Technical Transactions. Iss. 3

Technical Transactions. Iss. 3

Type: Collection of magazine numbers
Release date

Collection items (18)


The impact of deepening the stilling basin on the characteristics of hydraulic jump

Siuta, Tomasz
Article
2018
In this article, the results of computational fluid dynamic (CFD) modelling of the hydraulic jump conditions occurring in the experimental prismatic rectangular stilling basin with sudden crosswise expansion are presented. The FLOW 3D software program was used to numerically solve Reynolds Navier-Stokes (RANS) equations with the application of the k-ε turbulence model. The influence of the depth magnitude of the stilling basin and the ending sill installation on the hydraulic jump turbulent characteristics and submergence condition changes was investigated. Based on the results of the numerical modelling, it was found that various spatial flow processes contribute to the submergence condition of the hydraulic jump. These processes include: crosswise flow expansion within the stilling basin; local tail water surface level increase and total head loss due to vertical flow contraction; installation of the additional terminal sill. This contribution to the submergence condition allows a reduction in the required depth of the stilling basin, calculated on the basis of a one-dimensional simplified approach without consideration to the spatial characteristic of the hydraulic jump.

Technical Transactions. Iss. 3

Number of the magazine
2018

Using fuzzy logic to optimise the selection of mother wavelets

Lagun, Ilona, Nakonechnyy, Adrian, Samotyy, Volodymyr
Article
2018
The effectiveness of signal processing using discrete wavelet transformation depends on the correct choice of basic wavelet function. A model of multi-criteria optimisation of selection of wavelet function was developed based on fuzzy logic. An experimental study of the model was carried out for the most common types of signals selected from the MATLAB database package.

The effect of external mass transfer resistance on the adsorption rate in a liquid phase

Piątkowska, Sylwia, Gwadera, Monika
Article
2018
The paper presents the results of studies on the adsorption of a dye from a water solution on activated carbon. An activated carbon with the best adsorption properties for the dye used in the studies was selected experimentally. The equilibrium and kinetic measurements for the selected system were conducted. Constants of linear, Langmuir and Freundlich isotherms were determined. The obtained results have shown that increasing the flow rate of the solution in an adsorber results in increasing the adsorption rate.

Characteristics of producing ethyl alcohol

Jamróz, Justyna, Jankowski, Dawid
Article
2018
The paper presents the introduction to problems related to the distilling industry in Poland and its current situation. The theoretical issues related to the production of ethyl alcohol are discussed. The raw materials used and their impact on production efficiency, process steps and their conditions and quality requirements for alcoholic beverages based on ethanol are characterised. The main causes of the problem of distillery in Poland are seen in the import of cheap rectified and dehydrated spirits from other EU countries, which results in a fall in market prices that do not provide for reimbursement of production costs and increase of excise duty in 2014, which significantly contributed to the closure of the distillery. At present, there are around 100 of them in the country, most of which are made of distillates for bio ethanol production.

Characterization of risk function in the analysis and assessment of water supply systems safety

Tchórzewska-Cieślak, Barbara
Article
2018
Safety is a term referring to lack of threat, guarantee of liquidation or minimizing threats. With regard to drinking water, consumer safety is understood as the probability of avoiding threat resulting from consuming water with quality that is incompatible with applicable normative or lack of water. However, an assumption that the measure of loss of safety is a risk function has become the paradigm. The classical definition of risk implies that it means the possibility of loss, harm with a certain probability. At the same time, there is a term of uncertainty which means lack of certainty and often refers to lack of safety. The main purpose of this paper is to present methods of analysis and risk assessment and the characterization of risk function in probabilistic and fuzzy (possibilistic) aspect.

Plants as natural anti-dust filters – preliminary research

Mazur, Justyna
Article
2018
In urban areas, particulate matter (PM) are the leading cause of air pollution. They can adversely affect human health. One of the solutions to reduce pollution and improve air quality is the use of plants as natural, biological filters which trap the particles on the leaves. Studies on the assimilation capacity of species (Hedera helix, Parthenocissus quinquefolia, Fagus sylvatica) were analyzed. In addition, based on two examples of structures in Krakow, the storage capacity of vines such as Hedera helix and Parthenocissus quinquefolia and Fagus sylvatica tree, for fraction of PM (0.2–2.5 μm; 2.5–10 μm; 10–100 μm) was estimated. Analyses have shown the particular efficacy of creeping vines in PM capture.

The reliability of rural water distribution systems in relation to the layout of the pipework within the network

Dawidowicz, Jacek, Czapczuk, Andrzej
Article
2018
In this paper, the K readiness index was adopted in order to evaluate the reliability of the rural water distribution system; complete systems were assessed using the partial survey method. Hydraulic calculations were performed, followed by reliability evaluation with our own NSW programme. In addition, the lengths of the ring and branched sections of the analysed water distribution systems were calculated and 256 computational variants were obtained. Taking into account the values of the K readiness index and the cable lengths, the influence of the pipework system on the level of reliability of a water distribution system with a pumping-hydrophore structure was determined. In the case of a branched system, a moderately strong negative correlation was identified between reliability and the length of pipework.

Concept of the development of Oświęcim through an offering of increasing cultural and utilitarian qualities

Paprzyca, Krystyna
Article
2018
The author discusses the city of Oświęcim in terms of the abovementioned aspects, trying to justify that the city of Oświęcim is following the path of development. There are many issues which cover urban renewal through offering an increase of quality: – an improvement of the quality of the public space within a city; the regeneration and modernisation of buildings and technical infrastructure within its Old Town area; – increasing the rest, recreation and tourism offering of the city in areas along the Soła River [16]; – uphold the identity and culture of the area; – use the creative potential that supports economic growth, including the creation of new employment opportunities, creating conditions for new economic investment. Reinforcing the intellectual capital of the city; – use the potential that is Oświęcim’s location at the crossing of transit routes of national and voivodship-level significance.

The determination of mechanical properties of prosthetic liners through experimental and constitutive modelling approaches

Łagan, Sylwia, Liber-Kneć, Aneta
Article
2018
The aim of the study was the estimation of the ability of hyperelastic material models for the fitting of experimental data obtained in the tensile testing of silicone liners used in lower-limb prosthetics. Three groups of liners were analysed: I – silicone liner, II – part of the liner in which the silicone has a fabric reinforcement, III – silicone liner with an outer covering material. Both longitudinal and circumferential samples were taken. The Neo-Hookean, Mooney-Rivlin and Ogden parameters of constitutive models of hyperelastic materials were calculated.