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- Analytical
- Goda, Y., Takayama, T. and Suzuki, Y., “Diffraction diagrams for directional random waves,” Proc. 16th International Conference Coastal Engineering. (Hamburg, 1978) pp. 628-650.
- Carr, J.H. and Stelzriede, M.E. 'Diffraction of Water Waves by Breakwaters' (Section 2.2 in particular)
- M.R., Boshek., "Reflection and Diffraction Around Breakwaters"
- Wolfram MathWorld - Cornu Spiral
- LibreTexts Physics - Cornu's Spiral
- Key equations:
- Fresnel integrals:
- Fresnel integrals:
- Diffrac-2DH
- Diffrac User-Manual (Appendix C in particular)
- Key equations:
- Helmholtz equation:
- Horizontal boundary condition equation:
- Helmholtz equation:
Tool limitations
Diffrac-2DH can only handle a maximum of eight (8) reflective boundaries. This means that the number of structure and coastline points should not result in more than eight reflective boundaries in total (excl. open boundary).
In the image below, this concept is visually shown, in the left panel, a total of 7 reflective boundaries are defined (which is ok), in the right panel, a total of 9 reflective boundaries are defined (this is too much).
For the situation in the right panel, only the analytical formation can be used (or the number of coastline points in between breakwaters reduced).
The following processes are not included in the tool: wave directional spreading, bed level changes throughout the harbor, wave reflection (in case of using the analytical method) or varying reflection values (in case of Diffrac-2DH), etc.
More information on the limitations can be found through the provided literature.
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