Combustion characteristics of ammonium perchlorate base solid propellant in strand burner / Mohammad Hafizi Jamaluddin

Faculty of Mechanical and Automotive Engineering Technology

Thesis (Master of Engineering (Mechanical)) -- Universiti Malaysia Pahang – 2020

Includes bibliographical references

Substantial research work has been performed on the composite solid propellant over the past few decades to bring much progress. Yet, many of the fundamental studies, including the processes, are still unclear. One of the critical factors that play a vital role in solid propellant rocket performance is its burning rate. Strand burner was one of the established methods used to measure the linear burning rate of solid propellant at elevated pressure. The purpose of this research is to investigate the burning rate of ammonium perchlorate to develop strand burner. The study also compares the burning rate of ammonium perchlorate at different composition ratio. Then, the performance of strand burner and the combustion characteristics of ammonium perchlorate inside strand burner is studied. The strand burner assembly, ignition system, piping system and data collection system are modified and improved from the previous model done by another researcher. Solidwork was used to improve the current design of the strand burner and simulation using Solidwork Simulation. The improvement including an additional hole at the strand burner end cap and modifying electronic timer which connected to Data Acquisition (DAQ) to get more accurate data. The research using by four formulations which perpetuate 85% of total solid loading and distinguished to the oxidizer to fuel mixture ratio to 1.50, 1.94, 2.84 and 4.00 by comparing the mass of ammonium perchlorate as an oxidizer to the mass of fuel consist aluminium as metal fuel and binder, HTPB. Maximum stress distributed is 744.479MPa (7,444.79 bar) while the minimum stress is 0.457726 MPa (4.57726 bar). The stress is rich at the centre of the strand burner, where the highest-pressure flow distributed. The stress also rich at the strand burner end caps because the gas is flowing through a small area hole. The results show that all the system applied to the strand burner are sustainable to test the strand burner until 470 psi (32 bar). Also, the results show that the value of the characteristics of pressure exponent n lies on the range between 0.461 until 0.886 where the empirical constant, a varied in the range of 3.010 to 18.176 for all formulations that tested at the test pressure range of 1 bar to 7 bar. The strand burner facility develops had succeeded to obtain burning rate data and normal burning characteristics of AP60, AP66, AP74 and AP80 at a pressure range of 1 bar to 7 bar. The improved strand burner provides more accurate combustion data, and experimental work becomes safer than the previous model.