(2) The value of *h, *is of the order of 25 to 30 ft-lb/in.2 for aircraft hose. The value of β is approximately 0.2 to

0.3.

(3) For example, the M3A1 thruster is designed to bypass gas into a 3/16-inch (inside diameter) A hose at the

end of its stroke. The parameters from chapter 6 are:

Thruster: *P*f = 5,700 psi

Hose:

(4) These values are substituted in equation (49) using *h*t = 26 ft-lb/in.2 and β = 0.3. The curve which results is

given in figure 51 as hose pressure, *P*t, versus hose length, Lt, and it follows the experimental curve

closely enough to confirm the choice of the various parameters.

(1) An estimate of the locked-shut pressure in a thruster can be obtained from the equation of state by making

a few assumptions:

(16)

In terms of charge weight, *C, *and propellant impetus, *F,*

Where:

(2) The factor 0.54 is estimated as follows:

reduced by about 40 percent due to dissipation of heat to the walls of the device.

† The additional 0.1 in.3 is for end block and gas volume, etc.

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