초록

• 차세대 원자로 피동냉각계통의 축소형 비상냉각 탱크 장기냉각설비 실험 장치를 구축함
• 장기냉각설비용 수직형 쉘(응축)-튜브(공기)타입 열전대튜브형 공랭식 응축열교환기 개념 제시
• 순수증기일 때 응축열전달계수 측정실험 수행 및 응축열교환기 설계변수 영향 연구

(출처 : 보고서 요약서 3p)

Abstract ▼

Recently, passive cooling systems have been assigned great importance given their contribution to improve the safety in the design of next-generation nuclear power plants(SMART, APR+ etc.). It is necessary to use emergency cooldown tank for a passive cooling system. The capacities of these emergency

Recently, passive cooling systems have been assigned great importance given their contribution to improve the safety in the design of next-generation nuclear power plants(SMART, APR+ etc.). It is necessary to use emergency cooldown tank for a passive cooling system. The capacities of these emergency cooldown tanks are designed to be sufficient to remove the sensible and residual heat from the reactor coolant system over 72 h by the installation of an air-cooled condensing heat exchanger on the top of the emergency cooldown tank, so that the water level can be maintained by collecting the steam from the tank. In this project, the following main items will be researched for the design of an air-cooled condensing heat exchanger.
1. Setup of an air-cooled condensing heat exchanger of long-term passive cooling system in emergency cooldown tank
2. Measurement of both local condensation heat transfer coefficient at inner tube wall and local air-side natural convective heat transfer coefficient in a tube mounting thermocouples
3. Study of deterioration of condensation heat transfer with non-condensable gas
4. Suggestion of prototype of shell and tube type air-cooled condensing heat exchanger

Experiments are conducted to examine the passive cooling system of a scaled-down emergency cooldown tank to validate the concept of long-term passive cooling. It is obligatorily required to use shell and tube type air-cooled condensing heat exchanger to collect evaporating steam from emergency cooldown tank. For this, it is strongly suggested that condensation heat transfer and air-side natural convective heat transfer correlations should be developed. However, it is very difficult to measure surface temperature at a tube without disturbing both condensing and natural air flows. Therefore, we will design a tube mounting thermocouple inside. Moreover, the developed heat transfer correlation will be improved by adding the effect of ambient temperature, the pitch of tubes, non-condensable gas effect, system pressure, etc. Finally, the concept of long-term passive cooling system with installing the air-cooled condensing heat exchanger will be validated.

In the first year, a patent of the design of shell and thermocouple tube was submitted. After conducting air to water condensation experiment, the result was proceeded in ICAPP 2017. Three journal manuscripts were published into Annals of Nuclear Energy and Progress in Nuclear Engineering. Also, we communicated and obtained any helpful feedback from Korean nuclear conference which is held twice a year. We expect two graduating students after finishing the first stage of this project.

The result of this project will be expanded as following:
1. Utilizing the design of air-cooled condensing heat exchanger in passive residual heat removal system and passive containment cooling system for SMART
2. Utilizing the concept of long-term cooling system to extend the operation of passive auxiliary feed water system for APR+
3. Utilizing the design of condensation heat exchanger immersed in emergency cooldown tank
4. This heat exchanging technology can be applied the automobile industry and energy plant with great importance due to their compact size and efficient heat transfer.

(출처 : SUMMARY 6p)

목차 Contents

• 표지 ... 1
• 제 출 문 ... 2
• 보고서 요약서 ... 3
• 요 약 문 ... 4
• SUMMARY ... 6
• CONTENTS ... 8
• 목차 ... 9
• 제1장 연구개발과제의 개요 ... 10
• 제2장 국내외 기술개발 현황 ... 12
• 제3장 연구개발수행 내용 및 결과 ... 15
• 3.1 연구개발수행 내용 ... 15
• 3.1.1 축소형 비상냉각탱크 용량 및 전열기 용량 산정 ... 15
• 3.1.2 공랭식 응축열교환기의 크기 산정 및 제작 ... 16
• 3.1.3 실험장치 및 계측장비 ... 16
• 3.1.4 자연순환 유량측정 장치 ... 18
• 3.2 연구개발수행 결과 ... 22
• 3.2.1 열전대 삽입형 전열관 제작 ... 22
• 3.2.2 축소형 비상냉각탱크 실험장치 ... 24
• 3.2.3 응축열전달 실험수행 ... 26
• 제4장 목표달성도 및 관련분야에의 기여도 ... 32
• 제5장 연구개발결과의 활용계획 ... 33
• 제6장 연구개발과정에서 수집한 해외과학기술정보 ... 34
• 제7장 연구장비의 구축 및 활용 결과 ... 35
• 제8장 참고문헌 ... 36
• 끝페이지 ... 36