Technical Transactions. Vol. 7

Technical Transactions. Vol. 7

Type: Collection of magazine numbers
Release date

Collection items (21)


Modelling of production processes with the use of witness simulator

Zwolińska, Bożena
Article
2017
Customization of final products forces the so-called “make-to-order” production. In the article, there is a presentation of influence of EPEI changes (Every Part Every Interval indicator) on the efficiency and effectiveness of complex production system. The use of Witness System Simulation Modeling helped to create the model of real object which has been validated in the real work parameters. All of the times of the realized processes have been simulated as random variables with certain density of probability distribution.

Virtual prototyping of electro-hydraulic parallel manipulator control systems

Woś, Piotr, Dindorf, Ryszard
Article
2017
The paper presents the process of virtual prototyping of a parallel manipulator which uses electro-hydraulic servo-mechanisms to drive active elements. A mechatronic solution of tasks of forward and inverse kinematics with the use of a virtual model of the manipulator, as well as a control system for the virtual machine were presented herein. The solution presented in the article makes it possible to study the functions of the control system before its merger with a real manipulator. At the same time, the design process is significantly accelerated.

Numerical analysis of damage in silica filled epoxy products using XFEM and its verifications

Płatek, Robert, Malinowski, Łukasz, Zwoliński, Piotr
Article
2017
The paper summarizes the study of cracking phenomena in silica filled epoxy material. Numerical analyses of cracking phenomena were performed using Extended Finite Element Method (XFEM) for a full scale element as well as in a microscale, for the Representative Volume Element (RVE). Experimental verification consists of both C2 tests for real products and in-situ tensile tests and microstructural observations with the Scanning Electron Microscope (SEM). At the end, a summary with conclusions related to the prepared numerical analyses and experiments is included.

Application of numerical calculations in the design process of hydrodynamic torque converter

Osowski, Karol, Kęsy, Andrzej, Kęsy, Zbigniew, Olszak, Artur
Article
2017
The use of numerical calculations to assess the impact of construction parameters on properties of a hydrodynamic torque converter has been presented in the article. The calculations have been based on a verified mathematical model of the transmission system including a hydrodynamic torque converter.

Evaluation of particle size distribution of aggregates in asphalt concrete by means of image analysis software

Piątek, Paweł
Article
2017
Analysis of (cylindrical) samples of asphalt concrete, in terms of weight and size distribution of different fractions of aggregates and by means of mechanical methods is a complicated and time consuming process. This article presents a proposal of a method for the same kind of analysis, but without the need for machining. The suggested method is based solely on a computer based analysis of photographs of the samples. The mechanism described in this paper is only a preliminary process, illustrating the potential use of an image analysis for this type of study.

Mobile remote monitoring system of water reservoirs

Opaliński, Andrzej, Głowacki, Mirosław
Article
2017
The article presents the concept, architecture and testing of mobile monitoring system of water reservoirs. Its main elements are a remotely controlled boat with a sonar, which additionally records GPS data. The developed system could be used in several configurations for the achievement of functions such as generating bathymetric maps or the current monitoring of the bottom of a water reservoir. The main functionalities of the system have been tested and presented with the results of the tests and their analysis, conclusions and plan of further development.

Flow simulation in hydrodynamic torque converter

Migus, Marcin, Kęsy, Andrzej, Kęsy, Zbigniew
Article
2017
The paper compares the theoretical non–dimensional steady–state characteristics of a hydrodynamic torque converter with the experimental ones. The theoretical characteristics were calculated numerically based on two flow models: a one–dimensional model created by the authors and a three–dimensional model prepared by means of the ANSYS CFX software. The experimental characteristics were obtained on the basis of test rig investigations.

Evaluation of pressure losses reduction possibility for WEH22 directional control valve by internal geometry correction

Lisowski, Edward, Rajda, Janusz
Article
2017
The article presents the evaluation of possibility of pressure losses reduction at the flow through a WEH22 hydraulic directional control valve. For this purpose, 3D models of flow paths were built using the Creo Parametric software. Then the models were used in the ANSYS/Fluent software to calculate pressure losses. The results of the analysis have allowed for determination of possibilities of pressure losses reduction without changing overall dimensions of the valve body.

The adaptation of the cross validation aproach for RBF-based collocation methods

Krowiak, Artur, Podgórski, Jordan
Article
2017
The paper shows the adaptation of the cross validation approach, known from interpolation problems, for estimating the value of a shape parameter for radial basis functions. The latter are involved in two collocation techniques used on an unstructured grid to find approximate solution of differential equations. To obtain accurate results, the shape parameter should be chosen as a result of a trade-off between accuracy and conditioning of the system. The cross validation approach called “leave one out” takes these aspects into consideration. The numerical examples that summarize the investigations show the usefulness of the approach.

Cutting forces during precise turning of NiTi shape memory alloy

Kowalczyk, Małgorzata
Article
2017
The selected indicators of machinability of NiTi based shape memory alloys has been examined. The paper presents research of possibilities of shape memory alloy like low-temperature (austenitic) Ni53Ti47 (Nitinol) with a coated cemented carbide tool, cutting force components (Ff – the feed force, Fp – the passive force, Fc – the main cutting force). In the work, a special attention was paid on the main cutting force components at variable cutting speed (vc).