Fix turbine

tests/test_wind_turbine.py

@@ -97,3 +97,14 @@ def test_wrongly_defined_to_group_method(self):
                            match="The 'number' and the 'total_capacity' "
                                  "parameter are mutually exclusive."):
             e_t_1.to_group(5, 3000)
+
+    def test_create_unphysical_turbine(self):
+        err_msg = "1/2rotor_diameter cannot be greater than hub_height"
+        char = {
+           'hub_height': 80,
+           'rotor_diameter': 160,
+           'turbine_type': 'DUMMY 3',
+           'path': self.source
+        }
+        with pytest.raises(ValueError, match=err_msg):
+            WindTurbine(**char)

windpowerlib/wind_turbine.py

@@ -163,6 +163,11 @@ def __init__(self, hub_height, nominal_power=None, path='oedb',
                 if self.rotor_diameter is None and turbine_data is not None:
                     self.rotor_diameter = float(turbine_data['rotor_diameter'])
 
+        if self.rotor_diameter:
+            if self.hub_height <= 0.5*self.rotor_diameter:
+                msg = "1/2rotor_diameter cannot be greater than hub_height"
+                raise ValueError(msg)
+
         if self.power_curve is None and self.power_coefficient_curve is None:
             msg = ("The WindTurbine has been initialised without a power curve"
                    " and without a power coefficient curve.\nYou will not be"