METHODS OF CFD MODELLING OF TWIN-SCREW PUMPS FOR NON-NEWTONIAN MATERIALS

The twin-screw pump is designed for pumping highly viscous materials in the food industry. Rheological characteristics of materials are important in the specification of design parameters of screw pumps. Analysis of flow in the twin-screw pumps with definition of non-newtonian materials can be made by numerical modelling. CFD generally oriented software ANSYS Fluent and ANSYS Polyflow has been used for modelling. In this study those software’s (ANSYS Fluent and ANSYS Polyflow) were defined for solution of flow in the twin-screw pumps. Results were compared for the same boundary conditions on the inlet and outlet of the 3D model. For definition of the viscosity were used the Nonnewtonian power law. Parameters as consistency coefficient and flow exponent for Nonnewtonian power law were analysed by software ANSYS Fluent and ANSYS Polyflow. Postprocessing form ANSYS Fluent and ANSYS Polyflow were made by contours of field and by graphs.

DISIMILLAR LAP JOINT FRICTION STIR WELDING (FSW) USING VARIED LENGTH OF PIN

The lap joint will be used on aluminum 6061 and 10 mm thick brass with the Friction Stir Welding method. The probe used is EMS 45 steel with variations in pin lengths of 11 mm, 11.5 mm and 12 mm. The results of this study are in length 11.5 mm with the highest Vickers hardness value of 104.26 VHn compared to 11 mm and 12 mm pin length is 98.93 VHn and 70.43 VHn. The results of shear stress are 67.32 MPa at 12 mm pin length, higher than the 11 mm and 11.5 mm pin lengths of 40.2 MPa and 42.14 MPa.

EVALUATION OF COMBINED PRODUCTION OF HEAT AND ELECTRICITY ON THE COGENERATION UNIT

The purpose of currently contribution is to analyse and compare effectivity of cogeneration unit in each summer and winter season. The main idea of combined heat and energy production is to reduce usage of primary fuels and with that connected reduction of pollutions due to the integration of renewable energy sources and with regard to the natural environment. Presented contribution is dedicated on issue on the operation of a cogeneration unit integrated in central heating system.

NUMERICAL MODELLING OF OSCILLATING FLOW FOR ENERGY HARVESTING

The energy efficiency of systems, equipment, and sensors is nowadays intensively studied. The new generation of microelectronic sensors is very sophisticated and the energy consumption is in the microwatts range. The energy to power the microelectronic devices can be harvested from oscillating flow in small size channels and so replaceable batteries could be eliminated. Piezoelectric elements can convert energy from oscillation to electrical energy. This paper focuses on the simulation of periodic flow in the fluidic oscillator. CFD simulations were performed for several values of the flow rate. Experimental measurement was carried out under the same conditions as the CFD experiment. The main monitored and evaluated parameters were volume flow rate and pressure loss. Fluid oscillations were analysed based on CFD simulations and the theoretical maximum energy available for the deformation of piezoelectric elements and transformable into electrical energy was evaluated.

REDUCTION OF METAL CATIONS CONTENT FROM THE AQUEOUS SOLUTIONS BY SORBENTS

The article presents the results of research on reducing the concentration of heavy metals, such as copper and nickel, on natural zeolite in comparison with synthetic zeolite and chemically treated natural zeolite. The reduction of the content of specific types of heavy metals from aqueous solutions was investigated by the method of sorption kinetics. The results indicate the ability of natural zeolites to compete with synthetic zeolites.

THE COMBUSTION ENGINE INTAKE MANIFOLD CFD MODELING DEPENDING ON THE AIRBOX CONFIGURATION

The aim of the article is to present the possibilities of application of computational fluid dynamics (CFD) to modelling of air flow in combustion engine intake manifold depending on airbox configuration. The non-stationary flow occurs in internal combustion engines. This is a specific type of flow characterized by the fact that the variables depend not only on the position but also on the time. The intake manifold dimension and geometry strongly effects intake air amount. The basic target goal is to investigate how the intake trumpet position in the airbox impacts the filling of the combustion chamber. Furthermore, the effect of different distances between the trumpet neck and the airbox wall in this paper will be compared.

COMPARISON OF BASIC MAINTENANCE CONCEPTS USING WITNESS

Maintenance is a complex, extensive and important issue in terms of its impact on the quality of manufactured products or services provided in all areas of industry. The importance of predictive maintenance for the industry in the 21st century is crucial. However, the right approach to maintenance management is often underestimated in many companies today, although it can have a very positive effect on the company’s efficiency. Using the example of a practical application, the paper includes a comparison of three main maintenance concepts – classical (reactive), planned, predictive through the simulation software Witness. Maintenance concepts are compared in terms of their ability to solve and eliminate failures that occur in production facilities during operation.

CONTROLLED TESTING OF BELT TRANSMISSIONS AT DIFFERENT LOADS

The presented paper provides the alternative options for determining the condition of belt gear based on the testing and monitoring. In order to carry out experimental measurements, a newly developed device for testing, monitoring and diagnostics of belt drives was designed, as well as the possibility of determination of limit states by extreme loads. The designed measuring stand allows to determine the point of destruction of the belt for an extreme load. The process of the belt measurement was to set the predetermined input revolutions of the driving motor by means of the Altivar 71 (FM1) frequency inverter connected to the driving electric motor. The next step in defining the input parameters was to set the load on the driven electric motor. The load on the driven motor was achieved by the torsional moment set by means of the Altivar 71 (FM2) frequency inverter connected to the driven electric motor. In the paper, the analytical calculation is processed. The article mainly points to the innovation of the stand for testing belt transmissions.

A COMPLEX CONCEPTION OF MANAGEMENT SYSTEM OF ORGANISATIONS AND SOCIAL RESPONSIBILITY

The difficult situation is affecting many organisations at the present time. This article mainly deals with ensuring of the quality of production on the example of a case study in one manufacturing organisation. However, it is about involving other aspects, such as: maintenance, social responsibility, process approach. Everything is based on specific findings related to the economic crisis caused by the COVID-19 pandemic. Quality management tools and responsibility tools were applied in solving this complex task. The example of the mentioned organisation shows that the conformity application of aspects of the management system above in a holistic connection to soft resources not only supports the strengthening of production quality and the growth of efficiency, but it also strengthens an internal culture of the organisation. The goal is to ensure an efficient operation of the organisation and thus to support its competitiveness.

RESEARCH AND DEVELOPMENT OF A KNOWLEDGE-BASED DESIGN SYSTEM FOR DESIGNING SELECTED ELEMENTS OF MECHATRONIC DEVICES

The design of mechatronic devices is a demanding process not only in terms of the time required but also of the demands placed on the knowledge and experience of development workers. The aim of this research and development was to create suitable procedures, algorithms, and databases of 3D models, with the help of which could this process be significantly shortened and simplified. The results of the development are a software tool for the design of electric drive units, procedures for creating 3D models with the possibility of using the SolidWorks software API, methods for automating the creation of assemblies of 3D models and a description of the knowledge database in which various data and algorithms are stored. The benefits of the proposed procedures, the Drive Picker software tool, and the knowledge database, are demonstrated on the design of a robotic arm with 5 degrees of freedom. Despite the complexity of the preparation of documents needed, it turns out that the chosen approach can significantly speed up and simplify the design of mechatronic devices.