Fig. 1 Experimental system More

Fig. 2 Combustor head section of the actively valved resonant pulse combustor More

Fig. 3 Time traces of ion signal and pressure signal measured in RPC combustion chamber, and the valve area (dashed line) More

Fig. 4 Operational limits of the RPC with various forced air injection of Q a   = 0   g / s , 3   g / s , 6   g / s , and 9   g / s More

Fig. 5 Time traces of ion signal with fuel flowrate of ( a -1): Q f   = 70 g/min; ( a -2): Q f   = 56 g/min; ( a -3) Q f = 44 g/min. Pressure signal at ( b -1): Q f   = 70 g/min; ( b -2) Q f   = 56 g/min; ( b -3) Q f   = ... More

Fig. 6 Normalized power spectrum density (PSD) of ion signal with fuel flowrates of ( a -1): Q f   = 70 g/min, ( a -2): Q f   = 56 g/min, ( a -3): Q f   = 44 g/min; pressure signal at ( b -1): Q f   = 70 g/min, ( b -2): Q f   = 56 g/... More

Fig. 7 PSD ratio based on ( a ) ion signal or ( b ) pressure signal as a function of fuel flowrate for a fixed valve frequency of 270 Hz and forced air injection of 6 g/s More

Fig. 8 RPC survival rate as a function of fuel flowrate. Sudden increase: change of forced air injection Q a from 6.0 g/s to 7.5 g/s. Sudden decrease: change of Q a from 6.0 g/s to 4.0 g/s. More

Fig. 9 Survival rate (for sudden increase and decrease) and PSD ratio as a function of fuel flowrate: ( a -1) and ( b -1) for f v  = 270 Hz, and Q a  = 6 g/s; ( a -2) and ( b -2) for f v  = 260 Hz, and Q a  = 7 g/s; ( a -3) and ( b -3) for f v  = 250 Hz, and Q a  = 8 g/s. Red lines are ... More

Fig. 1 Side view of test rig and list of major components More

Fig. 2 Photographs showing assembled flooded bearing, bearing with lower half-end seal removed to show pads and supply groove, and close up view of groove with single orifice in supply bar. Wires denote thermocouples. More

Fig. 3 Photographs showing front and back of evacuated bearing with spray bars for oil supply More

Fig. 4 Schematic view of pads and location of thermo-couples (T/C) embedded in pads More