Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 7

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

An Optimization Study of a Hydraulic Gear Pump Cover with Finite Element Method

100%
Ozsoy M., Kurnaz C.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 3
944-948
EN
In this study, an optimization analysis of the hydraulic gear pump cover with design of experiments and response surface method has been conducted. The sample of the solid cover of a hydraulic pump has been parametrically modelled. Structural strength analysis of the modelled hydraulic pump cover has been realized using finite element method. To prevent the concentration of stress on the hydraulic pump cover and to keep the stress values on the safe side, design inputs were not exceeded. According to the analysis results of this optimization study; the wall thickness of the hydraulic pump cover has been reduced. Finally, experimental tests were performed on hydraulic pump test setup, for verification of the simulation results.
2
Content available remote

Calculations of Temperature Rise in Al, Cu and Fe Photon Collimators for 8-32~MeV Photon Beams

81%
Kuluöztürk Z., Demır N., Akkurt İ.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 3
1168-1170
EN
We have focused on temperature changes in the collimator at the TARLA bremsstrahlung photon facility. One of the important parameters during the design of an ideal collimator, especially for high-energy photons, is temperature rise in the collimator material. For this purpose, energy deposition in the collimator materials was simulated using the FLUKA Monte Carlo code. Depending on energy deposition values, temperature rise in the collimator materials of Al, Cu and Fe was calculated for photon beams with 8-32 MeV energies.
3
Content available remote

Monte Carlo Simulation Studies of Collimator Parameters for TARLA Bremsstrahlung Facility

81%
Kuluöztürk Z., Demır N., Akkurt İ.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 3
796-800
EN
In this work, calculations of the design of bremsstrahlung photon collimator within the scope of the Turkish Accelerator Center Project are presented. At TARLA facility (Turkish Accelerator Radiation Laboratory at Ankara), bremsstrahlung photons created by the accelerated electron beams, are transferred to the experimental area through the collimator, which has a conical geometry with length of 320 cm. In this study, Al, Fe and Cu materials were selected as collimator materials. All interactions between the collimator materials and Gaussian photon beam in 8-32 MeV energy range (8 MeV, 16 MeV, 24 MeV and 32 MeV) were taken into account. The entry radius, geometry and chosen materials are important parameters for collimator design. The photon fluence from collimator, secondary particle distributions and the number of photons, scattered from the collimator, were calculated as functions of these parameters. All calculations were made with the Monte Carlo code FLUKA. According to the results of these simulations, collimator with conical geometry, made of aluminium, with 0.25 cm entry radius, was determined to be appropriate for TARLA bremsstarhlung photon facility of Turkish Accelerator Center.
4
Content available remote

Ionisation Efficiency in Conical Hot Cavities

61%
Turek M.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 2
259-263
EN
Surface ionisation in a new type of hot cavity characterised by the shape of a truncated cone is considered in the paper. Influence of the hot cavity shape and its temperature on the ionisation efficiency of stable and long-lived nuclides is under investigation and the supremacy of elongated conical cavities is proven. The role of the extraction opening size is studied and its optimal diameter ( ≈ 1 mm) is found for the considered cavity shapes. It is shown that the extraction voltages of 1-2 kV are large enough to obtain high efficiencies and saturation of the current-voltage curves is observed above these values. Changes of ionisation effciency with the ioniser temperature are investigated - increase of ion yield with T is observed. It was proven that cold spots inside the ioniser cavity (near the extraction opening - in the considered case) can degrade ion source performance by several tens percent.
5
Content available remote

Design of a Laboratory Unit Air-Conditioning System with Matlab/Simulink Software

61%
Koçyığıt N., Şahın M.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 3
839-842
EN
In this study, design of an electronic air-conditioning system was carried out using Matlab/Simulink software. The air-conditioning system was designed as a laboratory experimental setup. The aim of this study was to revise and to reuse an outdated air-conditioning laboratory unit, by using improved methods. General equations were defined separately for each part and cell of this air conditioning system. Using these equations Matlab/Simulink models for every component were created. The Matlab/Simulink models were combined and verified with theoretical results. The simulation results show that theoretical results are compatible with the simulation results. These results were tested for input and output air enthalpy values and for humidity values. In addition, air mass flow rates for the number of different fan speeds were compared. The coherent simulation results showed that the general model of the air conditioning system, designed in Matlab/Simulink, behaves correctly. This model will be used in the future studies for comparison of real system results with simulation results.
6
Content available remote

Two-Dimensional Simulations of H¯ Ions Extraction

52%
Turek M.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 2
254-258
EN
The 2D particle-in-cell method based model of a negative ion source is presented. The spatial distributions of electrostatic potential and plasma component densities are presented. Changes of negative ion distribution and potential as well as the extracted H¯ current with the plasma grid bias voltage are investigated. The presence of the potential well near the plasma grid surface that traps the negative ions is shown. Increase of the H¯ ions density inside the chamber with the negative bias voltage is demonstrated. Influence of the H¯ ion flux outgoing from the plasma grid on the extracted current was checked: increase by factor 2 is observed when the flux rises 4 times. Current-voltage characteristics of the ion source are presented, saturation of the curve is observed above 50 kV.
7
Content available remote

Extreme gravitational lensing in vicinity of Schwarzschild-de Sitter black holes

52%
Bakala P., Čermák P., Hledík S., Stuchlík Z., Truparová K.
Open Physics
|
2007
|
vol. 5
|
issue 4
599-610
EN
We have developed a realistic, fully general relativistic computer code to simulate optical projection in a strong, spherically symmetric gravitational field. The standard theoretical analysis of optical projection for an observer in the vicinity of a Schwarzschild black hole is extended to black hole spacetimes with a repulsive cosmological constant, i.e, Schwarzschild-de Sitterspacetimes. Influence of the cosmological constant is investigated for static observers and observers radially free-falling from the static radius. Simulations include effects of the gravitational lensing, multiple images, Doppler and gravitational frequency shift, as well as the intensity amplification. The code generates images of the sky for the static observer and a movie simulations of the changing sky for the radially free-falling observer. Techniques of parallel programming are applied to get a high performance and a fast run of the BHC simulation code.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.