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The objective of the paper is to study the influence of turbulence on the burning velocity of a lean gas-air mixture at high compression ratio ε = 14.5. In the present work turbulent combustion are examined in conditions very similar to those in the engine. Experiments are carried out in a rapid compression machine. The combustion area in a cylinder is divided into two parts: the main combustion chamber and very small open prechamber containing catalyst with developed surface. The temperature of the catalyst is controlled by means of special electronic device. Special inserts with orifices of different diameters are used to generate turbulence in the main combustion chamber. A piston pushes the mixture through the insert and creates swirl with superimposed different scale of turbulence in this chamber. Mutual influence of turbulence and catalytic ignition on combustion of a lean propane air mixture is extensively examined in special sets of experiments.

Combustion systems with swirl chambers are applied in some spark ignition engines with homogeneous mixture. Such systems are developed to burn lean mixture with increased compression ratio far from the knock limit [1,2]. It was shown that these systems could be significantly improved by employing a prechamber with a catalyst [3,4]. An important part of the discussed combustion systems is cylindrical combustion chamber with a strong swirl. In this chamber, the flame propagates in the field of centrifugal forces increasing with a radius. In such conditions the flame surface takes the form of a cylinder. In the past, in a few experimental studies the behavior of flame propagation was investigated under the action of increased centrifugal forces, but the results were qualitative in nature [5, 6 and 7]. In the proposed paper an experimental study of flame propagating in a mixture with rigid-body rotation was carried out.