Fix beta. Amendment to precice#379.

Author: BenjaminRodenberg

partitioned-heat-conduction/fenics/heat.py

@@ -67,7 +67,7 @@ def determine_gradient(V_g, u, flux):
 error_tol = args.error_tol
 
 alpha = 3  # parameter alpha
-beta = 1.3  # parameter beta
+beta = 1.2  # parameter beta
 
 if args.dirichlet and not args.neumann:
     problem = ProblemType.DIRICHLET