• 한국연소학회:학술대회논문집
• /
• 2005.10a
• /
• pp.287-293
• /
• 2005

Most of all combustion system has combustion instability. It is a serious problem in combustion system. Unstable injection is one of the source of combustion instability. The experimental investigation of spray characteristics for simplex swirl injector were conducted experimentally. Two kerosene based fuels were chosen as the atomizing fluid. As the major operating parameters, fuel temperature and injection pressure were chosen, and varied in the range from 253 K to 293 K and from 0.2 MPa to 1.0 MPa, respectively. Direct spray images and mean diameter were measured for the various combination of operating parameters in the flow field. The results of present study show that the injection pressure and spray cone angle are fluctuated at specific conditions while it is continuous steady injection. As the fuel temperature changes continuously, spray cone angle varies discontinuously through the region of injection instability.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2012.05a
• /
• pp.70-75
• /
• 2012

In this paper, the regression rate of the End-Burning Hybrid Rocket with variation of swirl intensity was investigated experimentally with the variation of fuel diameter, injector shape and angle. When fuel grain diameter is large, fuel mass flow rate increases. And the injector diameter increase, fuel regression rate decrease. The impinging effect of oxidizer flow on fuel surface for fuel combustion efficiency is stronger than swril effect in this End-burning propulsion system. The relation between the regression rate, oxidizer mass flux and swirl intensity was obtained.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• v.y2005m4
• /
• pp.66-71
• /
• 2005

In this study the regression rate of hybrid rocket fuel has been investigated by two methods. First method is to use swirl injectors for enhancement of regression rate. And second method is the modification of the helical grain deriving improvement of combustion area and generating swirl flow. Tests have been done with PMMA and gaseous oxygen. In this paper the incline angle of the helical grain was varied to find the optimal condition to obtain the max regression rate for a given operational condition.