Any public data about Isp of Amraam solid fuel？

[strathlou]

Is there any public data about Isp of Amraam solid fuel？I know 260s is too high, but 235s might be too low, exchange 10% Isp for white smoke?

[nighthawk2174]

You can read up what IASGATG wrote in his paper, and what i've found so far:

^ Chemistry Of High Energy Materials 2nd Edition

 

 

 

 

Something else of note which I found in the same book, Chemistry of High Energy Materials, I wonder if the more modern AMRAAM's the C7 and/or D can owe part of their increase in range over the C5 due to the use of other fuel mixes? Something that is quite interesting to me.

[Маэстро]

Performance data for most of modern missile rocket motors are classified. But I believe we can make good estimates. Isp of 260-265sec is actually too high for composite HTPB/AP propellants. Such a values of Isp can provide metallized propellants in test conditions. Unfortunately, all they are smoky(Al2O3 exhaust). Below are charts for HTBP based composite propellants from the Sutton's book. As you can see the theoretical max Isp for HTPB/AP is about 250sec. However, such values can not be achieved due to technological limits, also propellant should include a few percents of other chemical compounds to provide required mechanical/physical properties of charge. Moreover, Isp of real motor will be less then theoretical because of different losses(about 4%).

 

As estimation of Isp for HTPB/AP propellant rocket motor known data for HARM motor can be used. Total impulse 64 000 lb-sec (29 030 kg-sec), fuel wieght 127kg.

So, average Isp = 29030/127 = 228.6 sec