def __init__(self,aircraft,velocity,altitude,updComponents):
self.ac = aircraft
self.refArea = self.ac.wing.area
self.aircraftDrag = AircraftDrag()
self.get_friction_drag(velocity,altitude)
if updComponents:
self.get_components_drag()
else:
self.aircraftDrag.components = aircraft.drag.components
self.aircraftDrag.update_total()
class AnalysisFW:
"""
Wrapper class for drag analysis containing friction drag and components
drag using table lookup. Aircraft main wing area is used as reference
area.
Parameters
----------
aircraft : aircraft
aircraft object
velocity : float, m/sec
velocity at which parasite drag will be calculated
altitude : float, meter
altitude at which parasite drag will be calculated
updComponents : bool
Should be true if components list was updated or at first call.
Calculation of components drag takes some time due to xls db
interface, so False option should be selected in most of the cases.
Notes
-----
Only conventional configuration provided by aircraft class can be analyzed.
For unconventional configurations use **Friction** and **PartsDrag**
separately.
Examples
--------
>>> import aircraft
>>> ac = aircraft.load('sampleInput2')
>>> V = 50.0 #m/sec
>>> h = 2000. #m
>>> drag = Analysis(ac,V,h,False)
>>> aircraftDrag = drag.get_aircraft_drag()
>>> aircraftDrag.display()
========================================
Total drag components breakdown
========================================
Name | Drag coef. |
----------------------------------------
main wing 1.0188e-02
horizontal stab. 1.8388e-03
...
antenna 1.0526e-03
----------------------------------------
TOTAL 2.4408e-02
----------------------------------------
"""
def __init__(self,aircraft,velocity,altitude,updComponents):
self.ac = aircraft
self.refArea = self.ac.wing.area
self.aircraftDrag = AircraftDrag()
self.get_friction_drag(velocity,altitude)
if updComponents:
self.get_components_drag()
else:
self.aircraftDrag.components = aircraft.drag.components
self.aircraftDrag.update_total()
def get_friction_drag(self,velocity,altitude):
"""
Calculates friction drag of an aircraft using Friction class
at given velocity and altitude.
Returns
-------
items : DragList
list of the drag components with drag coefficients used for
friction drag calculation (Body, wing, empennage)
"""
frictionDrag = Friction(self.refArea)
frictionDrag.set_flight_conditions(velocity,altitude)
items = DragList()
items.add_item( frictionDrag.analyze_wing(self.ac.wing,'main wing') )
self.aircraftDrag.friction = items
return items
def get_components_drag(self):
"""
Calculates components drag using PartsDrag class methods using table
lookup methods.
Returns
-------
items : DragList
list of the drag components with drag coefficients obtained by
PartsDrag (langing gear, antenna etc.)
"""
drag = PartsDrag(self.refArea)
items = drag.get_items_drag(self.ac.drag.components)
self.aircraftDrag.components = items
return items
def get_aircraft_drag(self):
"""
Returns list of full drag components.
"""
self.aircraftDrag.update_total()
return self.aircraftDrag
