# cgWindWaves > Wave Characteristic Computation from Wind Data for Coastal and Offshore Engineering Canonical: https://www.ramcadds.com/products/cgwindwaves Source: RAM CADDSYS product catalog — https://www.ramcadds.com/products Last verified: 2026-07-18 Categories: infrastructure-geotechnical cgWindWaves is a wind-generated wave analysis software that computes wave characteristics from wind data for coastal and offshore engineering projects. It calculates significant wave height, peak period, and wave spectra from wind speed, fetch, and duration data, providing essential design wave parameters for marine infrastructure and coastal protection design. cgWindWaves is a wind-generated wave analysis program from RUNET that forecasts design wave conditions in restricted-fetch waters — harbours, marinas, lakes and reservoirs. From a water region, wind direction and velocity it computes significant wave height (Hs), significant wave period (Ts) and the wave spectrum S(f) using the semi-empirical SMB relations, outputting Pierson-Moskowitz and JONSWAP spectra. RAM CADDSYS supplies and supports it in India. cgWindWaves by RUNET (RUNET Software / RUNET Norway AS) is a specialized desktop tool for forecasting wind-generated waves in restricted-fetch water regions. From a defined water region, the mean wind direction, and the wind velocity, it computes the significant wave height (Hs), the significant wave period (Ts), and the wave spectrum S(f). It applies the semi-empirical SMB (Sverdrup-Munk-Bretschneider) family of relations — with a choice of Bretschneider's method, Bretschneider with the water-depth (depth-limited) effect, or Wilson's method — and handles directional fetch via the effective-fetch, Saville, and Seymour methods. Essential for coastal engineers, harbour and port designers, and offshore engineers who need reliable design wave parameters and parametric spectra for structural design and planning. ## Key points - cgWindWaves forecasts design wave conditions — significant wave height (Hs), significant wave period (Ts), and the wave spectrum S(f) — directly from wind speed, direction, and fetch geometry in restricted-fetch water bodies. - It applies the semi-empirical SMB (Sverdrup-Munk-Bretschneider) family of relations, offering a choice of Bretschneider's method, Bretschneider with the water-depth (depth-limited) effect, or Wilson's method. - Directional wave effects are captured through the effective-fetch, Saville, and Seymour methods, accounting for irregular coastline geometry and multiple wind sectors. - The program generates Pierson-Moskowitz and JONSWAP parametric wave spectra plus a sample wave time series for downstream structural and mooring design. - The water region can be defined graphically, by coordinate table, or by importing nodal coordinates from a text file, and results are reported in metric or US units. - RAM CADDSYS supplies and supports cgWindWaves in India for coastal, harbour, and offshore engineering projects. - Forecasts design wave conditions — significant wave height (Hs), significant wave period (Ts), and the wave spectrum S(f) — directly from wind speed, wind direction, and fetch geometry. - Implements established semi-empirical SMB (Sverdrup-Munk-Bretschneider) wave-prediction relations, so results are traceable to published, peer-reviewed methods rather than a black box. - Handles restricted-fetch water bodies — harbours, marinas, lakes, reservoirs, sheltered bays — where fully-developed-sea formulas do not apply. - Lets the engineer define the water region three ways: clicking nodes on the built-in graphical map, typing X/Y coordinates into a table, or importing nodal coordinates from a text file. - Accounts for directional spreading via the effective-fetch, Saville, and Seymour methods, giving more realistic wave estimates for irregular coastlines. - Produces Pierson-Moskowitz and JONSWAP wave spectra plus a sample time series, ready to feed downstream structural, mooring, and breakwater design. - Works in either metric or US units and generates preview and printed calculation reports for documentation and review. - Lightweight single-screen Windows desktop tool — all inputs and forecasted results are shown together, with context help and an online manual. ## Why engineers pick it - **Verified Semi-Empirical Methods** — Implements the SMB (Sverdrup-Munk-Bretschneider) family — Bretschneider, Bretschneider with depth-limited effect, and Wilson's method. - **Parametric Spectral Output** — Generates Pierson-Moskowitz and JONSWAP wave spectra plus a sample wave time series. - **Directional Fetch Treatment** — Captures irregular coastline geometry and multiple wind sectors through the effective-fetch, Saville, and Seymour directional methods for realistic restricted-fetch wave estimates. - **Design Wave Parameters & Reports** — Outputs significant wave height (Hs), significant