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This report describes the procedure for generating sinusoidal waves in the clearwater towing tank in Institute for Marine Dynamics, St. John's by using the analog signal generator mounted on the wavemaker control panel. In the absence of final calibration of the wavemaker, theoretical guideline is recommended for choosing board span settings, etc.

Source: https://erdc-library.erdc.dren.mil/jspui/ This report presents an approximate method for estimating wind-wave growth and decay over flooded areas where there is a major effect from bottom friction because of dense vegetation.

Source: https://erdc-library.erdc.dren.mil/jspui/ A series of 36 unidirectional spectral waves was generated' to determine the relationship between wave generator control signal and measured response at seven locations in the model basin. Control signals consisted of combinations of three peak periods ranging from 1.0 to 2.0 sec, two zero-moment wave heights from 1 to 3 in., three spectral peak enhancement factors from 3.3 to 15, and two peak directions of 0 and -30 deg. Seven resistance or capacitance wave gages were centrally located 20 ft in front of the wave generator about its center line in a combination cross and 2-3-1-7 linear array. Descriptions of the spectral simulation and generation, time series and spectral analysis, frequency response, and wave grouping analysis are presented. Compariaors of predicted and measured peak period, zeromoment wave height, peak wave direction, frequency spectra, and directional spreading are presented and discussed. Frequency response and wave grouping statistics are calculated for each test case. This report consists of two volmes: Volume I consisting of the main text and Appendix A and Volume I1 consisting of Appendixes B-H.

Source: https://erdc-library.erdc.dren.mil/jspui/ This report provides a number of calculator programs useful in performing coastal engineering calculations, primarily in the areas of wave transformation and wave generation. Six programs are included for use with the HP41CV hand-held calculators which employ the Reverse Polish Notation (RPN). These programs can be used to compute linear wave parameters, orbital velocities, breaking wave height and direction, shallow-water wave forecasts, depth-limited breaking wave height, and wave transmission past a vertical barrier.

Source: https://erdc-library.erdc.dren.mil/jspui/ This report provides algorithms for a number of calculator programs useful in performing coastal engineering calculations, primarily in the area of wave transformations and wave generation. Six programs are included with different versions for use with hand-held calculators which employ either the Reverse Polish Notation (RPN) or the Algebraic Operating System (AOS). These programs can be used to compute linear wave parameters, orbital velocities, breaking wave height and direction, shallow-water wave forecasts, depth-limited breaking wave height, and wave transmission past a vertical barrier.

Source: https://erdc-library.erdc.dren.mil/jspui/ This report describes the design of the Los Angeles and Long Beach Harbors hydraulic model for investigation of harbor oscillation characteristics of the existing harbor and for evaluation of various proposed harbor modifications. The effects of wave refraction, diffraction, viscous friction, wave reflection, wave transmission through the harbor breakwaters, wave filters, and wave absorbers were considered. Wave generator design, automated model data acquisition and control, and model data analyses are also described. This report is the fourth in series Technical Report H-75-4 published under the general title "Los Angeles and Long Beach Harbors Model Study." A model distortion ratio of 1:4 and a vertical scale ratio of 1:100 (1:400 horizontal scale ratio) were selected to minimize the model area and to provide a vertical scale ratio where accurate model wave measurements could be assured. The model reproduces approximately 253 square miles of prototype area. Model limits were selected to enclose a strong convergence zone seaward of the harbor breakwater. Adjustment of the initial generated wave-front position in the model was necessary to compensate for model distortion and the maximum model depth of -300 ft mllw. The electrohydraulic wave generator used in the model study is composed of 14 separate 15-ft units for a total wave generator length of 210 ft and is capable of (A.) generating waves with a prototype period ranging from 15 to 600 sec, (B.) generating a wave with small variation in period and height between units, (C.) defining resonant response over a narrow period band, (D.) generating a variable wave height along the wave front , and (E.) generating a curved wave front. Performance requirements for the wave generator include : (A.) the amplitude error of the wave-paddle stroke for each unit must be less than 1 percent and (B.) the phase lag of the wave-paddle response from the electronic command signal between each of the 14 units must be less than 4 degrees. The four subsystems of the automated model data acquisition and control system include: (A.) digital data recording and controls, (B.) analog recorders and channel selection circuits, (C.) wave sensors and interfacing equipment, and (D.) wave generator units and control equipment. Model wave record analyses include the capacity for determination of : (A.) average, root mean square, and significant wave height and (B.) average period. Procedures for Fourier analysis and least-squares harmonic analysis of the wave record are also available. The hydraulic model can be used in a predictive mode to evaluate various proposed modifications to optimize the modifications from both a cost and functional standpoint. Potential future uses of the model include studies of (A.) dispersion of effluent from specific outfalls in the harbor complex, (B.) tsunami waves, (C.) effects of various coastal structures from Point Fermin to Huntington Beach, (D.) effects of artificial offshore islands or landfill seaward of the existing harbor breakwater on tidal circulation and wave conditions, (E.) tidal circulation in areas such as Huntington Beach, Bolsa Chica Wildlife Reserve, Alamitos Bay, etc., (F.) effect of various future harbor modifications on tidal circulation and wave conditions, (G.) studies of the physical environment in the harbor and surrounding areas, and (h.) wave and tidal circulation studies of the proposed Downtown and Queensway Marinas.

