Investigation of Interface Oscillations during Boiling = Divfāzu robežas svārstības pētīšana vārīšanās procesā

Veikti fāzu robežas svāratību eksperimentāli un teorētiski pētijumi burbuļa augšanas procesā uz sildvirsmas . Eksperimenti tika veikti ar ūdeni atmosfēras spiediena apstākļos lielā tilpumā . Ar lāzera un akustisko diagnostiku tika fiksētas tvaika burbuļa tilpuma un formas svārstības . Apskatīto vienādojumu sistēmas skaitliska risinājuma rezultātā iegūti tvaika burbuļa svārstību fāzu portreti . Konstatēts ka tvaika burbuļa augšanu pavada tilpuma svārstības kuras noteiktos apstākļos kļūst haotiskas , par to liecina Ļapunova kritēriji , divi no kuriem ir pozitīvi . Iegūta eksperimentālo un teorētisko rezultātu atbilstība

Shell-and-Tube or Plate Heat Exchangers

The calculations of heat and hydraulic characteristics and influence of apparatus with intensifiers size analysis to heat exchanger potential of equipment were made onto the basis of known experimental data recommendations. Calculations data were received in a range of parameters, that are typical for a heat and water supply systems. It was obtain, that in studied range of Reynolds’s number, the most better heat transfer coefficient value is for the tubes with dimpled interface with Re<3*10,3 and in case a swirl tubes by Re>3*103. Under the stipulation of scales, the heat transfer coefficient for a swirl tube and tube with circular knurl in a beginning is decreasing, and then comes out on a constant, whereas for a smooth tube – monotonically decrease in time. Pressure losses in heat exchanger with twisted tubes are almost the same as in case of smooth tubes. Pressure losses in heat exchanger with dimpled tubes are less than in case of smooth tubes