Experimental Study of Continuous H2/Air Rotating Detonations

ABSTRACT

An experimental study of a lab scale rotating detonation combustor (RDC) has been conducted to identify and classify its modes of operation under different feeding conditions. The chamber uses air as oxidizer and hydrogen as fuel. The stability diagram of the RDC has been determined based on the detonation chamber Reynolds number and reactants mixture equivalence ratio values. The Reynolds number is based on the air volume flow rate, chamber annulus size, and the reactants mixture feeding slot area. Hence the effects of geometrical parameters and operational parameters on the detonation wave stability can be presented in a single stability map. This diagram identifies different zones in terms of the stability, propagation characteristics, and the number of detonation waves. Absence of a stable detonation wave at low Reynolds numbers and observation of different detonation modes with increasing Reynolds number, in different ranges of equivalence ratios, have been established in this research. This paper describes the various modes of rotating detonation wave propagation in the RDC. These modes include the single-wave detonation mode, the dual-waves unidirectional detonation mode, the dual-waves colliding detonation mode, extinguishing and re-initiating detonation mode, and the deflagration mode

KEYWORDS:

• Rotating detonation wave
• propagation modes
• stability map