수증기 개질기의 형상 및 운전조건 변화에 따른 열 유동 및 개질 효율 특성 = Characteristics of heat, flow and reforming efficiency in steam reformer for various geometries and operating conditions

다국어 초록 (Multilingual Abstract)

Hydrogen is considered as a fuel of the future for its renewability and environmental compatibility. The main objective of this paper is to investigate characteristic of steam reformer at various geometries and operating conditions. The steam reforming reaction of natural gas is known to be the most popular technology among the reforming reaction such as ATR and POX. In this paper, the steam reforming is studied by a numerical method and three dimensional simulations were used for effective analytical study. User ？ Defined Function (UDF) was used to simultaneously calculate reforming and combustion reaction. And the numerical model is validated with experimental results at the same operating conditions. In order to understand the relationship between operating conditions such as steam to carbon ratio(SCR), gas hourly space velocity(GHSV), mass flow rate of combustor inlet, various numerical investigations are carries out for various geometries.
Numerical results show that cylindrical geometry is more effective than rectangular geometry for heat transfer to reactors and reforming efficiency. As mass flow rate of combustor inlet increase, reaction occurs more faster and temperature increase with each geometry. In the case of GHSV increase, reaction and conversion rate decrease.
Reforming efficiency, Cylindrical geometry is more effective than Rectangular geometry. When SCR(Steam to Carbon ratio) increases, CO decrease since WGS reaction becomes more active and dry base concentration of H2 is increases.

목차 (Table of Contents)

• TABLE OF CONTENTS
• Abstract I
• Table of Contents III
• List of Tables V
• List of Figures VI
• Nomenclature XI
• 제 1장 서 론 1
• 1.1 연구배경 1
• 1.2 연구동향 10
• 1.3 연구목적 12
• 제 2장 지배방정식 및 관련 이론 16
• 2.1 화학반응 16
• 2.2 다공성 매질 20
• 2.3 지배방정식 23
• 제 3장 전산해석 방법 39
• 3.1 격자생성 39
• 3.2 해석모델 41
• 3.3 초기 및 경계 조건 44
• 제 4장 결과 및 고찰 51
• 4.1 모델검증 51
• 4.2 수증기 개질기의 형상에 의한 영향 52
• 4.2 연소기에 유입되는 유량의 변화에 의한 영향 63
• 4.2.1 사각형 수증기 개질기 63
• 4.2.2 원통형 수증기 개질기 76
• 4.3 GHSV 의 변화에 의한 영향 88
• 4.3.1 사각형 수증기 개질기 89
• 4.3.2 원통형 수증기 개질기 102
• 4.4 SCR 의 변화에 의한 영향 115
• 제 5장 요약 및 결 론 116
• 참고문헌 120