VOLTAGE ASYMMETRY INFLUENCE ON RESOURCE CON-SUMPTION AT POWER GENERATING PLANTS

The objective of this paper is to provide new research on the linkages between voltage asymmetry, energy efficiency, and resource efficiency to inform policymaking in this area about the possibilities of electricity saving potential. Asymmetry voltage coefficients value in Ukrainian grid were experimentally identified based on assessments of 23 Ukrainian companies during 2016-2018. It was estimated, that 26 % of transformers have asymmetry voltage coefficient of reverse sequence lower than 2 % and 12 % of transformers have asymmetry voltage coefficient of zero sequence lower than 2 %. The estimated resource saving potential for Ukrainian power generating plants is up to 1’978 GWhel/a, which is up to 1.5 % of total electricity produced. Equivalent reducing electricity generation at coal power plants could prevent emissions up to 292.79 t/a of ash emissions; 733 kt/a of CO2 emissions; 5.9 kt/a of SOx emissions; 2.9 kt/a of NOx emissions; 9.03 m3/a of nuclear waste.

NEUTRON ENRICHMENT OF THE NECK-ORIGINATED INTERMEDIATE MASS FRAGMENTS IN PREDICTIONS OF THE QMD MODEL

The effect of neutron enrichment of the neck formed during reseparation of two colliding nuclei was studied with the aim to infer an information on the density dependence of the asymmetry energy term in the equation of state. By using a version of the QMD model of Łukasik it is shown that the neutrons-to-protons ratio of the intermediate mass fragments (IMF) emitted from the neck, 〈N/Z〉, is not a sufficiently sensitive observable to discriminate between different assumptions regarding the symmetry term of the equation of state. As an alternative, isotopic ratios of selected pairs of isotopes turned out to be useful observables more sensitive to the assumed form of the symmetry term of the equation of state. A comparison with experimental data on isotopic ratios for beryllium and boron IMFs from the 124 Sn + 64 Ni reaction at 35 MeV/nucleon tentatively suggests that the ASY-SOFT option of the symmetry energy term in EOS is preferred.

GIANT RESONANCES AND ASYMMETRY ENERGY

A microscopic analysis of the asymmetry energy is performed through the investigation of nuclear giant resonances in the relativistic approach. Nuclear ground state properties are calculated in an extended relativistic mean-field theory plus BCS method, where the contribution of the resonant continuum to pairing correlations is properly treated. The nuclear giant resonances are investigated in the relativistic random phase approximation (RRPA) or quasi-particle RRPA. Special emphases are paid to the correlation between the giant dipole resonance or pygmy resonance and the density dependence of the asymmetry energy.