Numerical simulation of effect of obstacles on pulse detonation engine performances

The performance parameters of the single-cycle detonation wave of an ideal pulse detonation engine (PDE) are calculated by solving unsteady two-dimensional (2D) reacting N-S equations, and these parameters are compared with the results obtained from the Wintenberger semi-analytic model. The effects of ring obstacles on the loss of air flowing through the PDE and the performances of single-cycle detonation wave of the PDE are studied. The data of numerical simulation are compared with those of multi-pulse detonation experiments conducted on a 60 mm inner diameter detonation tube. The results show that the calculated impulse is almost the same as the impulse used by the Wintenberger semi-analytic model, which means the numerical simulation method is valid. The blockage ratio increases, or the obstacle pitch and inner diameter ratio decreases, while the total pressure recovery coefficient decreases. The blockage ratio increases, the impulse per unit volume of single-cycle detonation wave decreases and the specific fuel consumption increases. When the blockage ratio is about 41%, the impulse per unit volume is 92% of that of the ideal PDE. The obstacle pitch and inner diameter ratio increases, the impulse per unit volume of single-cycle detonation wave first decreases and then increases, while the specific fuel consumption first increases and then decreases. This effect of different obstacle pitch and inner diameter ratios on PDE performance agrees with that of the multi-pulse detonation experiments.