move wingskin constraints to global level

convexengineering · Oct 12, 2017 · b095621 · b095621
1 parent fd2626b
commit b095621
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Showing 2 changed files with 10 additions and 12 deletions.
diff --git a/gpkitmodels/GP/aircraft/wing/wing.py b/gpkitmodels/GP/aircraft/wing/wing.py
@@ -21,8 +21,8 @@ def setup(self, N=5, lam=0.5, spar="CapSpar", hollow=False):
 
         self.surf = AeroSurf(N=N, lam=lam, spar=spar, hollow=hollow)
         self.spar = CapSpar(N)
-        self.wingskin = WingSkin(self.surf["S"], self.surf["c_{root}"], self.surf["b"])
-        self.components = [self.spar, self.wingskin]
+        self.skin = WingSkin()
+        self.components = [self.spar, self.skin]
 
         if not hollow:
             self.winginterior = WingInterior(self.surf["c_{ave}"], self.surf["b"], N)
@@ -34,6 +34,8 @@ def setup(self, N=5, lam=0.5, spar="CapSpar", hollow=False):
             self.spar["w"] <= self.spar["w_{lim}"]*self.surf["c_{ave}"],
             self.surf["c_{ave}"]*self.surf["\\tau"] >= (
                 self.spar["h_{in}"] + 2*self.spar["t"]),
+            self.skin["W"] >= (self.skin["\\rho_{CFRP}"]*self.surf["S"]*2
+                               * self.skin["t"]*self.skin["g"]),
             ]
 
         self.flight_model = WingAero
@@ -76,7 +78,7 @@ class WingLoading(Model):
     "wing loading cases"
     def setup(self, wing, Wcent, Wwing=None, V=None, CL=None):
 
-        loading = [wing.wingskin.loading()]
+        loading = [wing.skin.loading(wing)]
         loading.append(wing.spar.loading(wing, Wcent))
         if Wwing:
             loading.append(wing.spar.gustloading(wing, Wcent, Wwing, V, CL))

diff --git a/gpkitmodels/GP/aircraft/wing/wing_skin.py b/gpkitmodels/GP/aircraft/wing/wing_skin.py
@@ -3,7 +3,7 @@
 
 class WingSkin(Model):
     "wing skin model"
-    def setup(self, S, croot, b):
+    def setup(self):
 
         rhocfrp = Variable("\\rho_{CFRP}", 1.6, "g/cm^3", "density of CFRP")
         W = Variable("W", "lbf", "wing skin weight")
@@ -13,15 +13,11 @@ def setup(self, S, croot, b):
         Jtbar = Variable("\\bar{J/t}", 0.01114, "1/mm",
                          "torsional moment of inertia")
 
-        constraints = [W >= rhocfrp*S*2*t*g,
-                       t >= tmin,
-                       b == b,
-                       croot == croot]
+        constraints = [t >= tmin]
 
-        return constraints
+        self.loading = WingSkinL
 
-    def loading(self):
-        return WingSkinL(self)
+        return constraints
 
 class WingSkinL(Model):
     "wing skin loading model for torsional loads in skin"
@@ -35,6 +31,6 @@ def setup(self, static):
 
         constraints = [
             taucfrp >= (1/static["\\bar{J/t}"]/(static["c_{root}"])**2
-                        / static["t"]*Cmw*static["S"]*rhosl*Vne**2)]
+                        / static.skin["t"]*Cmw*static["S"]*rhosl*Vne**2)]
 
         return constraints