Recent Submissions

Now showing 1 - 5 of 13
  • Item
    Current density in a group of long parallel conductors
    (IOP Publishing, 2019-09-11) Coufal, Oldřich
    An original method is proposed for the calculation of current density in a finite number of long parallel solid conductors of arbitrary cross section. Some pairs of the conductors under examination can be connected to a voltage source; they are active. The other conductors are passive. The currents, voltages and magnetic fields are assumed to be quasi-stationary and the displacement current is neglected. The permeability of the conductor material is constant and equals the vacuum permeability. No method has so far been published that would allow an exact calculation of current density in all the cases that satisfy the above assumptions. The application of the method is demonstrated by solving an example with two active conductors, one of which is of circular and the other of rectangular cross section, while a third passive conductor is of rectangular cross section.
  • Item
    Techno-economic comparison of various renewable energy sources for hybrid system implementation
    (International Society for Science and Engineering, o. s., 2021-08-17) Černý, Tomáš; Ptáček, Michal
    The current trends in electro-energetics indicate, that due to depletion of fossil fuels and the need of CO2 emission reduction, there is and will be a substantial development in the fields of renewable energy sources, decentralization and accumulation of electricity using battery energy storage systems in the near future. Along with the increasing power demand and penetration of renewables into electric grids, there is a need for energy mix expansion. Hybrid renewable energy sources (HRES) combine several renewables and energy storage into one system and can be used for micro-grid implementation for off-grid application or on-grid. The article is focused mostly on off-grid systems and provides an information about current state of renewable energy sources applications in HRES with techno-economic evaluation of net present cost and levelized cost of energy.
  • Item
    Measurement of (n,) reaction cross section of W-186-isotope at neutron energy of 20.02±0.58 MeV
    (Council of Scientific & Industrial Research - National Institute of Science Communication and Information Resources, 2020-05-30) Mehta, M.; Singh, N.L.; Makwana, R.; Subhash, P.V.; Suryanarayana, S.V.; Parashari, S.; Chauhan, Rakesh; Singh, R.K.; Naik, H.; Mukherjee, S.; Soni, B.; Khirwadkar, S.; Varmuža, Jan; Katovský, Karel
    The cross-section of 186W(n,)187W reaction has been measured at an average neutron energy of 20.02±0.58 MeV by using activation technique. The 27Al(n,)24Na and 115In(n,n´)115mIn reactions have been used for absolute neutron flux measurement. Theoretically the reaction cross-sections have been calculated by using the TALYS-1.9 code. The results from the present work and the EXFOR based literature data have been compared with the evaluated data and calculated data from TALYS-1.9 code.
  • Item
    Measurements of 181Ta(n,2n)180Ta reaction cross-section at the neutron energy of 14.78 MeV
    (Council of Scientific & Industrial Research - National Institute of Science Communication and Information Resources, 2020-04-30) Soni, B.; Parashari, S.; Mukherjee, S.; Makwana, R.; Mehta, M.; Chauhan, Rakesh; Suryanarayana, S.V.; Pasha, I.; Danu, L.S.; Naik, H.; Nayak, B.K.; Varmuža, Jan; Katovský, Karel
    The cross-section of the 181Ta(n,2n)180Ta reaction has been measured with respect to the 197Au(n,2n)196Au monitor reaction at the incident neutron energy of 14.78± 0.20 MeV, using neutron activation analysis and off-line -ray spectrometric technique. The present measurement has been done at the energy where discrepant measured results are available in the EXFOR data library. The result has been compared with evaluated data libraries JEFF-3.3 and ENDF/B-VII.1. The present result has also been supported by theoretical predictions of nuclear model code TALYS1.8 and TALYS-1.9. The uncertainty and the correlations among the measured cross-section has been studied using co-variance analysis.
  • Item
    Generated heat by different targets irradiated by 660 MeV protons
    (Council of Scientific & Industrial Research - National Institute of Science Communication and Information Resources, 2020-04-30) Svoboda, Josef; Adam, Jindřich; Foral, Štěpán; Gustov, S.A.; Katovský, Karel; Kushvatov, J.; Král, Dušan; Solnyshkin, Alexander A.; Tichý, Pavel; Tyutyunnikov, S.; Zeman, Miroslav
    Calorimetric experiments have been performed to analyze different thick targets of natU, C, Pb material, irradiated by 660 MeV protons at the Phasotron accelerator facility, Joint Institute for Nuclear Research (JINR) in Dubna, Russia. The method of online temperature measurement has been compared with MCNPX 2.7.0 simulation and selected with Ansys Transient Thermal Simulation to compare measured temperature with the simulated one. Thermocouples type T and E have been used as a temperature probe. Many different positions have been measured for each target. Temperature results are following very well the processes inside of the cylinders. Changes of heat deposition caused by drops of the proton beam intensity are displayed very well as a jagged line shown in almost every chart. Accurate temperature changing measurement is a very modest variation of how to observe inner macroscopic behavior online.