Specific impulse table

To achieve higher energy in solid proplnts the most notable advances were achieved with the addition of aluminum and beryllium to both double-base and composite proplnts. Energy in this case is commonly equated to high specific impulse. Later developments added aluminum hydride and beryllium hydride to this list. In Table 16, the specific impulse performance of proplnts using AP with various metals and hydrides is compared to those systems without these additives (Ref 43)... 

Experimentally, Flynn (Ref 73a) has tested plastisol NC composite propints containing beryllium and triaminoguanidinium hydrazinium diazide in a closed bomb and measured the high specific impulses indicated in Table 23... 

The influence of metal type on the specific impulse of propints has been described previously in this article (Table 16). The max theoretical specific impulse and density impulses (ISp x p ) for the oxidizers AN, AP and hydrazinium nitrate with 15 weight percent -fCH2)- binder have been calculated for various fuels (Ref 24). These data are in Tables 49-51. The ISp performance of nitronium perchlorate, lithium perchlorate and potassium perchlorate and metallized fuels with 4CH2>- binder are given in Table 52 (Ref 43)... 

Table 4.10 shows a comparison of the theoretical combustion properties of NC-NG-DEP and NC-NG-GAP propellants at 10 MPa. Though the molecular mass of the combustion products. Mg, remains relatively unchanged by the replacement of DEP with GAP, the adiabatic flame temperature is increased from 2557 K to 2964 K when 12.5 % DEP is replaced with 12.5 % GAP. Thus, the specific impulse is increased from 237s to 253s. The density of a propellant, p, is also an important parameter in evaluating its thermodynamic performance. The density is increased from 1530 kg m to 1590 kg m" by the replacement of DEP with GAP. Since GAP is also compatible with DEP, double-base propellants composed of four major ingredients, NG, NG, DEP, and GAP, are also formulated. 

The burning rates of a nitro-azide propellant composed of NC, NG, and GAP are shown in Fig. 6.19. For comparison, the burning rates of a double-base propellant composed of NC, NG, and DEP are shown in Fig. 6.20. The chemical compositions of both propellants are shown in Table 6.6. The adiabatic flame temperature is increased from 2560 K to 2960 K and the specific impulse is increased from 237 s to 253 s when 12.5% of DEP is replaced with the same amount of GAP. 

Table 14.4 Specific impulse (oxidizer liquid oxygen) at = 5 MPa and 8 = 100.

The molecular mass of the combustion products in the ramburner is increased by the formation of the oxidized metal particles. However, the temperature in the ramburner is also increased by the oxidation. The results of thermochemical calculations indicate that the specific impulse generated by the combustion in the ramburner is more dependent on the average combustion temperature than the average molecular mass of the products when metal particles are added. Table 15.4 shows the heats of combustion and the major oxidized products of the soHd particles used in ducted rockets. 

There are also some relationships betw specific impulse and diameters and lengths of charges, as can be seen from graph 149, p 442 and Table 95, p 443 of Ref. Relationships betw specific impulse and method of confinement are given in Table 96, p 444... 

Propellant Performance Data. Specific impulse and chamber temperature for a number of more common hypergolic propellant combinations are in the following table. Hie values are based on shifting equilibrium conditions with a chamber pressure of 1000 psia. Data are from Ref 33... 

Specific impulse, Isp, probably the most accepted measure of LP performance, was defined in Sect 1 and tabulated in Tables 1 2. The thrust, F, of a rocket is given by... 

Table II. Theoretical Specific Impulse of Selected Propellant Systems...

Table VI. Maximum Theoretical Specific Impulse Values of Heterogeneous Fuels with Nitrogen Tetroxide...

Liquid rocket propellants are subdivided into monopropellants and bipropellants. Monopropellants are liquids which burn in the absence of external oxygen. They have comparatively low energy and specific impulse and are used in small missiles which require low thrust. Hydrazine is currently the most widely used monopropellant however, hydrogen peroxide, ethylene oxide, isopropyl nitrate and nitromethane have all been considered or used as monopropellants. Information on the performance of some monopropellants is presented in Table 8.3. 

A new composition involving a solution of ADN in a mixture of glycerol and water has been presented as a new non-toxic monopropellant with a better specific impulse (Isp) than hydrazine [25], Below is a table of performance, Isp at an expansion ratio of 50 and toxicity as LD5o orally, compared with hydrazine and hydroxylammonium nitrate (HAN).2 HAN has over the past seven years emerged as a Green... 

In table n. C.I., the effect of various particle velocities, expressed as fractions of the gas velocity, on the specific impulse is illustrated for both complete thermal equilibrium and lack of thermal equilibrium. What is of practical interest is that thermal equilibrium between particle and gas is of far lesser importance than particle velocitylag. 

Table n. C. 1. - Specific Impulse Variation with Particle Lag... 

Table IV. A. 6 - Summary of Maximum Shifting Specific Impulse Data...

Table IV. C. 1 - Specific Impulse and Combustion Temperature of Several Monopropellants. (Equilibrium decomposition and expansion, Pc = 1000 psi, sea level specific impulse).

Because of the relatively low temperatures of decomposition of monopropellants, the attainment of non-equilibrium products is observed in some cases. The specific impulse and equilibrium combustion temperature of several monopropellants, are summarized in table IV. C. 1 and IV. C. 2. The non-equilibrium character of hydrazine decomposition was discussed previously in section m. A. The methyl substituted hydrazines are observed to behave in the same manner (32). These characteristics are summarized in table IV.C. 3. The non-equilibrium decomposition of the hydrazine is particularly interesting because it results in combustion temperatures and performances which are higher than those which are predicted from equilibrium considerations. 

Monopropellants possess a relatively small energy content and a specific impulse and are therefore only used in small missiles and small satellites (for correcting orbits), where no large thrust is necessary. A summary of some monopropellants can be found in Table 2.6. 

In comparison to this, the reaction of MMH with NTO generates only 6515 kj per kilogramm of a stoichiometric mixture. Table 2.8 clearly shows the influence of the average molecular mass of the combustion products (in this case the propellants) on the specific impulse. 

Table 4.13 summarizes the calculated propulsion parameters for aluminized formulations in which the Al content has been varied in order to achieve an oxygen balance that is close to zero (with respect to C02, see eq. 2). Table 4.13 contains the corresponding values for a AP /Al formulation for comparison as well. Finally, Table 4.14 shows the calculated specific impulses for equilibrium expansion for the three optimized formulations (covalent 02N—02C—C02—N02 /Al, ionic [N0]2[02C C02] /Al and AP /Al). The results of Table 4.14 are graphically summarized in Figure 4.6. 

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