use aerosurf to make vertical tail

gpkitmodels/GP/aircraft/tail/empennage.py

@@ -12,21 +12,20 @@ def setup(self):
         W = Variable("W", "lbf", "empennage weight")
 
         self.htail = HorizontalTail()
-        self.verticaltail = VerticalTail()
+        self.vtail = VerticalTail()
         self.tailboom = TailBoom()
-        self.components = [self.htail, self.verticaltail,
-                           self.tailboom]
+        self.components = [self.htail, self.vtail, self.tailboom]
 
         state = TailBoomState()
         loading = [self.tailboom.horizontalbending(self.htail, state),
-                   self.tailboom.verticalbending(self.verticaltail, state),
-                   self.tailboom.verticaltorsion(self.verticaltail, state)]
+                   self.tailboom.verticalbending(self.vtail, state),
+                   self.tailboom.verticaltorsion(self.vtail, state)]
 
         constraints = [
-            W/mfac >= (self.htail.topvar("W") + self.verticaltail["W"]
+            W/mfac >= (self.htail.topvar("W") + self.vtail.topvar("W")
                        + self.tailboom["W"]),
             self.tailboom["l"] >= self.htail["l_h"],
-            self.tailboom["l"] >= self.verticaltail["l_v"],
+            self.tailboom["l"] >= self.vtail["l_v"],
             ]
 
         return self.components, constraints, loading

gpkitmodels/GP/aircraft/tail/horizontal_tail.py

@@ -20,7 +20,7 @@ def setup(self, N=3, lam=0.8):
         mfac = Variable("m_{fac}", 1.1, "-", "horizontal tail margin factor")
 
         cb, eta, deta, cbarmac = c_bar(lam, N)
-        subdict = {"\\lambda": lam, "\\bar{c}": cb, "\\eta": eta,
+        subdict = {"\\lambda": lam, "\\bar{c}": cb, "\\eta": eta, "AR": 5.0,
                    "\\bar{c}_{ave}": (cb[1:]+cb[:-1])/2, "\\tau": 0.08,
                    "\\bar{c}_{MAC}": cbarmac, "d\\eta": deta, "C_{L_{max}}": 1.5}
 

gpkitmodels/GP/aircraft/tail/vertical_tail.py

@@ -1,42 +1,48 @@
 " vertical tail "
+import numpy as np
 from gpkit import Model, Variable
 from tail_aero import TailAero
+from gpkitmodels.GP.aircraft.wing.wing import AeroSurf
+from gpkitmodels.GP.aircraft.wing.constant_taper_chord import c_bar
+from gpkitmodels.GP.aircraft.wing.wing_interior import WingInterior
+from gpkitmodels.GP.aircraft.wing.wing_skin import WingSkin
 
 class VerticalTail(Model):
     "vertical tail model"
-    def setup(self, lam=0.7):
-
-        W = Variable("W", "lbf", "one vertical tail weight")
-        Sv = Variable("S", "ft**2", "total vertical tail surface area")
-        Vv = Variable("V_v", 0.05, "-", "vertical tail volume coefficient")
-        ARv = Variable("AR_v", "-", "vertical tail aspect ratio")
-        bv = Variable("b", "ft", "one vertical tail span")
-        rhofoam = Variable("\\rho_{foam}", 1.5, "lbf/ft^3",
-                           "Density of formular 250")
-        rhoskin = Variable("\\rho_{skin}", 0.049, "g/cm**2",
-                           "vertical tail skin density")
-        Abar = Variable("\\bar{A}_{NACA0008}", 0.0548, "-",
-                        "cross sectional area of NACA 0008")
-        g = Variable("g", 9.81, "m/s^2", "Gravitational acceleration")
-        lv = Variable("l_v", "ft", "horizontal tail moment arm")
-        ctv = Variable("c_{t_v}", "ft", "vertical tail tip chord")
-        crv = Variable("c_{r_v}", "ft", "vertical tail root chord")
-        lamv = Variable("\\lambda", lam, "-", "vertical tail taper ratio")
-        lamvfac = Variable("\\lambda_v/(\\lambda_v+1)", lam/(lam+1), "-",
-                           "vertical tail taper ratio factor")
-        CLvtmax = Variable("C_{L_{max}}", 1.1, "-",
-                           "maximum CL of vertical tail")
+    def setup(self, N=3, lam=0.8):
+
+        Vv = Variable("V_v", "-", "vertical tail volume coefficient")
+        W = Variable("W", "lbf", "vertical tail weight")
+        lv = Variable("l_v", "ft", "vertical tail moment arm")
         mfac = Variable("m_{fac}", 1.1, "-", "vertical tail margin factor")
-        tau = Variable("\\tau", 0.08, "-", "vertical tail thickness ratio")
 
-        constraints = [bv**2 == ARv*Sv,
-                       W/mfac >= rhofoam*Sv**2/bv*Abar + g*rhoskin*Sv,
-                       ctv == 2*Sv/bv*lamvfac,
-                       crv == ctv/lam,
-                       lamv == lamv
-                      ]
+        cb, eta, deta, cbarmac = c_bar(lam, N)
+        subdict = {"\\lambda": lam, "\\bar{c}": cb, "\\eta": eta,
+                   "\\bar{c}_{ave}": (cb[1:]+cb[:-1])/2, "\\tau": 0.08,
+                   "\\bar{c}_{MAC}": cbarmac, "d\\eta": deta, "C_{L_{max}}": 1.5}
+
+        self.surf = AeroSurf(N=N)
+        self.surf.substitutions.update(subdict)
+
+        self.skin = WingSkin()
+        self.skin.substitutions.update({"\\rho_{CFRP}": 0.049})
+        self.foam = WingInterior()
+        self.foam.substitutions.update({"\\bar{A}_{jh01}": 0.0548})
+        self.foam.substitutions.update({"\\rho_{foam}": 0.024})
+
+        self.components = [self.skin, self.foam]
+
+        constraints = [
+            W/mfac >= sum([c["W"] for c in self.components]),
+            self.skin["W"] >= (self.skin["\\rho_{CFRP}"]*self.surf["S"]*2
+                               * self.skin["t"]*self.skin["g"]),
+            self.foam["W"] >= 2*(
+                self.foam["g"]*self.foam["\\rho_{foam}"]
+                *self.foam["\\bar{A}_{jh01}"]*self.surf["c_{ave}"]**2
+                * (self.surf["b"]/2)*self.surf["d\\eta"]).sum()
+            ]
 
-        return constraints
+        return constraints, self.surf, self.components
 
     def flight_model(self, state):
         return TailAero(self, state)