Study of Gas-Centered Coaxial Injector Using Jet …
375
due to which spray becomes less dense and drop size increases. From Fig. 6a–f, as
MFR increases cone angle decreases slightly. This is mainly due to the reduction of
flow rate of GN2.
5 Conclusion
The major findings achieved through the experimental cold flow atomization study
of coaxial injectors are, in the mixing of propellants the Momentum flux ratio is
a key parameter. When the MFR (liquid to gas) increases, the drop size increases
and degree of atomization decreases. In all injectors, increasing trend of drop size
is observed, when the downstream position increases. Up to the initial three points,
drop size are nearly identical and last two points show the wide variation due to the
reduction of velocity of gas and the effect of coalescence. As MFR increases spray
cone angle decreases and vice versa. The spray cone angle is higher at low MFR due
to the presence of high mass flow rate of GN2. Weber number increases, drop size
decreases at all downstream positions. At high Weber number, the velocity of the gas
and the relative velocity were high. Therefore, atomization is better and drop size is
lower. Increase in Weber number means the disruptive force increases and the liquid
jet disintegrates into drops easily.
References
1. Lefebrve AH (1989) A text book of atomization and sprays. Taylor & Francis Publication
2. Mashayek A, Ashgriz N (1985) A text book of atomization and sprays. Springer Publication
3. Crabb D et al (1981) A round jet in a cross flow. The American Society of Mechanical
Engineering 142/103
4. Yoon HJ et al (2011) Correlations for penetration height of single and double liquid jets in
cross flow under high-temperature conditions. Atom Sprays 21(8): 673–686
5. Im J-H et al (2010) Comparative study of spray characteristics of gas centered and liquid
centered swirl co axial injectors. J Propul Power 26(6)
6. Zheng Y, Marshall A (2011) Characterization of the initial spray from low webber number jet
in cross flow. Atom Sprays 21(7):575–589
7. Andreopoulos J, Rodi W (1984) Experimental investigation of jet in a cross flow. J Fluid Mech
133:93–127
8. Wu P-K et al (1997) Breakup process of liquid jet in subsonic cross flows. Journal of propulsion
and power 13(1)
9. Birouk M et al (2011) Effect of nozzle geometry on break up length and trajectory of liquid jet
in subsonic cross flow. Atom Sprays 21(10):847–865
10. Song J et al (2011) Effect of orifice internal flow on liquid jet in subsonic cross flow. J Propul
Power 27(3)
11. Pai MG et al (2009) Role of webber number in primary break up of turbulent liquid jet in cross
flow. Annual research briefs of center for turbulent research
12. Kim JG et al (2013) Study on spray patterns of gas entered swirl coaxial injector in high
pressure conditions. Aerospace Sci Technol 27:171–178
375
due to which spray becomes less dense and drop size increases. From Fig. 6a–f, as
MFR increases cone angle decreases slightly. This is mainly due to the reduction of
flow rate of GN2.
5 Conclusion
The major findings achieved through the experimental cold flow atomization study
of coaxial injectors are, in the mixing of propellants the Momentum flux ratio is
a key parameter. When the MFR (liquid to gas) increases, the drop size increases
and degree of atomization decreases. In all injectors, increasing trend of drop size
is observed, when the downstream position increases. Up to the initial three points,
drop size are nearly identical and last two points show the wide variation due to the
reduction of velocity of gas and the effect of coalescence. As MFR increases spray
cone angle decreases and vice versa. The spray cone angle is higher at low MFR due
to the presence of high mass flow rate of GN2. Weber number increases, drop size
decreases at all downstream positions. At high Weber number, the velocity of the gas
and the relative velocity were high. Therefore, atomization is better and drop size is
lower. Increase in Weber number means the disruptive force increases and the liquid
jet disintegrates into drops easily.
References
1. Lefebrve AH (1989) A text book of atomization and sprays. Taylor & Francis Publication
2. Mashayek A, Ashgriz N (1985) A text book of atomization and sprays. Springer Publication
3. Crabb D et al (1981) A round jet in a cross flow. The American Society of Mechanical
Engineering 142/103
4. Yoon HJ et al (2011) Correlations for penetration height of single and double liquid jets in
cross flow under high-temperature conditions. Atom Sprays 21(8): 673–686
5. Im J-H et al (2010) Comparative study of spray characteristics of gas centered and liquid
centered swirl co axial injectors. J Propul Power 26(6)
6. Zheng Y, Marshall A (2011) Characterization of the initial spray from low webber number jet
in cross flow. Atom Sprays 21(7):575–589
7. Andreopoulos J, Rodi W (1984) Experimental investigation of jet in a cross flow. J Fluid Mech
133:93–127
8. Wu P-K et al (1997) Breakup process of liquid jet in subsonic cross flows. Journal of propulsion
and power 13(1)
9. Birouk M et al (2011) Effect of nozzle geometry on break up length and trajectory of liquid jet
in subsonic cross flow. Atom Sprays 21(10):847–865
10. Song J et al (2011) Effect of orifice internal flow on liquid jet in subsonic cross flow. J Propul
Power 27(3)
11. Pai MG et al (2009) Role of webber number in primary break up of turbulent liquid jet in cross
flow. Annual research briefs of center for turbulent research
12. Kim JG et al (2013) Study on spray patterns of gas entered swirl coaxial injector in high
pressure conditions. Aerospace Sci Technol 27:171–178