def CalcTorqueCoef(self):
self.rpm = toRPM(self.angVel)
self.rps = self.rpm / 60
self.J = self.vInf / (self.rps * self.diameter / 12)
a = fit.poly_func(self.powerCoefs.T, self.rpm)
if (a[-1] > 0): #Quadratic coefficient should always be non-positive
a[-1] = 0
self.Cl = fit.poly_func(a, self.J) / 2 * np.pi
def CalcThrustCoef(self):
self.rpm = toRPM(self.angVel)
self.rps = self.rpm/60
if abs(self.rps)<1e-10:
self.J = 10000 #To prevent errors. Since angular velocity is 0, actual value w_ill also be 0.
else:
self.J = self.v_inf/(self.rps*self.diameter/12)
a = fit.poly_func(self.thrustCoefs.T, self.rpm)
if(a[-1]>0):#Quadratic coefficient should always be non-positive
a[-1] = 0
self.Ct = fit.poly_func(a, self.J)
def __init__(self, name, dia, pitch, coefs):
self.name = name
self.diameter = float(dia) * 0.0254
self.pitch = float(pitch) * 0.0254
self.thrustFitOrder = int(coefs[0])
self.fitOfThrustFitOrder = int(coefs[1])
self.powerFitOrder = int(coefs[2])
self.fitOfPowerFitOrder = int(coefs[3])
numThrustCoefs = (self.thrustFitOrder +
1) * (self.fitOfThrustFitOrder + 1)
self.thrustCoefs = coefs[4:numThrustCoefs + 4].reshape(
(self.thrustFitOrder + 1,
self.fitOfThrustFitOrder + 1)).astype(np.float)
self.powerCoefs = coefs[numThrustCoefs + 4:].reshape(
(self.powerFitOrder + 1,
self.fitOfPowerFitOrder + 1)).astype(np.float)
#These parameters will be set by later functions
self.vInf = 0.0
self.angVel = 0.0
#Plot thrust and torque coefficients
rpms = np.linspace(0, 6000, 10)
Js = np.linspace(0, 1.4, 10)
fig = plt.figure(figsize=plt.figaspect(1.))
ax = fig.add_subplot(1, 2, 1, projection='3d')
for rpm in rpms:
a = fit.poly_func(self.thrustCoefs.T, rpm)
thrust = fit.poly_func(a, Js)
rpmForPlot = np.full(len(thrust), rpm)
ax.plot(Js, rpmForPlot, thrust, 'r-')
ax.set_title("Predicted Thrust")
ax.set_xlabel("Advance Ratio")
ax.set_ylabel("RPM")
ax.set_zlabel("Thrust Coefficient")
ax = fig.add_subplot(1, 2, 2, projection='3d')
for rpm in rpms:
a = fit.poly_func(self.powerCoefs.T, rpm)
power = fit.poly_func(a, Js)
rpmForPlot = np.full(len(power), rpm)
ax.plot(Js, rpmForPlot, power, 'r-')
ax.set_title("Predicted Power")
ax.set_xlabel("Advance Ratio")
ax.set_ylabel("RPM")
ax.set_zlabel("Power Coefficient")
plt.show()
def PlotCoefs(self):
#Plot thrust and torque coefficients
rpms = np.linspace(0, 6000, 10)
Js = np.linspace(0, 1.4, 10)
fig = plt.figure(figsize=plt.figaspect(1.))
fig.suptitle(self.name)
ax = fig.add_subplot(1, 2, 1, projection='3d')
for rpm in rpms:
a = fit.poly_func(self.thrustCoefs.T, rpm)
if (a[-1] >
0): #Quadratic coefficient should always be non-positive
a[-1] = 0
thrust = fit.poly_func(a, Js)
rpmForPlot = np.full(len(thrust), rpm)
ax.plot(Js, rpmForPlot, thrust, 'r-')
ax.set_title("Predicted Thrust")
ax.set_xlabel("Advance Ratio")
ax.set_ylabel("RPM")
ax.set_zlabel("Thrust Coefficient")
ax = fig.add_subplot(1, 2, 2, projection='3d')
for rpm in rpms:
a = fit.poly_func(self.powerCoefs.T, rpm)
if (a[-1] >
0): #Quadratic coefficient should always be non-positive
a[-1] = 0
power = fit.poly_func(a, Js)
rpmForPlot = np.full(len(power), rpm)
ax.plot(Js, rpmForPlot, power, 'r-')
ax.set_title("Predicted Power")
ax.set_xlabel("Advance Ratio")
ax.set_ylabel("RPM")
ax.set_zlabel("Power Coefficient")
plt.show()
def CalcThrustCoef(self):
self.rpm = toRPM(self.angVel)
self.J = self.vInf / (self.rpm * self.diameter)
a = fit.poly_func(self.thrustCoefs.T, self.rpm)
self.Ct = fit.poly_func(a, self.J)
def CalcTorqueCoef(self):
self.rpm = toRPM(self.angVel)
self.J = self.vInf / (self.rpm * self.diameter)
a = fit.poly_func(self.powerCoefs.T, self.rpm)
self.Cl = fit.poly_func(a, self.J) / 2 * np.pi
plt.subplot(1, 2, 2)
plt.plot(staticArray[:, 0], staticArray[:, 2])
plt.xlabel("RPM")
plt.ylabel("Power Coef")
plt.suptitle("Static data for " + propFolder)
plt.show()
#Fit dynamic data
thrustFitArray = np.zeros((rpmCount, thrustFitOrder + 1))
powerFitArray = np.zeros((rpmCount, powerFitOrder + 1))
propCoefDict = {}
for rpmIndex in range(rpmCount):
staticThrust = fit.poly_func(staticThrustFit, rpms[rpmIndex])
staticPower = fit.poly_func(staticPowerFit, rpms[rpmIndex])
advRatioInit = np.append(0, coefArray[rpmIndex, :, 0])
thrustInit = np.append(staticThrust, coefArray[rpmIndex, :, 2])
powerInit = np.append(staticPower, coefArray[rpmIndex, :, 3])
good = np.where((thrustInit != 0.) & (powerInit != 0.))
advRatio = advRatioInit[good]
thrust = thrustInit[good]
power = powerInit[good]
propCoefDict[rpms[rpmIndex]] = np.asarray(
[advRatio, np.zeros(len(advRatio)), thrust, power]).T
