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Development of Equilibrium Flow CFD Code Using CEA Database and Prediction on Ablation of SiC Coating Nozzle : CEA 데이터베이스를 활용한 평형 유동 CFD 코드 개발 및 SiC 코팅 노즐의 삭마량 예측
| DC Field | Value | Language |
|---|---|---|
| dc.contributor.advisor | 김규홍 | - |
| dc.contributor.author | 배지환 | - |
| dc.date.accessioned | 2017-10-31T07:32:51Z | - |
| dc.date.available | 2017-10-31T07:32:51Z | - |
| dc.date.issued | 2017-08 | - |
| dc.identifier.other | 000000146084 | - |
| dc.identifier.uri | https://hdl.handle.net/10371/137338 | - |
| dc.description | 학위논문 (석사)-- 서울대학교 대학원 공과대학 기계항공공학부, 2017. 8. 김규홍. | - |
| dc.description.abstract | This study was conducted with the aim such as development of ablation model of SiC due to combustion gas inside nozzle, prediction on ablation of SiC coating nozzle, development of ablation analysis code. For this purpose, equilibrium flow analysis code using CEA database and a structural temperature distribution analysis code had been developed and the reliability of the code had been secured by carrying out the validation process. These codes were coupled by transferring the wall heat flux and wall temperature as boundary conditions to each other, and the flow/structure integrated analysis code was developed. In order to develop the ablation model, the active and passive oxidation characteristics of SiC materials was investigated. The shear erosion model was developed to simulate mechanical ablation and the melting model was developed to simulate thermochemical ablation. The amount of ablation over time was predicted and compared with the measured amount of erosion depth of nozzle test delivered from the Agency for Defense Development. | - |
| dc.description.tableofcontents | 1. INTRODUCTION 1
2. EQUILIBRIUM FLOW CODE DEVELOPMENT 3 2.1. Flow type of a chemically reacting gas 3 2.2. Governing equations for equilibrium flow 4 2.3. Non-dimensionalization of governing equations 6 2.4. Numerical method 8 2.4.1. AUSMPW+ 8 2.4.2. Time integration method : LU-SGS 10 2.4.3. Time integration method : Dual time stepping 12 2.5. Equilibrium flow analysis using CEA database 13 2.5.1. CEA (Chemical Equilibrium with Applications) 14 2.5.2. Free energy minimization method 16 2.5.3. Thermodynamic properties and transfer coefficient of CEA 18 2.5.3.1. Thermodynamic properties of CEA 18 2.5.3.2. Transport coefficients of CEA 18 2.5.4. Equivalent gamma using CEA database 21 2.5.5. Utilization of CEA database 23 2.5.6. CEA output verification 27 2.5.6.1. Monotonic function 27 2.5.6.2. Comparison of CEA GUI program output values and literature values 28 2.5.6.3. Comparison of CEA GUI program output values and output values of bilinear interpolation function using table 29 2.5.7. Precise verification of output values of bilinear interpolation function using table and table significant digits improvement 30 2.5.8. Generalization of Equilibrium Flow Codes 35 3. FLOW/STRUCTURE INTEGRATED ANALYSIS CODE DEVELOPMENT 36 3.1. Flow/structure integrated analysis code outline 36 3.2. Algorithm of flow and structure analysis code coupling 37 3.3. Structural analysis governing equation 38 3.4. Boundary condition of Structure analysis code 42 3.4.1. External boundary surface in contact with air 42 3.4.2. Inner boundary surface 42 4. VALIDATION OF FLOW/STRUCTURE INTEGRATED ANALYSIS CODE 43 4.1. Validation of flow analysis code 43 4.1.1. NASA CDV Nozzle study 44 4.1.2. Validation of hypersonic flow on flat plate 48 4.2. Validation of structure analysis code 51 5. ABLATION MODEL 55 5.1. SiC oxidation 55 5.1.1. Passive oxidation 55 5.1.2. Active oxidation 56 5.1.3. Active to Passive Transition 57 5.2. Mechanical ablation model 61 5.3. Thermochemical ablation model 61 5.3.1. Equilibrium gas kinetics ablation model 61 5.3.2. Melting erosion model 67 6. ANALYSIS OF ADDs NOZZLE ABLATION TEST RESULTS 69 7. PREDICTION OF ABLATION USING INTEGRATED ANALYSIS CODE 71 7.1. Grid generation for flow and structure analysis 71 7.1.1. Flow analysis grid 71 7.1.2. Structure analysis grid and input material properties by position 72 7.2. Structure material properties correction 75 7.3. Nozzle wall heat flux correction 77 7.4. Physical time step setup 83 7.5. Results of flow/structure integrated analysis code and discussion 86 7.5.1. Results of equilibrium flow field analysis 86 7.5.2. Results of structure temperature distribution analysis 89 7.5.3. Wall heat flux, shear stress, and wall temperature distribution near the nozzle throat 90 7.5.4. Prediction of the amount of SiC coating ablation 92 7.5.4.1. Shear erosion prediction 92 7.5.4.2. Melting erosion prediction 93 7.5.4.3. Total erosion and comparison with measured values 98 8. CONCLUSION 102 9. REFERENCES 104 국문 초록 108 | - |
| dc.format | application/pdf | - |
| dc.format.extent | 8102910 bytes | - |
| dc.format.medium | application/pdf | - |
| dc.language.iso | en | - |
| dc.publisher | 서울대학교 대학원 | - |
| dc.subject | CFD | - |
| dc.subject | equilibrium flow | - |
| dc.subject | CEA | - |
| dc.subject | ablation | - |
| dc.subject | SiC | - |
| dc.subject | SiO2 | - |
| dc.subject.ddc | 621 | - |
| dc.title | Development of Equilibrium Flow CFD Code Using CEA Database and Prediction on Ablation of SiC Coating Nozzle | - |
| dc.title.alternative | CEA 데이터베이스를 활용한 평형 유동 CFD 코드 개발 및 SiC 코팅 노즐의 삭마량 예측 | - |
| dc.type | Thesis | - |
| dc.contributor.AlternativeAuthor | Jihwan Bae | - |
| dc.description.degree | Master | - |
| dc.contributor.affiliation | 공과대학 기계항공공학부 | - |
| dc.date.awarded | 2017-08 | - |
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