Experimental study of linear burning rates of liquid isopropyl nitrate

A high-pressure burner with continuous feed is used to investigate linear burning rates of liquid isopropyl nitrate as a function of chamber pressure. The present study investigates the pressure dependence in a subset of the low-pressure region, ranging from 5.5 MPa to 8 MPa, which has been previously neglected. The new measured data fall between the extrapolated fits from prior measures at lower and higher pressures. A fit to Saint Robert's Law is found for 5.5 MPa to 7.05 MPa with a = 0.351 and n=1.03 with a slope break indicating a combustion regime shift identified around 7.1 MPa. To the best of our knowledge, these data represent the first measured burn rates of a liquid nitrate ester in a continuous feed strand burner. A numerical simulation with a detailed kinetic model reveals the elementary reactions that are most responsible for distinct heat release zones. The potential influence of multi-phase interactions is noted.