A Review of Recent Patents on Micro-Combustion and Applications

Micro-combustion is being investigated for potential application in aerospace propulsion, electricity generation and heating. Simultaneously to studies focusing on scientific aspects of micro-combustion, inventions concerned with micro-combustor configurations and methods of carrying out sustained micro-combustion in them have appeared in the recent past. In order to gauge the current state of art in this important area, and also to provide a concise summary of some significant technological developments to date, patented inventions on micro-combustion and its applications are reviewed in this paper. Key features of the inventions tentatively classified according to the three application areas are described while revealing their significance by carrying out a comparative study of patents and non-patent literature. This study considers performance parameters, scope of envisaged applications and complexity of configuration. Allied areas of micro-machining (MM) and electricity generation have also been discussed. A major objective is to identify factors, which could decide future progress of micro-combustion, and to this end; the review indicates that low achievable overall efficiency is a major bottleneck in application of micro-combustion technology. Consequently, further development of reasonably tested devices will depend upon progress made in the down-stream energy converters. Finally, an outlook on the future developments is also presented.