Browsing by Author "Krumov K.S."

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Energy gains at daily periodic changes of the azimuths of PV modules in north-east Bulgaria
    (2023-01-01) Penkova N.Y.; Krumov K.S.; Hristov P.V.
    The higher efficiency of tracking photovoltaic systems is an indisputable fact and computational methods of the respective energy gains are well known. However the investments in the tracking systems are higher in comparison to the fixed ones due to the needs of additional equipment and automation systems. An options of periodical change of the azimuth of PV modules at single axis solar trackers and the correspondent incident solar energy are studied in this paper. An approach for numerical determination of the daily periods of cyclic rotations of the trackers and the subsequent electricity production is developed. It was applied to estimate the energy gains at such cyclic changes of a PV system in ceramic factory in Bulgaria.
  • No Thumbnail Available
    Item
    Finite elements analysis of mass transfer and mechanical processes in ceramic ware at convective drying
    (2019-09-20) Penkova N.Y.; Mladenov B.M.; Krumov K.S.
    Mathematical models of the coupled moisture diffusion and mechanical processes in ceramic ware at industrial drying are composed. They allow taking into account the impact of the drying regime on the plastic deformation and shrinkage of the articles. The models are validated and applied for numerical investigations of the transient fields of the moisture content, stresses and strains in building bricks in continuous dryers. Ways for their application for improving of the energy efficiency of drying installations are discussed.
  • No Thumbnail Available
    Item
    Multiphysics simulation for design and adjustment of efficient industrial drying modes of ceramic ware
    (2023-01-01) Penkova N.Y.; Mladenov B.M.; Krumov K.S.
    Algorithms for design and adjustment of industrial drying regimes of ceramic ware, based on modeling and numerical simulation of coupled mass transfer and mechanical processes in the dried media, are developed. They allow prediction of efficient drying rate through estimation of the strain-stress processes in the dried bodies based on finite element analysis and experimentally determined material models. Thermodynamically relations are used to obtain and adjust the change mode of the relative humidity, temperature and velocity of the drying gas in the dryers. The proposed approaches were applied for estimation of the possibility for drying time reduction of ceramic bricks in continuous draying installation, and the subsequent technological effects.