mindurationdeep#

[tmin, tminhat, Fetchhat] = mindurationdeep(windvel, Fetch, CalcMethod, dispout)

Description#

Calculate a minimum required wind duration for wave to be fetch limited in deep 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 ‘cem’ and ‘spmdeep’ methods

For ‘cem’ and ‘spmdeep’ methods, wind velocity should be converted to duration of sustained wind by using gust factor
Fetch: Wind fetch in (m)
CalcMethod=’carter’;: Parametric wave model to be used for calculation

‘wilson’: Use method by Wislon (1965)

‘jonswap’: Use method by Hasselmann et al. (1973) known as JONSWAP

‘carter’: Use method by Carter (1982)

‘spmdeep’: Use method by Shore Protection Manual (SPM),

U.S. Army Corps of Engineers (1984) in deep water

‘cem’: Use method by Coastal Engineering Manual (CEM),

U.S. Army Corps of Engineers (2015)
dispout=’no’;: Define to display outputs or not (‘yes’: display, ‘no’: not display)

Outputs#

tmin: Minimum required wind duration for wind to be fetch limited in (second)
tminhat: Dimensionless minimum required wind duration for wind to be fetch limited: tminhat=g*tmin/U10
Fetchhat: Dimensionless Fetch: Fetchhat=g*Fetch/U10^2

Note, g=9.81: gravitational acceleration

U10: wind velocity

Examples#

windvel(:,1)=10.*rand(100,1);
Fetch(:,1)=10000.*rand(100,1);
[tmin,tminhat,Fetchhat]=mindurationdeep(windvel,Fetch,'carter','no');

windvel=10;
Fetch(:,1)=[1e3:1000:1e6];
[tmin,tminhat,Fetchhat]=mindurationdeep(windvel,Fetch,'carter','yes');

References#

Carter, D. J. T. (1982). Prediction of wave height and period for a constant wind velocity using the JONSWAP results. Ocean Engineering, 9(1), 17-33.

Department of the Army, Waterways Experiment Station, Corps of Engineers, and Coastal Engineering Research Center (1984), Shore Protection Manual, Washington, D.C., vol. 1, 4th ed., 532 pp.

Hasselmann, K.; Barnett, T. P.; Bouws, E.; Carlson, H.; Cartwright, D. E.; Enke, K.; Ewing, J. A.; Gienapp, H.; Hasselmann, D. E.; Kruseman, P.; Meerbrug, A.; Muller, P.; Olbers, D. J.; Richter, K.; Sell, W., and Walden, H., (1973). Measurements of wind-wave growth and swell decay during the Joint North Sea Wave Project (JONSWAP). Deutsche Hydrographische Zeitschrift A80(12), 95p.

U.S. Army Corps of Engineers (2015). Coastal Engineering Manual. Engineer Manual 1110-2-1100, Washington, D.C.: U.S. Army Corps of Engineers.

Wilson, B. W. (1965). Numerical prediction of ocean waves in the North Atlantic for December, 1959. Ocean Dynamics, 18(3), 114-130.

mindurationdeep

Contents