MODELING of Rarefied Gas Flows Inside a Micro-Nozzle Based on the DSMC Method Coupled with a Modified Gas–Surface Interaction Model

Bibliographic Details
Title: MODELING of Rarefied Gas Flows Inside a Micro-Nozzle Based on the DSMC Method Coupled with a Modified Gas–Surface Interaction Model
Authors: Xuhui Liu, Dong Li, Xinju Fu, Yong Gao, Xudong Wang
Source: Energies, Vol 16, Iss 1, p 505 (2023)
Publisher Information: MDPI AG, 2023.
Publication Year: 2023
Collection: LCC:Technology
Subject Terms: rarefied flow, wall roughness structure, DSMC method, needle valve opening, molecular number density, thrust force, Technology
More Details: In this study, we first considered the influence of micro-nozzle wall roughness structure on molecular collision and reflection behavior and established a modified CLL model. The DSMC method was used to simulate and analyze the flow of the micro-nozzle in the cold gas micro-propulsion system, and the deviation of simulation results before and after the improvement of CLL model were compared. Then, the rarefied flow characteristics under a small needle valve opening (less than 1%) were focused on the research, and the particle position, molecular number density, and spatial distribution of internal energy in the micro-nozzle were calculated. The spatial distributions of the flow mechanism in the micro-nozzle under different needle valve openings were compared and analyzed. It was found that when the needle valve opening is lower than 1%, the slip flow and transition flow regions move significantly upstream of the nozzle, the free molecular flow distribution region expands significantly, and the relationship between thrust force and needle valve opening is obviously different from that of medium and large needle valve openings. The effect of nitrogen temperature on the rarefied flow and thrust force is also discussed in this research. The numerical results showed that as gas temperature increases, the molecular internal energy, momentum, and molecular number density near the nozzle exit are enhanced. The thrust at small needle valve openings was significantly affected by the temperature of the working mass. The results of this study will provide key data for the design and development of cold gas micro-thrusters.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1996-1073
Relation: https://www.mdpi.com/1996-1073/16/1/505; https://doaj.org/toc/1996-1073
DOI: 10.3390/en16010505
Access URL: https://doaj.org/article/8bc19f21a8b145b98d89fb55ef66f416
Accession Number: edsdoj.8bc19f21a8b145b98d89fb55ef66f416
Database: Directory of Open Access Journals
Full text is not displayed to guests.
More Details
ISSN:19961073
DOI:10.3390/en16010505
Published in:Energies
Language:English