Preliminary Comparison of the Performance of Thermodynamic Models of the Subsonic Ejector and Turbofan

Abstract

Flow-mixing is common in technological processes, and both ejectors and turbofans can produce an interaction between flows with different energy potentials. Ejectors have been extensively used, and their analytical models have been widely presented. To the best of the authors’ knowledge, there is a lack of studies exploring the efficiencies of turbofans. The goal of this paper is to compare thermodynamic processes in these devices. Their efficiencies are compared in terms of compression and entrainment ratios. A comprehensive one-dimensional subsonic thermodynamic models of the ejector and turbofan are presented. The quantitative indices are obtained for the same initial conditions expressed as the ratio of differences in enthalpies for ideal compression and ideal expansion. When initial conditions are equal to the numeric value of the combination of the isentropic efficiency of the evaluated components (numerical case 0.16), both devices have the same efficiencies; at lower initial conditions (numerical case 0.10), a turbofan’s entrainment ratio is 1.5 times and compression efficiency 1.25 times higher; at higher values of initial conditions (numerical case 0.28), the ejector is more efficient. Such distinctive characteristics of turbofans and the nature of their variation may correspond to the specific application areas of technological equipment that require certain flow-mixing parameters.

Compact High Efficiency and Zero-Emission Gas-Fired Power Plant with Oxy-Combustion and Carbon Capture

“…Zero-dimensional calculations of the stationary operation of the spray-ejector condenser, as well as of other flow machines, are based on algebraic models of mass, momentum, and energy balance [122][123][124][125].…”

Vėjo energiją naudojančio turbininio ventiliatoriaus termodinaminis modelis

“…Disertacijos tema paskelbti 8 straipsniai: du -Clarivate Analytics Web of Science duomenų bazėse referuojamuose leidiniuose, turinčiuose citavimo rodiklį (Rimdžius et al, 2021;Martinaitis et al, 2020); keturi -tarptautinių konferencijų leidiniuose, referuojamuose Clarivate Analytics duomenų bazėje Proceedings Streckienė et al, 2021;Streckienė et al, 2018;Januševičius et al, 2017), vienas -kitų tarptautinių duomenų bazių leidiniuose , vienaskonferencijų pranešimų medžiagoje (Sketerskis, Rimdžius, & Martinaitis, 2018). Europos patentų biure įregistruotas patentas .…”

“…Skyriaus tematika paskelbtos keturios publikacijos (Rimdžius et al, 2021;Martinaitis et al, 2020;Streckienė et al, 2021;Streckienė et al, 2018).…”

“…A total of 8 articles have been published on the subject of this dissertation: two of them in publications peer-reviewed in the Clarivate Analytics Web of Science databases with a citation index (Rimdžius et al, 2021;Martinaitis et al, 2020); four, in conference publications peer-reviewed in the Clarivate Analytics Proceedings database Streckienė et al, 2021;Streckienė et al, 2018;Januševičius et al, 2017); one, in publications of other international databases ; one, in conference report materials (Sketerskis, Rimdžius, & Martinaitis, 2018). One patent has been registered with the European Patent Bureau .…”