Scalability and dynamic stability of hybrid rocket engines

This paper is divided in two parts. The purpose of the first part is to tackle the problem of geometrical scalability of hybrid rocket engines while the second part of the paper the stability of hybrid rocket motor is investigated using Liapunov theory. Stability coefficients obtained are dependent on burning parameters while the stability and command matrixes are identified. Thus in the first part of this paper, authors present a method to tackle the issue of scalability in hybrid rocket engines. Experimental results on various hybrid rocket engines will be presented and compared with theoretical results obtained through an original internal combustion model. We derive the influence of hybrid rocket engine scale while keeping the same oxidizer and fuel and geometric similarity. The paper presents thoroughly the input data of the model, which allows reproducing easily the results obtained. The conclusions highlight the results obtained in chapter dedicated to analyze the results.