Solid-Fuel Rocket Motor Efficiency Improvement Scheme - Novel Combustion Concepts for Sustainable Energy Development - page 538

Fig. 10 Chamber with no
wedge; varied velocity
(Amano et al. 2014a , b )

(a) 0 m/s

(b) 5 m/s

(c) 10 m/s

(d) 15 m/s

(e) 20 m/s

(f) 25 m/s

(g) 30 m/s

(h) 35 m/s

(i) 40 m/s

Similarly, the Reynolds and Weber numbers vary as functions of the mean air
velocity. Figure 10 presents the

fl flow behavior observed with the absence of the

wedge obstruction.
Figure 10 displays photographs representing the fl flow behavior observed with the

ramp in the chamber obstructing the water flow. From Figs. 10 and 11 , it is clear

that water breakup begins to occur around the mean air velocity of 15 m/s. It is also
notable that both the cases are similar in breakup magnitude differing only around
the vicinity of the wedge, showing a clear enhancement of breakup behavior due to
geometric modi

fl

i shows a distinguishable increase in breakup
around the trailing edge of the wedge indicating that the wedge increases the
breakup phenomena.
Knowing that the mean air velocity of 15 m/s with constant mean water velocity
is the approximate condition for onset of the breakup, the condition for breakup can
be thought of in terms of relative mean velocity between the two

cation. Figure 11 d

-

fl fluids. It is then

convenient to use the Speci c Reynolds and Weber numbers as a criterion for

breakup. The Speci c Reynolds and Weber numbers corresponding to breakup

initiation are presented in Table 4 .
Due to the focal length and the angle of view used to capture perspective image,
distortion was observed in the photographs. The water stream boundary height was