def test_windage_mast_ce_position():
r"""Centre of effort position tests, with 30° of heel and 60° of heel
y position of force application at 30° should be the same as z position
of application at 60° of heel
"""
force = windage_mast_with_sail(tws=10.,
twa=45.,
boatspeed=2.,
heel_angle=30.,
trim_angle=0.,
mast_x=0.5,
mast_z_bottom=0.07,
mast_z_top=1.7,
mast_front_area=0.017,
mast_side_area=0.017)
value = ((1.7 + 0.07) / 2.) / 2.
assert value - 1e-6 <= force.py <= value + 1e-6
force = windage_mast_with_sail(tws=10.,
twa=45.,
boatspeed=2.,
heel_angle=60.,
trim_angle=0.,
mast_x=0.5,
mast_z_bottom=0.07,
mast_z_top=1.7,
mast_front_area=0.017,
mast_side_area=0.017)
assert value - 1e-6 <= force.pz <= value + 1e-6
def test_windage_mast_with_sail_port_upwind():
r"""Upwind on port tack"""
force = windage_mast_with_sail(tws=10.,
twa=-45.,
boatspeed=2.,
heel_angle=10.,
trim_angle=0.,
mast_x=0.5,
mast_z_bottom=0.07,
mast_z_top=1.7,
mast_front_area=0.017,
mast_side_area=0.017)
assert force.fx < 0
assert force.fy < 0
assert force.py < 0
force_neg_heel = windage_mast_with_sail(tws=10.,
twa=-45.,
boatspeed=2.,
heel_angle=-10.,
trim_angle=0.,
mast_x=0.5,
mast_z_bottom=0.07,
mast_z_top=1.7,
mast_front_area=0.017,
mast_side_area=0.017)
assert force_neg_heel.py > 0
def test_windage_mast_with_trim_angle():
r"""Trim angle influence tests"""
# bow up
force_stb = windage_mast_with_sail(tws=10.,
twa=45.,
boatspeed=2.,
heel_angle=30.,
trim_angle=5.,
mast_x=0.5,
mast_z_bottom=0.07,
mast_z_top=1.7,
mast_front_area=0.017,
mast_side_area=0.017)
assert force_stb.fx < 0.5
force_por = windage_mast_with_sail(tws=10.,
twa=-45.,
boatspeed=2.,
heel_angle=30.,
trim_angle=5.,
mast_x=0.5,
mast_z_bottom=0.07,
mast_z_top=1.7,
mast_front_area=0.017,
mast_side_area=0.017)
assert force_por.fx < 0.5
# bow dow
force_stb = windage_mast_with_sail(tws=10.,
twa=45.,
boatspeed=2.,
heel_angle=30.,
trim_angle=-5.,
mast_x=0.5,
mast_z_bottom=0.07,
mast_z_top=1.7,
mast_front_area=0.017,
mast_side_area=0.017)
assert force_stb.px > 0.5
force_por = windage_mast_with_sail(tws=10.,
twa=-45.,
boatspeed=2.,
heel_angle=30.,
trim_angle=-5.,
mast_x=0.5,
mast_z_bottom=0.07,
mast_z_top=1.7,
mast_front_area=0.017,
mast_side_area=0.017)
assert force_por.px > 0.5
def test_windage_mast_with_sail_port_downwind():
r"""Downwind on port tack"""
force = windage_mast_with_sail(tws=10.,
twa=-165.,
boatspeed=2.,
heel_angle=0.,
trim_angle=0.,
mast_x=0.5,
mast_z_bottom=0.07,
mast_z_top=1.7,
mast_front_area=0.017,
mast_side_area=0.017)
assert force.fx > 0
assert force.fy < 0
def test_windage_mast_with_sail_exceptions():
r"""Wrong input cases"""
with pytest.raises(ValueError):
windage_mast_with_sail(tws=10.,
twa=45.,
boatspeed=2.,
heel_angle=10.,
trim_angle=0.,
mast_x=0.5,
mast_z_bottom=-0.07,
mast_z_top=1.7,
mast_front_area=0.017,
mast_side_area=0.017)
with pytest.raises(ValueError):
windage_mast_with_sail(tws=10.,
twa=45.,
boatspeed=2.,
heel_angle=10.,
trim_angle=0.,
mast_x=0.5,
mast_z_bottom=0.07,
mast_z_top=1.7,
mast_front_area=-0.017,
mast_side_area=0.017)