Experimental Study of Fuel Regression Rate in a HTPB/N2O Hybrid Rocket Motor

Abstract

Abstract. The performance of an HTPB/N2O hybrid motor was experimentally investigated. A hybrid motor was designed and manufactured in a laboratory with the purpose of studying the e ects of various parameters on the motor's performance, including fuel regression rate and speci c impulse. A series of tests were conducted to nd a correlation between the fuel regression rate and the oxidizer's mass ux. The e ects of chamber's pressure on the regression rate as well as other performance parameters were investigated. While the burning rate did not change dramatically, both the e ciency and ISP of the motor increased. The local fuel regression rate and the fuel port were also calculated. In addition, instantaneous regression rate was calculated using a special technique.

Design and Test of a Student Hybrid Rocket Engine with an External Carbon Fiber Composite Structure

“…As the flight fluid supply system would not be able to sustain this increased oxidizer mass flow for the complete burn time, further work would have to be carried out to achieve design performance at tolerable oxidizer mass flows. Figure 8 shows the fuel grain regression rates obtained from the four tests compared against data from the literature [8,[31][32][33]. The regression rate curves from these data follow the empirical power law [7]:ṙ = a • G n ox (18) in which the coefficients a and n were obtained through experimental data.…”

“…Only fuel grains with single circular port geometries were tested in the references presented. The determined regression rates from four HYDRA 4X tests were located between the fitting curves of [8,31,32].…”

“…These disadvantages offer a wide range of research potential; hence, various aspects of hybrid rocket engines (HRE) are addressed in the respective research. One of the main parameters under research is the experimental characterization of the fuel regression rate as investigated in [2,7,8] and how it is linked to heat transfer in the combustion chamber [9]. The regression rate also depends on other parameters like propellant choice [10,11] and the oxidizer injecting system [12,13].…”

Design and Test of a Student Hybrid Rocket Engine with an External Carbon Fiber Composite Structure

“…As the flight fluid supply system would not be able to sustain this increased oxidizer mass flow for the complete burn time, further work would have to be carried out to achieve design performance at tolerable oxidizer mass flows. Figure 8 shows the fuel grain regression rates obtained from the four tests compared against data from literature [8,[31][32][33]. The regression rate curves from these data follow the empirical power law [7] r = a · G n ox (18) in which the coefficients a and n are obtained through experimental data.…”

“…Only fuel grains with single circular port geometries were tested in the references presented. The determined regression rates from four HYDRA 4X tests are located between fitting curves of [31], [32] and [8].…”