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PL
Niniejszy artykuł przedstawia wyniki obliczeń parametrów konstrukcyjnych skraplacza, przy pomocy wybranych wzorów kryterialnych. W badaniach użyto trzech różnych modeli dla skraplacza rurowo-płaszczowego o gładkiej powierzchni rurek. Jednego modelu dla skraplacza o żebrowanej powierzchni rurek oraz jednego dla wymiennika płytowego. Obliczenia zostały wykonane dla modelu termodynamicznego i parametrów pracy sprężarkowej pompy ciepła 5 MWt pracującej na czynniku chłodniczym R1336 mzz(Z). W wyniku badań udało się ocenić wpływ współczynników korekcyjnych na uzyskany wynik powierzchni wymiany ciepła oraz jednostkowego obciążenia cieplnego. Porównano również wyniki dla skraplacza o rurach gładkich, żebrowanych oraz płytowego. Badania są częścią projektu NCBiR realizowanego przez Wytwórnię Urządzeń Chłodniczych „PZL-Dębica" S.A.
EN
The paper presents the outcomes of calculations related to the design parameters of a condenser, uti lizing specific criterial equations. Three different models were used in the study for a smooth shell-and—tube condenser, another one for a finned tube condenser, and one for a plate heat exchanger. The calculations were per- f formed for a thermodynamic model and the operating parameters of a 5 MWt heat pump compressor working with the refrigerant R1336 mzz(Z). The research yielded insights into how correction coefficients influence the resulting heat exchange surface and specific heat load. Results for each of analyzed variants were also compared. The research is part of the NCBiR project carried out by the WUCh "PZL-Dębica" S.A.
EN
Currently over then 16 percent of the total worldwide salt production is excavated in underground mines. Salt deposits often lie at great depths up to 1000 m, where the temperature of the surrounding rocks reaches 50°C and even exceeds it. A large part of it is exploited using mechanical methods, mainly with the use of road headers and continuous miners. When excavating salt rock, the cutters of the road header mining head come into contact with the rock. This generate friction and in consequence a rise in temperature. In AGH University of Science and Technology the laboratory tests were carried out to determine the effect of temperature on cutting resistance and selected mechanical properties of rock salt. On the special laboratory test stand the rock salt sample was cutted at three different temperatures - 20, 50 and 80°C. The cuttability index and the side chipping angle were measured for each temperature. Additionally the same tests were performed in the case of salt sample after cooling to room temperature. The selected mechanical parameters of rock salt - compressive, tensile and shear strength were also measured for the same temperature values. The obtained results were compared and described in the paper.
EN
Hyperloop is a new concept of transport system the main assumption of which is to use hermetic tunnels where air pressure is very low compared to atmospheric pressure. It enables significant reduction of traffic resistance and, as a result, energy consumption. One of the most important elements of this system is land infrastructure with transport tubes. This system component has a significant impact on the construction costs related to the whole system and affects its functional parameters (e.g. capsule travel speed). Appropriate configuration of the route of a new transport system will require the use of all possible ways of leading transport tubes, including tunneling. The paper presents the key premises that prove a large potential application of tunnel technologies in the development of a new transport system.
PL
W artykule przedstawiono koncepcję głowicy dyskowej nowej generacji oraz dotychczasowy zakres badań stanowiskowych związany z jej doświadczalną weryfikacją. Przedstawiono podstawowe zagadnienia będące przedmiotem aktualnych badań modelowych związanych z rozwojem konstrukcji głowicy, w tym modelowaniem dynamiki układu napędowego oraz symulacją obciążeń narzędzi dyskowych.
EN
he article presents a concept of the new generation mining head with disc tools and current scope of research related to experimenal verification. In the article the basic issues that are the subject of current simulation modeling are presented related to the development of the head construction, including modeling of dynamics of power transmission system and the simulation of disk tool loads.
EN
Underground salt mining accounts for about 16 percent of the total salt production worldwide. When excavating salt rock, the cutters of the road header come into contact with the rock. This produces friction and, consequently, a rise in temperature. Generally, as temperature increases, salt gradually loses its plasticity. The extent of these alterations depends on the presence of other minerals in the rock. This paper presents the results of laboratory tests on regularly shaped samples of salt. An analysis was performed of the results of compressive, tensile and induced-shear strength, and of Young's modulus, Poisson's ratio, cuttability index and side chipping angle. The testing was conducted on samples with a temperature of about 20°C and samples heated to 50°C and 80°C. The tests showed that as temperature increased, so did compressive and tensile strength, and longitudinal and transverse strain of salt. The temperature increase caused, however, a decrease in shear strength. The cuttability index and the side chipping angle also decreased when the heated samples were being cut. The percentage changes in the parameters within the 60-degree temperature range were as high as several dozen percent.
6
Content available Drive simulation tests for electric drilling rig
EN
The article presents methodology and selected results of simulation tests of diesel and electric dive system for drilling rig. Research in this field were conducted under the project no. POIR.01.01.01-00-D011/16 entitled „New generation of modular rigs, drilling and bolting, with battery drives, designated to work in underground cooper ore and raw rock material mines”. The project is funded by the National Center of Research and Development (NCBiR). The aim of the project is to design and implementation of innovation drilling and bolting rig with electric drive system. Due to the complexity of the structure of the drive system (mechanical, hydraulic and electrical elements), it was necessary to use advanced simulation software dedicated to multiphysics analysis. Data presented in the article can be used as guidelines in design process of drilling and bolting rigs as well as in optimization their driving system and mechanical construction.
PL
Tematyka eksploatacji pokładów cienkich jest obecnie jednym z głównych obszarów zainteresowań producentów oraz użytkowników zmechanizowanych kompleksów ścianowych. Wynika to z faktu, iż niezależnie od szeregu czynników górniczo-geologicznych, które w różnym stopniu mogą wpływać na możliwości techniczne prowadzenia ścian niskich, kwestia wzrostu koncentracji wydobycia z pokładów cienkich jest powiązana przede wszystkim z konstrukcją odpowiednio przystosowanych do ekstremalnie trudnych warunków maszyn zmechanizowanego kompleksu ścianowego. Szczególnie istotną rolę w tego typu warunkach eksploatacyjnych odgrywają cechy konstrukcyjne obudów zmechanizowanych. W artykule przedstawiono projekt nowej sekcji obudowy zmechanizowanej do pokładów cienkich oraz wyniki badań stanowiskowych z jej udziałem. Prace badawcze w tym zakresie zostały zrealizowane w ramach projektu pt. „Prace studialne i badawcze nad opracowaniem zmechanizowanej obudowy nowego typu do pokładów cienkich” dofinansowanego z Narodowego Centrum Badań i Rozwoju (NCBiR).
EN
The subject of thin seam exploitation is a complex problem; in reality, it involves several problems such as technical, ergonomic, and economic barriers. They refer mainly to combined longwalls – where a human presence is required at the site; the most important problem is the issue of the limited workspace in longwall roadways. This generates engineering and organizational problems, especially during the launching and removal of the longwall roadways. Having considered the above-mentioned, the Department of Mining, Dressing, and Transport Machines at AGH in Krakow has begun research whose main objective is to develop and test a new structure for a powered support for thin seams. In this paper, virtual models of the new hydraulic roof support and a conception of the structure of a control system were presented as well as the test results of the new construction hydraulic roof support. Research in this field was conducted for the project entitled “Studies of the Development of an Innovative Hydraulic Roof Support for Low Seams”. The project is funded by the National Center of Research and Development (NCBiR).
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