scientimate.incidentreflectedwave#
Kr, EtaInc, EtaRef, aInc, aRef, t, f = scientimate.incidentreflectedwave(Eta1, Eta2, dx, h, fs=2, fmin=0, fmax=None, SepMethod='goda', kCalcMethod='beji', dispout='no')
Description#
Separate incident and reflected waves
Inputs#
- Eta1
Wave signal at position x1 in (m), should have same size as Eta2
- Eta2
Wave signal at position x2 in (m), should have same size as Eta1
- dx
Distance between x1 and x2 in (m), dx=x2-x1
- h
Mean water depth in (m)
- fs=2
Sampling frequency that data collected at in (Hz), if fs=1 then output is equivalent to normalized filter
- fmin=0
Minimum frequency to be considered in (Hz)
- fmax=fs/2
Maximum frequency to be considered in (Hz)
- SepMethod=’goda’
- Incident and reflected waves Separation method‘goda’: Goda and Suzuki (1977)‘ma’: Ma et al. (2010)‘frigaard’: Frigaard and Brorsen (1995)
- kCalcMethod=’beji’
- Wave number calculation method‘hunt’: Hunt (1979), ‘beji’: Beji (2013), ‘vatankhah’: Vatankhah and Aghashariatmadari (2013)‘goda’: Goda (2010), ‘exact’: calculate exact value
- dispout=’no’
Define to display outputs or not (‘yes’: display, ‘no’: not display)
Outputs#
- Kr
Reflection coefficient
- EtaInc
Incident wave (m)
- EtaRef
Reflected wave (m)
- aInc
Amplitude of incident wave (m)
- aRef
Amplitude of reflected wave (m)
- t
Time (s)
- f
Frequency (Hz)
Examples#
import scientimate as sm
import numpy as np
h=1
fs=2
dt=1/fs
duration=1024
t=np.linspace(0,duration-dt,duration*fs)
x1=1
x2=3.7
dx=x2-x1
W1=0.5*np.cos(0.412*x1-2*np.pi*0.2*t)
W2=0.5*np.cos(0.739*x1-2*np.pi*0.34*t)
EtaIncGauge1=(W1+W2)
W3=0.5*np.cos(0.412*x2-2*np.pi*0.2*t)
W4=0.5*np.cos(0.739*x2-2*np.pi*0.34*t)
EtaIncGauge2=(W3+W4)
W5=0.1*np.cos(0.412*x1+2*np.pi*0.2*t)
W6=0.1*np.cos(0.739*x1+2*np.pi*0.34*t)
EtaRefGauge1=(W5+W6)
W7=0.1*np.cos(0.412*x2+2*np.pi*0.2*t)
W8=0.1*np.cos(0.739*x2+2*np.pi*0.34*t)
EtaRefGauge2=(W7+W8)
Eta1=EtaIncGauge1+EtaRefGauge1
Eta2=EtaIncGauge2+EtaRefGauge2
Kr,EtaInc,EtaRef,aInc,aRef,t,f=sm.incidentreflectedwave(Eta1,Eta2,dx,h,fs,0,fs/2,'goda','beji','yes')
References#
Beji, S. (2013). Improved explicit approximation of linear dispersion relationship for gravity waves. Coastal Engineering, 73, 11-12.
Baldock, T. E., & Simmonds, D. J. (1999). Separation of incident and reflected waves over sloping bathymetry. Coastal Engineering, 38(3), 167-176.
Frigaard, P., Brorsen, M., 1995. A time domain method for separating incident and reflected irregular waves. Coastal Eng. 24, 205–215
Goda, Y., & Suzuki, Y. (1977). Estimation of incident and reflected waves in random wave experiments. In Coastal Engineering 1976 (pp. 828-845).
Goda, Y. (2010). Random seas and design of maritime structures. World scientific.
Hunt, J. N. (1979). Direct solution of wave dispersion equation. Journal of the Waterway Port Coastal and Ocean Division, 105(4), 457-459.
Ma, Y., Dong, G., Ma, X., & Wang, G. (2010). A new method for separation of 2D incident and reflected waves by the Morlet wavelet transform. Coastal Engineering, 57(6), 597-603.
Mansard, E. P., & Funke, E. R. (1980). The measurement of incident and reflected spectra using a least squares method. In Coastal Engineering 1980 (pp. 154-172).
Vatankhah, A. R., & Aghashariatmadari, Z. (2013). Improved explicit approximation of linear dispersion relationship for gravity waves: A discussion. Coastal engineering, 78, 21-22.