wave period (Ts), and the wave spectrum on a single screen. ## Capabilities - **Wind-to-Wave Forecasting (Hs, Ts, Spectrum)** — From a defined water region, mean wind direction, and wind velocity, cgWindWaves computes the significant wave height Hs, the significant wave period Ts, and the wave spectrum S(f). It is a forecasting/analysis tool for restricted-fetch regions where wave refraction is negligible. - **Multiple Semi-Empirical Prediction Methods** — The user can select among Bretschneider's method, Bretschneider with the water-depth (depth-limited) effect, and Wilson's method — all from the SMB (Sverdrup-Munk-Bretschneider) family. - **Directional Fetch Treatment** — Directional wave effects are handled by the effective-fetch method, Saville's modified weighted-average method, or Seymour's energy-averaged spectral method. - **Parametric Wave Spectra** — Generates parametric wave spectra (Pierson-Moskowitz and JONSWAP) and a sample wave time series from the computed parameters. - **Flexible Water-Region Definition** — The water body outline can be created graphically by clicking nodes on the included map package, entered as an X/Y nodal-coordinate table, or read from an external text file. - **Reporting and Units** — Works in metric (m, km, m/s, km/h) or US units (ft, miles, ft/s, mph), with on-screen preview and printed calculation reports plus theoretical-summary printouts and PDF examples for documentation. - **Wind-Wave Hindcasting** — Convert recorded or design wind speeds and directions into wave parameters for return-period and extreme-condition assessment in restricted-fetch settings. - **Effective Fetch Analysis** — Directional fetch treatment for complex coastline geometries through the effective-fetch, Saville, and Seymour methods, accounting for multiple wind sectors and sheltering. - **Wave Spectrum Generation** — Generation of parametric Pierson-Moskowitz and JONSWAP wave spectra, plus a sample time series, for input to structural and mooring analysis software. - **Depth-Limited Wave Prediction** — Bretschneider's method with the water-depth (depth-limited) effect limits wave growth in shallower restricted-fetch waters such as harbours and reservoirs. - **Flexible Region Definition & Reporting** — Define the water region graphically, by coordinate table, or from a text file, then preview and print calculation reports in metric or US units. ## Applications - **Harbour, Marina & Port Wave Estimation** — Estimating design wave heights and periods inside sheltered, restricted-fetch basins such as harbours and marinas, where wind locally generates the governing waves. - **Coastal & Marine Structure Design Inputs** — Producing the significant wave height, period, and spectrum needed as loading inputs for breakwaters, quay walls, jetties, and other coastal/marine structures. - **Lakes, Reservoirs & Inland Water Bodies** — Forecasting wind-generated waves on lakes and reservoirs to assess fetch-limited wave action on dams, embankments, intakes, and shoreline protection. - **Wind-Wave Hindcasting from Wind Records** — Converting recorded or design wind speeds and directions into wave parameters for return-period and extreme-condition assessments in restricted-fetch settings. - **Preliminary Offshore / Sheltered-Water Assessment** — Quick first-pass wave-climate estimates for sheltered or semi-enclosed water regions to support planning and feasibility before detailed spectral or CFD wave modelling. ## In depth ### Why do restricted-fetch water bodies need a dedicated wind-wave forecasting tool? Because fully-developed-sea wave formulas do not apply inside harbours, marinas, lakes, and reservoirs, cgWindWaves applies fetch-limited semi-empirical relations built specifically for these sheltered, wind-driven wave environments. cgWindWaves is built for restricted-fetch water bodies — harbours, marinas, lakes, reservoirs, and sheltered bays — where fully-developed-sea formulas do not apply. The engineer defines the water-region outline directly, then supplies the mean wind direction and velocity, and the program forecasts the Hs, Ts, and spectrum S(f) that specific restricted-fetch geometry would generate. Two further refinements keep the forecast realistic. Bretschneider's method with the water-depth (depth-limited) effect accounts for shallow water capping wave growth in harbours and reservoirs, while the effective-fetch, Saville, and Seymour directional methods capture irregular coastline geometry and multiple wind sectors for more realistic restricted-fetch wave estimates. The result is a design wave estimate coastal, harbour, and offshore engineers can use for structural design and planning before committing to detailed spectral or CFD wave modelling. ### How does cgWindWaves turn wind data into design wave parameters? The engineer defines the water-region outline and the wind conditions, and cgWindWaves