Study on The Effect of Bluff Body with Slit in the Micro-Channel Combustor

W. M. A. W. Shuib; Azam Che Idris; Mohd Rashdan Saad; Mohd Faizal Hasan; Mohd Rosdzimin Abdul Rahman

Authors

W. M. A. W. Shuib Department of Mechanical Engineering, Faculty of Engineering Universiti Pertahanan Nasional Malaysia, Kem Sg Besi, 57000 Kuala Lumpur, Malaysia
Azam Che Idris Department of Mechanical Engineering, Faculty of Engineering Universiti Pertahanan Nasional Malaysia, Kem Sg Besi, 57000 Kuala Lumpur, Malaysia
Mohd Rashdan Saad Department of Mechanical Engineering, Faculty of Engineering Universiti Pertahanan Nasional Malaysia, Kem Sg Besi, 57000 Kuala Lumpur, Malaysia
Mohd Faizal Hasan Automotive Development Centre, Institute for Vehicle System and Engineering, Faculty of Mechanical Engineering Universiti Teknologi Malaysia, 81310 Skudai Johor, Malaysi
Mohd Rosdzimin Abdul Rahman Automotive Development Centre, Institute for Vehicle System and Engineering, Faculty of Mechanical Engineering Universiti Teknologi Malaysia, 81310 Skudai Johor, Malaysia

Keywords:

Micro-channel combustion, bluff body with slit, CH4/air mixture, laminar

Abstract

Effect of the bluff body with slit in the micro-channel combustor has been numerically studied. Two-dimensional computational domain with the height and length of the channel is H = 1 mm and L = 16 mm were used. The height of the bluff body is 0.5 mm and located at 2 mm from the inlet. The slit gap percentage utilized in this study is 0% to 70%. Percentage of the slit size is a ratio between slit gap height and the bluff body height. The one-step reaction mechanism of CH4/air mixture is used. Results of the numerical work shows that the combustion characteristic is significantly influenced by the slit gap percentage. The highest emitter efficiency is for the case of 5% slit. Moreover, increase in slit percentage to 10%, the flame zone is moving downstream. Later, as the slit percentage increase to 30%, the flame zone moves towards the upstream. This observation is suggested due to the secondary vortex exist behind the bluff body as slit gap increases and pull the flame to the upstream. This study is helpful to improve the understanding on the micro-channel combustion with slit bluff body.