Burning rate of HMX composite propellant

The effects of four types of binders, HTPS, HTPE, HTPA, and HTPB, on the burning rates of HMX composite propellants are shown in Fig. 7.33. The physicochemi-... 

Fig. 7.38 Burning rates of HMX composite propellants as a function of adiabatic flame temperature or hmx showing the existence of a minimum in the burning rate at about hmx (0.6).

The effects of four types of binders, HTPS, HTPE, HTPA, and HTPB on burning rate of HMX composite propellants are shown in Fig. 7-16. The physicochemical properties of these binders are shown in Table 4-7. Each propellant is composed of 80 % HMX and 20 % binder and the HMX particles are a bimodal mixture of large sized (220 pm in diameter) 70 % and small sized (20 pm in diameter) 30 %. The oxygen concentration of HTPS is the highest and that of HTPB is the lowest in the four types of binders1191. The adiabatic flame temperatures of HTPS, HTPE, HTPA, and HTPB propellants are 1940 K, 1910 K, 2040 K, and 1800 K, respectively. 

The super-rate burning rates of HMX-HTPE and HMX-HTPS propellants are shown in Figs. 7.40 and 7.41, respectively. The basic chemical compositions and... 

In order to avoid the use of lead compounds on environmental grounds, lithium fluoride (liF) has been chosen to obtain super-rate burning of nitramine composite propellants.P7281 Typical chemical compositions of HMX composite propellants-with and without liF are shown in Table 7.4. The non-catalyzed HMX propellant is used as a reference pyrolant to evaluate the effect of super-rate burning. The HMX particles are of finely divided, crystalline (3-HMX with a bimodal size distribution. Hydroxy-terminated polyether (HTPE) is used as a binder, the OH groups of which are cured with isophorone diisocyanate. The chemical properties of the HTPE binder are summarized in Table 7.5. 

The super-rate burning rates of HMX-HTPE and HMX-HTPS propellants are shown in Figs. 7-23 and 7-24, respectively. The basic chemical compositions and physicochemical properties of the noncatalyzed HMX-HTPE and HMX-HTPS propellants are the HMX-HTPE and HMX-HTPS propellants shown in Fig. 7-16, respectively. The catalysts, 2.4% PbSt and 0.4% carbon, are mixed with each noncatalyzed... 

Fig. 7.36 Dependence of burning rate on pressure and temperature sensitivity thereof for an HMX composite propellant.

Fig. 7.46 Burning rate characteristics of non-catalyzed and catalyzed HMX composite propellants.

Table 7.8 Chemical compositions of AN-(BAMO-AMMO)-HMX composite propellants with and without burning rate catalysts.

Since the energy contained within double-base propellants is limited because of the limited energies of nitrocellulose (NC) and nitroglycerin (NG), the addition of ammonium perchlorate or energetic nitramine particles such as HMX and RDX increases the combustion temperature and specific impulse. Extensive experimental studies have been carried out on the combustion characteristics of composite-modified double-base (CMDB) propellants containing AP, RDX or HMX parhclesli- l and several models have been proposed to describe the burning rates of these pro-... 

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