use flash to solve LL

ipqa-research · Jan 29, 2025 · 0697809 · 0697809
1 parent cf1444a
commit 0697809
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Showing 2 changed files with 15 additions and 6 deletions.
diff --git a/python/yaeos/core.py b/python/yaeos/core.py
@@ -1233,8 +1233,7 @@ def saturation_pressure(
         }
 
     def saturation_temperature(
-        self, z, pressure: float, kind: str = "bubble", t0: float = 0,
-        y0=None
+        self, z, pressure: float, kind: str = "bubble", t0: float = 0, y0=None
     ) -> dict:
         """Saturation temperature at specified pressure.
 

diff --git a/python/yaeos/fitting/solvers.py b/python/yaeos/fitting/solvers.py
@@ -26,11 +26,21 @@ def solve_pt(model, p, t):
     """Solve a point at a given P and T."""
     from scipy.optimize import root
 
-    x10, y10 = find_init_binary_ll(model, p, t)
+    try:
+        x10, y10 = find_init_binary_ll(model, p, t)
+    except ValueError:
+        x10, y10 = 0.1, 0.9
 
-    x0 = [x10, y10]
-    sol = root(binary_isofugacity_x1y1pt, x0, (p, t, model))
-    x1, y1 = sol.x
+    mean = (x10 + y10) / 2
+
+    z = [mean, 1 - mean]
+    y0 = np.array([y10, 1 - y10])
+    x0 = np.array([x10, 1 - x10])
+
+    flash = model.flash_pt(z, pressure=p, temperature=t, k0=y0 / x0)
+
+    x1 = flash["x"][0]
+    y1 = flash["y"][0]
 
     return x1, y1