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The Calculation of the Contact Force and the Contact Width of Shaft Seals

Abstract

The aim of the article is to point out the sealing efficiency of the two-language seal of the water pump bearing when radially deflecting the shaft within radial clearance. In order to obtain a radial displacement of the shaft at a location under a two-language seal, dynamic bearing simulation was performed using the MSC Adams program. The largest radial deviation of the shaft was applied in final seal analysis where the contact pressure changes on the individual tongues of the seal were recorded.

Open access
Mechanical and Wear Properties of Friction Stir Welded 0–6Wt% nAl2O3 Reinforced Al-13Wt%Si Composites

Abstract

Friction Stir Welding (FSW) of an Al-13%Si alloy matrix reinforced with 0, 3 and 6 wt% Al2O3 nanoparticles (nAl2O3) is performed and the optical microstructures, tensile strength, hardness and sliding wear properties of friction stir welded joints are investigated and compared to those of base materials. Four different zones of distinct appearances were observed during FSW, which exhibited altered microstructures in the nugget zone (NZ), thermo mechanically affected zone (TMAZ), heat affected zone (HAZ), and base material zone (BMZ). The ultimate tensile strength of the base materials and their welded joints were found to be increasing with increased wt% of nano-alumina reinforcements. High joint efficiency of 89-97% was achieved in FSW. Hardness and wear resistance of friction stir welded joints were found to be better than those of the base materials.

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Do not be Afraid of Small High-Speed Francis Turbines

References [1] https://en.wikipedia.org/wiki/Viktor_Kaplan [2] Original technical documentation of Prokopa & sons comp. [3] Nechleba, M. Hydraulic Turbines, Their Design and Equipment, Constable & Co Ltd. , 1957, 70 - 71 [4] Energy Loss and Efficiency of Power Transmission Belts, Advanced Engineering Research, Carlisle Inc. , pp. 8, Fig. 4 [5] IEC 60193, Hydraulic Turbines, Storage Pumps and Pump-Turbines - Model Acceptance Tests , pp. 30 [6] IEC 60041, Field

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Analysis of the Effect of the Addendum Modification Coefficient for Contact Surfaces of Spur Gear

, 1980 . [12] Terplán, Z. “Gépelemek IV.”, Kézirat, Tankönyvkiadó, Budapest, 1975 , p. 220. [13] Páczelt, I., Szabó, T., Baksa, A. “A végeselem módszer alapjai”, Miskolci Egyetem, 2007 , p. 243. [14] Radzevich, S. P. “Dudley’s Handbook of Practical Gear Design and Manufacture”, Third edition, CRC Press, 2016 , p. 656, ISBN 9781498753104 [15] Alexandru, A. T. “Addendum modification of spur gears with equalized efficiency at the points where the meshing stars and ends” , MECHANIKA 21(6), pp. 480 – 485, 2015 . [16] Thoan P. V., Wen

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Internal Combustion Engine Powered by Synthesis Gas from Pyrolysed Plastics

18-20, 2010, Tatranské Matliare, High Tatras, Slovak Republic. 9 th International Scientific Conference: Energy-Ecology-Economy (EEE) 2010 , Proceedings on CD, ISBN 978-80-89402-23-6, Paper address: CD/files/Eee/5/4, 22 pages. [4] CEVIZ M. A., ÖNER I. V., KAYA F., KARACALI T.: Analysis of the thermal efficiency and cyclic variations in a SI engine under lean combustion conditions, Journal of Thermal Science and Technology , 2011, pp. 121-127, ISSN: 1300-3615 [5] CHRÍBIK A., POLÓNI M., LACH J., JANČOŠEK Ľ., KUNC P., ZBRANEK J.: Synthesis gas from

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Detection and Modeling Vibrational Behavior of a Gas Turbine Based on Dynamic Neural Networks Approach

References [1] A. Zadeh Shirazi, M. Hatami, M. Yaghoobi, S. J. S. M. Chabok. An intelligent approach to predict vibration rate in a real gas turbine. Intelligent Industrial Systems 2016 (2), No. 3, 253 - 267. [2] A. Hafaifa, M. Guemana, A. Daoudi. Vibration supervision in gas turbine based on parity space approach to increasing efficiency. Journal of Vibration and Control 2015 (21), 1622 - 1632. [3] S. Madhavan, J. Rajeev, C. Sujatha, A. S. Sekhar. Vibration based damage detection of rotor blades in a gas

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Development of a cryogenic condenser and computation of its heat transfer efficiency based on liquefaction of nitrogen gas

required cold in the inside slots of the condenser. The refrigerant gas must have its normal condensation point below that of the gas being liquefied. The present article highlights the development of a cryogenic condenser in detail and its efficiency testing methodology in-situ by placing it in the Cryogenerator for liquefying nitrogen. 2 Material and Methods 2.1 Material selection Materials should be prudently selected for any cryogenic application as there can be extreme changes in the properties of the material being used when exposed to low temperature

Open access
Airline Quality Assessment Methodology Taking Into Account the Flight Safety Level Based on Factor Analysis

Abstract

In this article, the authors offer a methodology for determining the quality of airline performance by taking into account the level of flight safety on the basis of factor analysis and the results of methodology approbation in the conditions of a functioning airline. The assessment of the level of airline performance quality taking into account the level of flight safety within a certain time span is rather sensitive, informative and reliable. They allow us to detect those changes in industrial and economic conditions and factors that are related to a certain degree of potential deterioration of flight safety. This creates conditions for revealing the tendencies towards the deterioration of flight safety at the stage of their origin, when they have not yet caused deep, irreversible changes in the flight safety of an airline.

Open access
Evaluation of Management System Effectiveness in the Preparation of the Aircraft for Flight in Faulty Conditions

Abstract

Most flight delays in aviation enterprises are related to air traffic management and technical centers. This can happen for various reasons: untimely removal of defects, lack of spare parts, deficiencies in maintenance scheduling, etc. Another reason may be inefficient management in the system of preparing the aircraft for departure. The article suggests a possible option of such an assessment as well as the results obtained from the use of this methodology applied to a specific airline.

Open access
Differential Evaluation of Crew Functional Effectiveness

Abstract

The aim of this article is the development of the system and methodology of complex control and evaluation of vehicle operators performance during multifunctional simulation. In order to achieve the above-stated aim it is necessary to solve the following principal tasks: to elaborate a theoretical model of differentiated evaluation of vehicle operator training degree according to different kinds of their functional performance; to develop the method of the differential evaluation of crew performance on full-scale aviation simulators with due consideration of the probabilistic approach on the basis of statistical processing of the data of recorded flight information. The offered theoretical model of the differential evaluation of operator performance and the methodology of standards determination developed on its basis represent a new approach to the creation of automated systems for the objective evaluation of the trainees’ qualification degree. The elaborated system of differential evaluation standards ensures a high degree of objectiveness when evaluating the degree of the vehicle operator qualification and makes it possible to carry out a comparative analysis of the operators’ qualification.

Open access