runs the selected SMB-family relation and directional-fetch method to compute Hs, Ts, and the wave spectrum on a single screen. The water-region outline can be created three ways: clicking nodes on the included graphical map, typing X/Y coordinates into a table, or importing nodal coordinates from an external text file. With the region set, the engineer enters the mean wind direction and velocity, chooses a prediction method — Bretschneider's method, Bretschneider with the water-depth (depth-limited) effect, or Wilson's method — and selects how directional fetch is treated: the effective-fetch method, Saville's modified weighted-average method, or Seymour's energy-averaged spectral method. cgWindWaves then computes the significant wave height Hs, the significant wave period Ts, and the wave spectrum S(f), and displays all inputs and forecasted results together on a single main screen. It also generates parametric Pierson-Moskowitz and JONSWAP wave spectra and a sample wave time series, ready to feed downstream structural, mooring, and coastal-structure design tools. Results and calculation reports — including theoretical-summary printouts — can be previewed on-screen and printed in either metric or US units for documentation and review. ## Questions ### What is cgWindWaves used for? cgWindWaves forecasts wind-generated waves in restricted-fetch water regions. From a defined water region, the mean wind direction, and the wind velocity, it computes the significant wave height (Hs), the significant wave period (Ts), and the wave spectrum S(f) for coastal, harbour, and offshore engineering. ### Who develops cgWindWaves? cgWindWaves is developed by RUNET (RUNET Software / RUNET Norway AS), a developer of structural and marine engineering software. It is part of the RUNET program family that also includes BETONexpress, STEELexpress, WOODexpress, and FRAME2Dexpress. ### Which wave-prediction methods does cgWindWaves use? It uses semi-empirical SMB (Sverdrup-Munk-Bretschneider) relations. The engineer can choose Bretschneider's method, Bretschneider with the water-depth (depth-limited) effect, or Wilson's method, with directional effects handled by the effective-fetch, Saville, or Seymour methods. ### Does cgWindWaves design to a structural code such as Eurocode or IS codes? No. cgWindWaves is a wave forecasting/analysis tool, not a code-based structural design tool. It computes wave characteristics (height, period, spectrum) from wind and fetch data; it does not perform member or structure verification to a design code. RUNET's separate products (e.g. BETONexpress, STEELexpress) are the Eurocode design tools. ### Can cgWindWaves generate a wave spectrum for further analysis? Yes. It produces parametric wave spectra — Pierson-Moskowitz and JONSWAP — together with a sample wave time series, which can be used as wave-loading input for structural, mooring, and coastal-structure analysis software. ### How is the water region defined? Three ways: graphically by clicking the outline nodes on the included map package, by entering the X and Y nodal coordinates in a table, or by reading the nodal coordinates of the outline from a text file. ### Does it account for water depth and shallow-water effects? Yes — one of the available formulations is Bretschneider's method with the water-depth (depth-limited) effect, which limits wave growth in shallower restricted-fetch waters. ### Does cgWindWaves support metric and US units? Yes. It works in metric units (m, km, m/s, km/h) or US units (ft, miles, ft/s, mph), and the unit system can be selected by the user. ### What kind of output and reports does it produce? All inputs and forecasted results appear on a single main screen, and the program provides on-screen preview and printed calculation reports, including theoretical-summary printouts; sample reports are available in PDF. ### Is cgWindWaves a Windows desktop application? Yes, cgWindWaves is a RUNET Windows desktop program. It is a focused single-purpose tool rather than a large modelling suite, with context-sensitive help and an online manual. ### What types of projects is cgWindWaves suited to? It is suited to restricted-fetch water bodies — harbours, marinas, sheltered bays, lakes, and reservoirs — where wind locally generates the design waves and refraction is negligible. For open-coast problems with significant refraction or diffraction, a full spectral wave model is more appropriate. ### Is cgWindWaves available in India through RAM CADDSYS? Yes. RAM CADDSYS supplies RUNET software, including cgWindWaves, to engineering professionals in India, with licensing and support. Contact RAM CADDSYS for current pricing, licensing terms, and a demonstration. --- Full page: https://www.ramcadds.com/products/cgwindwaves Pricing is quoted per territory and is deliberately not published. Talk to us: https://www.ramcadds.com/contact