the disadvantages of the methods are emphasized, but the decision about the most appropriate method is up to the modeler.

Abstract: Analytically describing the relationship among steady-state power flow numerical values is a significant proposition. Because the block diagram has the ability to describe the signal transmission analytically, we choose this method to study the steady-state grid’s power transmission rule. Each node or branch is chosen as a basic power transmission unit, and the ratio between the unit’s output power and input power is defined as power transmission gain. The power transmission relationship of each unit can be established according to the circuit analysis, and then the block diagram of each unit can be built on the basis of above relationship. Finally, a block of the whole power grid can be drawn according to the basic units’ connection relationships. The transmission relationship of the whole power grid was analytically expressed by the block diagram simplification method.

Abstract: The paper presents a new approach to the numerical solution of a particle in equilibrium lying on a circle and subjected to the action of a linear spring. The difficulties of solving such a problem and the Mathcad and Simulink based solutions are presented in [1, 2, 3]. The most important difficulties consist in symbolically solving a forth degree trigonometric equation or in solving a complicated trigonometric inequality. This is why a numerical solution is preferred. The use of the bond graph modelling method for solving this problem of equilibrium is presented in this paper. The bond-graph modelling method is designed only for dynamics and the paper presents the possibility of its adaptation for solving this problem of statics of a particle. This approach can be then applied to solve other problems of statics. From the bond graph model the equilibrium equation and the block diagram model can be obtained. The block diagram model is usually preferred in engineering and, for this reason, the block diagram model obtained from the bond-graph model is shown in the paper together with the numerical results obtained after performing the simulations. The results are compared with those previously obtained in [2, 3].

Abstract: In all processing plants there is a great influence to improve the performance of its overall operation, safety, efficiency and production by the need to reduce the failure of its equipment. Equipment failure; even on very rare occasions, can result in great economic and financial losses. As a result of many uncertainties originating from the design and operation of the equipment at a plant there are some failure risks that cannot be avoided. In this article, the reliability of a steel refining process was predicted. Two failure modes were investigated for each type of equipment from which the reliabilities were used to determine the overall plant reliability. The maximum plant reliability was found to be 98.0%. It was noted that even though a high reliability prediction was found, it is important to employ preventative maintenance on the plant to ensure the consistent operation of the equipment and maintain the reliability.

Abstract: Different methods adopted to study the working space of robot other than the traditional software methods, used block diagram in control theory to describe the transfer function of the kinematical chain of robot based on decomposition, digital and logical circuit of electronic technology with the foregoing result, data acquisition of dexterous working space and singular working space can be easily found then.

Abstract: The main flaws of electric arc welds and factors determining the quality of the welded seams are considered in this paper. In practice, welding tools and their control systems are affected by some external factors causing deviation of the weld’s quality from the specified values. Currently used control systems of welding tools do not always satisfy the requirements for quality of welded joints. Major principles of developing the adaptive control system of the welding tool are considered here and the developed functional and block diagrams of microprocessor system are presented. General equations describing the welding process are also provided and the obtained transfer function of a closed system is described.