Appendix A A-4 A.3.7 Phase II: Metered Discharge of Halon 1301.
A.3.7.1 The metered discharge of Halon 1301 starts at the beginning of Phase II. The example in Figure A-1 of this AC shows that the metering rate is set to release Halon 1301 into the cargo compartment at a rate that is slightly greater than the rate Halon 1301 is lost through cargo compartment leakage.
A.3.7.2 The governing equation for metering during Phase II is the following:
∁(𝑡) = [∁(0) − {𝑅𝑆𝐸 }] 𝑒−𝐸𝑡𝑉 + {𝑅𝑆𝐸 } Note: “C(0)” is the concentration of Halon 1301 at the end of Phase I, and “t” is the time elapsed since the end of Phase I.
A.3.8 Phase III: Exponential “Decay” of Halon 1301.
The beginning of Phase III marks the end of Halon 1301 metering. As in Phase I, since no more Halon 1301 is introduced into the cargo compartment, the concentration of Halon 1301 undergoes an exponential “decay” versus time. The governing equation for exponential “decay” during Phase III is the same as during Phase I with one exception:
“C(0)” is the concentration of Halon 1301 at the end of Phase II, and “t” is the time since the end of Phase II.
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