This report is intended to give a brief description of the ideas underlying the experiment of RWS and THD in the framework of JONSWAP 2 and the practical implications thereof. Some results of the preparation of this experiment are given. It is tried to explain some of the theoretical concepts in a simple manner. It has been found that it is desirable to obtain an interpretation of the spatial structure of seawaves in the framework of an international seawave research project, called JONSWAP 2. This project is aimed at testing theoretical concepts of wave generation and attenuation. The measurements can be used in the framework of this project but also for applications in other fields (marine engng., coastal engng. etc.). The technique for recording the waves will be an adaptation of existing stereophotographic procedures. It may be used for future investigations of wavephenomena. Based on considerations of the anticipated wave conditions and practical experience, specifications for equipment and procedures have been obtained. The organization, finances and material support have been agreed upon by Rijkswaterstaat and the Delft University of Technology. The experiment was initiated in January 1972; in September the experiment was incorporated in JONSWAP 2. The development of the equipment and the numerical analysis procedures has started. The realization of JONSWAP 2 is planned for September 1973, the publication of results in 1974 and 1975.

This report is intended to give a brief description of the ideas underlying the experiment of RWS and THD in the framework of JONSWAP 2 and the practical implications thereof. Some results of the preparation of this experiment are given. It is tried to explain some of the theoretical concepts in a simple manner. It has been found that it is desirable to obtain an interpretation of the spatial structure of seawaves in the framework of an international seawave research project, called JONSWAP 2. This project is aimed at testing theoretical concepts of wave generation and attenuation. The measurements can be used in the framework of this project but also for applications in other fields (marine engng., coastal engng. etc.). The technique for recording the waves will be an adaptation of existing stereophotographic procedures. It may be used for future investigations of wavephenomena. Based on considerations of the anticipated wave conditions and practical experience, specifications for equipment and procedures have been obtained. The organization, finances and material support have been agreed upon by Rijkswaterstaat and the Delft University of Technology. The experiment was initiated in January 1972; in September the experiment was incorporated in JONSWAP 2. The development of the equipment and the numerical analysis procedures has started. The realization of JONSWAP 2 is planned for September 1973, the publication of results in 1974 and 1975.

Landslides falling into water bodies can generate impulsive waves, which are a type of tsunamis. The propagating wave may be highly destructive for hydraulic structures, civil infrastructure and people living along the shorelines. A facility to study this phenomenon was set up in the laboratory of the Technical University of Catalonia. The set-up consists of a new device releasing granular material at high velocity into a wave basin. A system employing laser sheets, high-speed and high-definition cameras was designed to accurately measure the high velocity and geometry of the sliding mass as well as the produced water displacement in time and space. The analysis of experimental data helped to develop empirical relationships linking the landslide parameters with the produced wave amplitude, propagation features and energy, which are useful tools for the hazard assessment. The empirical relationships were successfully tested in the case of the 2007 event that occurred in Chehalis Lake (Canada).

In this paper a new wave pool concept is presented using ship hulls as wave generators. To evaluate the potential of such a concept a towing tank experiment is conducted to investigate ship wave generation in a confined space. In the towing tank experiment various hull sizes and velocities are examined to maximize the generated wave height. The laboratory data shows that when blocking of the cross section of the pool by the hull is large, the large return flow significantly influences the wave height. This is in contrast to the open water case where the return flow is much smaller and therefore is not incorporated in wave height predictions. Based on the results of the physical model tests an optimum hull size and velocity are derived to maximize the potential use for surfing and a preliminary design of the wave pool is proposed.

Reflections at the wave-maker and tank boundaries can be a dire problem in wave tank experiments. Often, such reflections cannot be avoided. The present paper proposes an approach to quantify this influence via numerical flow simulations. It is straight-forward to redo the actual experiment "virtually" in a flow simulation, featuring full reflections as present in the wave tank experiment. It is shown that reflections at the wave-maker and domain boundaries can be nearly eliminated by applying appropriate boundary conditions in combination with domain-internal wave generation approaches. This is demonstrated for the case of a boat subjected to regular deep water waves from starboard side. Flow simulations based on the Euler equations are performed for a realistic model scale setup, in a similar manner as experiments in a narrow wave tank would be performed. Subsequently, the simulation is repeated in such a way, that undesired wave reflections at both the domain boundaries and the wave-maker are minimized. From the comparison, it is possible to separately assess the influence of wave reflections at the wave-maker as well as at the wave tank boundaries.

Günther F. Clauss is one of the most influential and distinguished international experts in the field of ocean engineering. With 50 years of activities in the field, often in collaboration with national and international colleagues, he has contributed significantly to the visibility and progress of ocean engineering as a research discipline. In his scientific contributions, he has repeatedly established new ideas and set standards. His research contributions include the design, installation and decommissioning of offshore structures, the analysis of loads and motions on floating structures and ships, the development of SAR and oil spill response systems and deep-sea technology. Across all areas, from fundamental to application driven research, one topic always stood out – the investigation, simulation and experimental modelling of natural waves aiming at a comprehensive deterministic analysis of offshore structures and ships in natural sea states and extreme waves. From linear superposition of regular waves to the generation of highly nonlinear wave phenomena, from wave-structure interaction to marine oil spill response technologies this paper attempts the almost impossible task: to deliver an overview over 50 years of research by highlighting selected topics, telling the story of Günther F. Clauss who has conquered the inner space.