Experimental Investigations of the Performance of a Multitube Pulse Detonation Turbine System

A multitube pulse detonation combustor consisting of eight unvalved tubes arranged in a can-annular configuration was integrated with a single-stage axial turbine nominally rated for 10 lbm/s, 25,000 rpm and 1000 hp. The multitube pulse-detonation-combustor-turbine hybrid was operated using ethylene-air mixtures for runs of 5+ min to achieve thermal steady state in order to quantify performance at two operating conditions using simultaneous and sequential firing patterns. Analysis of these data reveal that turbine efficiency under pulse-detonation-combustor-fired operation was indistinguishable from steady performance within the +/- 8 points measurement uncertainty. Furthermore, the pulse-detonation-combustor-turbine hybrid system demonstrated a potential 25% improvement in efficiency once corrections were made for the suboptimal fueling design, which resulted in lower-than-anticipated combustion efficiency. The present work is promising as it suggests that a pulse-detonation-combustor-turbine hybrid engine performance benefit can be realized with further development.