scientimate.asymptlimit#

EhatAsympt, fphatAsympt, hhat = scientimate.asymptlimit(windvel, hmean, CalcMethod='karimpour')

Description#

Calculate dimensionless asymptotic limits of wind wave growth in shallow and intermediate water

Inputs#

windvel: Wind velocity in (m/s)

Wind velocity should be measured (or represents velocity) at 10 m above surface

Wind velocity should be a 10 minutes averaged wind for all methods, except for for ‘spmshallow’ methods

For ‘spmshallow’ methods, wind velocity should be converted to duration of sustained wind by using gust factor
Fetch: Wind fetch in (m)
hmean: Mean water depth along a wind fetch in (m)
CalcMethod=’karimpour’: Parametric wave model to be used for calculation

‘smb’: Use SMB method by Munk (1947), and Bretschneider (1952, 1958)

‘young’: Use method by Young and Verhagen (1996) and Young and Babanin (2006)

‘karimpour’: Use method by Karimpour et al. (2017)

Outputs#

EhatAsympt: Dimensionless asymptotic limit values for wave energy, Ehat=g^2*m0/U10^4
fphatAsympt: Dimensionless asymptotic limit values for peak wave frequency, fphat=fp*U10/9.81
hhat: Dimensionless water depth along a wind fetch: hhat=g*hmean/U10^2

Note, g=9.81: gravitational acceleration

U10: wind velocity

fp: peak wave frequency

hmean: mean depth along a wind fetch

Examples#

import scientimate as sm
import numpy as np

windvel=10*np.random.rand(100)
hmean=3*np.random.rand(100)
EhatAsympt,fphatAsympt,hhat=sm.asymptlimit(windvel,hmean,'karimpour')

References#

Bretschneider, C. L. (1952). Revised wave forecasting relationships. Coastal Engineering Proceedings, 1(2), 1.

Bretschneider, C. L. (1958). Revisions in wave forecasting: deep and shallow water. Coastal Engineering Proceedings, 1(6), 3.

Karimpour, A., Chen, Q., & Twilley, R. R. (2017). Wind Wave Behavior in Fetch and Depth Limited Estuaries. Scientific reports, 7, 40654.

Sverdrup, H. U., & Munk, W. H. (1947). Wind, sea, and swell: theory of relations for forecasting. U.S. Navy Department, Hydrographic Office, Publication No. 601, 44 pp.

Young, I. R., & Verhagen, L. A. (1996). The growth of fetch limited waves in water of finite depth. Part 1. Total energy and peak frequency. Coastal Engineering, 29(1-2), 47-78.

Young, I. R., & Babanin, A. V. (2006). The form of the asymptotic depth‐limited wind wave frequency spectrum. Journal of Geophysical Research: Oceans, 111(C6).

scientimate.asymptlimit

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