수소-메탄 연료의 가스 터빈 단일 노즐 예혼합 화염의 유동 및 연소 특성 = Flow and combustion characteristics of hydrogen-methane premixed flame in a gas turbine nozzle

다국어 초록 (Multilingual Abstract)

As global energy demand rises, gas turbine power generation is receiving considerable attention. However, gas turbines emit pollutants such as NOx and CO during operation. Hydrogen is a carbon-free fuel and offers high energy density per unit mass, but it also leads to issues such as flashback and high NOx formation due to its high flame speed and flame temperature. For this reason, research on micromix combustors has expanded in recent years.
In this study, a single nozzle of a micromix combustor was evaluated through numerical and experimental approaches. Mixing between fuel and oxidizer was evaluated using mole-fraction comparison, unmixedness, uniformity index, and non-uniformity index, and the mixture was found to be well mixed. Combustion and emission characteristics were evaluated experimentally. The results show that increasing the hydrogen fraction expands the flame stability region. Hydrogen has a flame stability region more than 25 times wider than methane. Flames containing methane appear blue due to CH* emission, while hydrogen flames show a reddish color because no carbon is present. As for emissions, higher hydrogen content increased peak NOx due to higher flame temperature, while CO decreased because of reduced carbon in the fuel and enhanced OH radical formation.

목차 (Table of Contents)

• 제 1 장 서론 1
• 1.1 연구배경 1
• 1.2 연구목적 3
• 제 2 장 배경 이론 및 선행 연구 4
• 2.1 배경이론 4
• 2.1.1 수소 연료 4
• 2.1.2 마이크로믹스(Micromix) 연소 6
• 2.1.3 화학종 분포 가시화 7
• 2.1.4 NOx 생성 메커니즘 8
• 2.2 선행연구 11
• 제 3 장 연구방법 13
• 3.1 수치해석적 연구 13
• 3.1.1 해석 조건 13
• 3.1.2 격자 독립성 평가 17
• 3.1.3 격자 검증 17
• 3.1.4 혼합도 평가 19
• 3.2 실험적 연구 21
• 3.2.1 연소 시스템 21
• 3.2.2 화염 가시화 24
• 3.2.3 배기성능 평가 27
• 제 4 장 결과 및 고찰 29
• 4.1 연료 조성에 따른 혼합도 평가 29
• 4.2 연소 성능 평가 35
• 4.2.1 화염 안정성 영역 평가 35
• 4.2.2 화염 가시화 37
• 4.3 배기성능 검토 42
• 제 5 장 결론 49
• 참고문헌 51