+#!/usr/bin/env nickle
+
+void main () {
+ real R = 22.16 * 12; /* in lbf / lbm (gas constant for ffff powder */
+ real T = 3307; /* combustion temperature for BP */
+ real d_mm; /* diameter(mm) */
+ real l_mm; /* length(mm) */
+ real f_N; /* force(N) */
+ real f_lb;
+ real A_mm²; /* area of bulkhead (mm²) */
+ real A_in²;
+ real V_mm³; /* free volume (mm³) */
+ real V_in³;
+ real M_lb; /* mass of BP in lb */
+ real M_g;
+ real P_Nmm²; /* pressure (N/mm²) */
+ real P_lbin²; /* pressure (psi) */
+
+ if (dim(argv) != 4) {
+ File::fprintf(stderr,
+ "usage: %s diameter(mm) length(mm) force(N)\n",
+ argv[0]);
+ exit(1);
+ }
+
+ d_mm = string_to_real(argv[1]);
+ l_mm = string_to_real(argv[2]);
+ f_N = string_to_real(argv[3]);
+ f_lb = f_N * 0.22480894;
+
+ A_mm² = pi * (d_mm/2) ** 2;
+ V_mm³ = A_mm² * l_mm;
+
+ A_in² = A_mm² / (25.4**2);
+ V_in³ = V_mm³ / (25.4**3);
+
+ P_Nmm² = f_N / A_mm²;
+
+ P_lbin² = P_Nmm² * 0.22480894 * (25.4 ** 2);
+
+ M_lb = (P_lbin² * V_in³) / (R * T);
+ M_g = M_lb * 453.59237;
+
+ printf ("Input parameters:\n");
+ printf (" Diameter: %.1g (mm) %.3g (in)\n",
+ d_mm, d_mm / 25.4);
+ printf (" Length: %.1g (mm) %.3g (in)\n",
+ l_mm, l_mm / 25.4);
+ printf (" Force: %.1g (N) %.3g (lb)\n",
+ f_N, f_lb);
+
+ printf ("Chamber values:\n");
+ printf (" Area: %.0f (mm²) %.3g (in²)\n",
+ A_mm², A_in²);
+ printf (" Volume: %.0f (mm³) %.3g (in³)\n",
+ V_mm³, V_in³);
+ printf (" Pressure: %.2g (lb/in²) %.5g (N/mm²)\n",
+ P_lbin², P_Nmm²);
+
+ printf ("Results:\n");
+ printf (" FFFF powder: %.3g (g)\n", M_g);
+}
+
+main();