By means of time resolved and transient computations, the complex opening process of a fast acting valve has been analysed. The computations provide new insight into the complex interaction of the sliding piston with the transient flow. The qualitative agreement of the computed and measured pressure plot is very good. Due to the interaction of piston and flow, additional pressure and expansion waves are induced. However, for the present conditions in the low pressure section, a well established shock was found 1800 mm downstream of the valve. During the experiments repetition rates up to ten shots per hour were accomplished and the shock strength was very well reproduced. By demonstrating a good performance of the valve, this concept is an alternative that combines the advantages of both the arrangement of a conventional shock tube and the reproducibility of other diaphragmless shock tubes. Nevertheless, the results of this work will be used to revise the valve again in order to further improve its performance.
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