비정렬 혼합 격자계에서 격자 변형 기법을 이용한 가변노즐 유동 해석

다국어 초록 (Multilingual Abstract)

In the present study, unsteady flow simulations of a variable geometry nozzle were conducted using a two-dimensional flow solver based on hybrid unstructured meshes. The variable geometry nozzle is used to achieve efficient performances of aircraft engines at various operating conditions. To describe the motion of the variable geometry nozzle, an algebraic method based on the basis decomposition of normal edge vector was used for the deformation of viscous elements. A ball-vertex spring analogy was used for inviscid elements. The aerodynamic data were obtained for a range of nozzle pressure ratios, and the validations were made by comparing the present results with available experimental data. The unsteady nozzle flows were simulated with an oscillating diverging section and a converging-diverging section. It was found that the nozzle performances are influenced by the nozzle exit flow characteristics, mass flow rate, as well as unsteady effects. These unsteady effects are shown to behave differently depending on the frequency of the nozzle motion.

참고문헌 (Reference)

1 이희동, "비정렬 혼합 격자계에서 신속 격자 변형 기법을 이용한비정상 점성 유동 해석" 한국전산유체공학회 14 (14): 33-48, 2009

2 Johnson, D., "Variable Jet Propulsion Nozzle"

3 Bottasso, C.L., "The Ball-vertex Method: A New Simple Spring Analogy Method for Unstructured Dynamic Meshes" 194 : 4244-4264, 2005

4 Sasanapuri, B., "Numerical Study of a Supersonic Cruise Nozzle" AIAA 2013

5 Hunter, C.A., "Experimental, Theoretical and Computational Investigation of Separated Nozzle Flows" 20 (20): 1219-1227, 1998

6 Carson, G.T.Jr., "Experimental and Analytical Investigation of Axisymmetric Supersonic Cruise Nozzle Geometry at Mach Numbers From 0.60 to 1.30" NASA 1981

7 Park, D.C., "Development of Synchronization Test System for a Variable Nozzle" 130-131, 2011

8 Dalbello, T., "Computational Study of Axisymmetric Off-Design Nozzle Flows" NASA 2003

9 Carson, J.R., "Computational Prediction of Isolated Performance of an Axisymmetric Nozzle at Mach number 0.90" NASA 1994