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arXiv · 2208.07687

A 1D Model for the Unsteady Gas Dynamics of Ejectors

Jan Van den Berghe·Bruno R. B. Dias·Yann Bartosiewicz·Miguel A. Mendez
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Abstract

We propose a 1D unsteady model for supersonic single-phase ejectors. The model treats an ejector as a pipe network with two inputs and one output and combines a 1D gas dynamics formulation in each `pipe' with a junction model for entrainment and mixing. The model is calibrated and validated on experimental data in steady-state conditions and used to analyze the choking mechanism for the mixed flow. The model was then benchmarked against 2D URANS simulations to predict the ejector response to a sudden change in operating conditions, producing traveling waves. The results show that the model can correctly predict the ejector performance and the stream-wise evolution of relevant integral quantities (e.g. mass flow rates and momentum) in both steady and transient conditions.

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Jan Van den Berghe, Bruno R. B. Dias, Yann Bartosiewicz, Miguel A. Mendez. 2022-08-16. A 1D Model for the Unsteady Gas Dynamics of Ejectors. https://doi.org/10.1016/j.energy.2022.126551

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