Numerical solution on the effects of bluff body with slit in micro-channel combustor

Small-scale electronic devices required long hours operation and fast charging time. Potential technology to support requirement of small-scale electronic device is micro scale combustor. Production of heat in micro level from progression of exothermic chemical reaction between reactants is known as...

全面介紹

Saved in:
書目詳細資料
主要作者: Wan Shuib, Wan Mohd Amin
格式: Thesis
語言:English
English
出版: 2018
主題:
在線閱讀:http://ir.upnm.edu.my/id/eprint/253/1/NUMERICAL%20SOLUTION%20ON%20%2825p%29.pdf
http://ir.upnm.edu.my/id/eprint/253/2/NUMERICAL%20SOLUTION%20ON%20%28Full%29.pdf
標簽: 添加標簽
沒有標簽, 成為第一個標記此記錄!
id my-upnm-ir.253
record_format uketd_dc
spelling my-upnm-ir.2532023-09-05T03:03:35Z Numerical solution on the effects of bluff body with slit in micro-channel combustor 2018-09-26 Wan Shuib, Wan Mohd Amin TJ Mechanical engineering and machinery Small-scale electronic devices required long hours operation and fast charging time. Potential technology to support requirement of small-scale electronic device is micro scale combustor. Production of heat in micro level from progression of exothermic chemical reaction between reactants is known as micro combustion and may be utilized to generate electricity for small-scale electronic devices. Unfortunately, micro scale combustion is prone to combustion instability. This research is to study micro scale combustion with slit. Therefore, objective of this study is to investigate the combustion characteristics, mechanism that stabilize the flame and combustor performance of the 2-D microchannel combustor with bluff body having various slit percentages gap using ANSYS Fluent 15.7. Effects of the bluff body with slit in the micro-channel combustor have been studied numerically. Two-dimensional computational domain with the height and length of the channel H = 1 mm and L = 16 mm is used respectively. The height of the bluff body is 0.5 mm and located at 2 mm from the inlet. The slit gap percentage varied in this study is 0% to 70%. The percentage of the slit size is the ratio between slit gap height and the bluff body height. The one-step reaction mechanism of CH4/air mixture is utilized. Equivalence ratios of 0.8 to 1.0 with inlet velocities 1.0 m/s to 5.0 m/s were used. The results show that the combustion characteristic such as stable flame, wavy flame, blow-off and flame split into two parts is significantly influenced by the slit gap percentage. Flame is moving downstream and blow-off at the slit percentage of 10% to 25%. At the slit percentage of 30%, the flame zone moves towards the upstream result in stable flame. From the observation is suggested due to the secondary vortex exist behind the bluff body as slit gap increases and pull or push the flame to the upstream or downstream. The reaction zone is split into two parts at 60% and 70% slit gap percentage. It is due to the incoming fresh mixture of CH4/air mixture flows through the slit and cut the flame zone. It is also found that by increasing inlet velocity beyond 2.0 m/s, the flame become unstable and lead to blow-off as increase in equivalence ratio up to 1.0. Lastly, the highest emitter efficiency is found for the case of 40% slit which is 25 W/m. 2018-09 Thesis http://ir.upnm.edu.my/id/eprint/253/ http://ir.upnm.edu.my/id/eprint/253/1/NUMERICAL%20SOLUTION%20ON%20%2825p%29.pdf text en public http://ir.upnm.edu.my/id/eprint/253/2/NUMERICAL%20SOLUTION%20ON%20%28Full%29.pdf text en validuser mphil masters Universiti Pertahanan Nasional Malaysia Centre For Graduate Studies
institution Universiti Pertahanan Nasional Malaysia
collection UPNM Institutional Repository
language English
English
topic TJ Mechanical engineering and machinery
spellingShingle TJ Mechanical engineering and machinery
Wan Shuib, Wan Mohd Amin
Numerical solution on the effects of bluff body with slit in micro-channel combustor
description Small-scale electronic devices required long hours operation and fast charging time. Potential technology to support requirement of small-scale electronic device is micro scale combustor. Production of heat in micro level from progression of exothermic chemical reaction between reactants is known as micro combustion and may be utilized to generate electricity for small-scale electronic devices. Unfortunately, micro scale combustion is prone to combustion instability. This research is to study micro scale combustion with slit. Therefore, objective of this study is to investigate the combustion characteristics, mechanism that stabilize the flame and combustor performance of the 2-D microchannel combustor with bluff body having various slit percentages gap using ANSYS Fluent 15.7. Effects of the bluff body with slit in the micro-channel combustor have been studied numerically. Two-dimensional computational domain with the height and length of the channel H = 1 mm and L = 16 mm is used respectively. The height of the bluff body is 0.5 mm and located at 2 mm from the inlet. The slit gap percentage varied in this study is 0% to 70%. The percentage of the slit size is the ratio between slit gap height and the bluff body height. The one-step reaction mechanism of CH4/air mixture is utilized. Equivalence ratios of 0.8 to 1.0 with inlet velocities 1.0 m/s to 5.0 m/s were used. The results show that the combustion characteristic such as stable flame, wavy flame, blow-off and flame split into two parts is significantly influenced by the slit gap percentage. Flame is moving downstream and blow-off at the slit percentage of 10% to 25%. At the slit percentage of 30%, the flame zone moves towards the upstream result in stable flame. From the observation is suggested due to the secondary vortex exist behind the bluff body as slit gap increases and pull or push the flame to the upstream or downstream. The reaction zone is split into two parts at 60% and 70% slit gap percentage. It is due to the incoming fresh mixture of CH4/air mixture flows through the slit and cut the flame zone. It is also found that by increasing inlet velocity beyond 2.0 m/s, the flame become unstable and lead to blow-off as increase in equivalence ratio up to 1.0. Lastly, the highest emitter efficiency is found for the case of 40% slit which is 25 W/m.
format Thesis
qualification_name Master of Philosophy (MPhil)
qualification_level Master's degree
author Wan Shuib, Wan Mohd Amin
author_facet Wan Shuib, Wan Mohd Amin
author_sort Wan Shuib, Wan Mohd Amin
title Numerical solution on the effects of bluff body with slit in micro-channel combustor
title_short Numerical solution on the effects of bluff body with slit in micro-channel combustor
title_full Numerical solution on the effects of bluff body with slit in micro-channel combustor
title_fullStr Numerical solution on the effects of bluff body with slit in micro-channel combustor
title_full_unstemmed Numerical solution on the effects of bluff body with slit in micro-channel combustor
title_sort numerical solution on the effects of bluff body with slit in micro-channel combustor
granting_institution Universiti Pertahanan Nasional Malaysia
granting_department Centre For Graduate Studies
publishDate 2018
url http://ir.upnm.edu.my/id/eprint/253/1/NUMERICAL%20SOLUTION%20ON%20%2825p%29.pdf
http://ir.upnm.edu.my/id/eprint/253/2/NUMERICAL%20SOLUTION%20ON%20%28Full%29.pdf
_version_ 1813223594136698880