In this work, a study was made of methods for converting a real gas from a full-scale compressor to a model one for low-temperature pure methane using the equations of state of a real gas Benedict-Webb-Rubin and Peng-Robinson. In the course of the work, the features of recalculation methods were studied, a model of an air compressor was selected, corresponding in parameters to a model of a low-temperature methane compressor using the theory of similarity, using similarity criteria. Also, in this work, the features of the application of various equations of state were studied when describing the model of a low-temperature methane compressor, as well as the features that arise when this model is converted to an air model analogue. Data were obtained on the possibility of applying the proposed methods on real units, and the invariance of the method with respect to the used equations of state of a real gas for pure methane at temperatures from 150 to 300 K and a division of 0.2 MPa was proved. At the final stage of the work, comparative characteristics of two models of natural methane compressors were obtained, based on different equations of real gas, describing the medium and two models of model compressors using air as a working medium and being model analogs of the above units.
The article presents the experience of calculating and studying of the high-pressure membrane compressor main elements research experience, running on gaseous oxygen. The following issues are considered: determining the distribution and limiting disks surface profile, compressor main loaded elements strength calculation, modeling the temperature distribution in the membrane block during operation. These studies can be useful for further membrane compressor units development and can be used as a basis for calculations and new installations design.
The article deals with the problems of diagnostics of surging phenomena in centrifugal compressors. The reasons for the surge phenomenon and the method for its diagnosis to prevent emergencies are stated. The article describes the phenomenon of rotating stall, which precedes the surge. Diagnostics of the appearance of a rotating stall opens the possibility of predicting the appearance of a surge. This allows for an efficient and safe surge protection system. Solving the problem of developing new principles for constructing surge diagnostics systems. Application of biorthogonal wavelet transform for prebreak detection.
Virtual testing unit description for unsteady flow phenomena investigations in a centrifugal compressor based on ANSYS 12.0 system is presented. Comparisons of calculated and experimental results for steady and unsteady data are acceptable. Transient Blade Row methods (the CFX Transient Blade Row Modeling with the terminology of Turbo component) — is the sector of blades in a given blade row that are being modeled in the analysis. Transient Rotor-stator analyses involve at least two components, one rotating and one stationary component
Моделирование и валидация рабочего процесса в модельной малорасходной ступени центробежного компрессора.
В работе представлены результаты моделирования трехмерного вязкого потока в малорасходной модельной ступени центробежного компрессора. Исследовались расчетные газодинамические характеристики ступени с условным коэффициентом расхода Фопт=0.015 и условным числом Маха Mu=0.784. Ступень рассчитана упрощенно (только рабочее колесо) и подробно с учетом междисковых зазоров и лабиринтных уплотнений у основного и покрывного дисков, безлопаточного диффузора и обратно-направляющего аппарата. Результаты расчета сопоставлены с экспериментальными данными. Получено хорошее совпадение на оптимальных режимах. Произведена оценка применимости упрощенной модели рабочего колеса для определения напорной характеристики.