DE102018009216A1 - Device for reducing wave movements of floating structures - Google Patents

Abstract

The invention relates to a device for reducing wave movements of floating structures, in front of which a series of pontoons are arranged in a line with a gap between them. The object of the invention is to achieve a reduction in wave movements of floating structures and floating houses in particular The invention can be used in general for the protection of floating structures and in particular for the protection of floating houses or floating settlements. The effect according to the invention is achieved by a series of pontoons arranged in a line with a gap between them, by incoming high-energy water waves due to diffraction, interference and reflection can be converted into short-period, short-comb waves. The short-period, short-comb waves excite floating buildings less to wave movements, so that they are perceived less disturbing psychologically. In addition, the short-period, short-comb water waves degrade their energy more quickly due to turbulence.

Description

The invention relates to a device for reducing wave movements of floating structures, in particular in inland lakes, using floating pontoons, which are arranged in a line on the sea side with a gap.

The obvious solution, i.e. A heaped-up or pre-assembled mole is not required for the intended primary application in inland lakes of open-cast mining holes, since there is a steep drop in water depth and, moreover, the subsoil generally does not meet the strength requirements. Therefore, floating devices are in demand.

In the past, vertical protective structures with a permeable front were investigated and various solutions were described to improve the relationship between effort and benefit. As a result, it was stated that vertical structures with a permeable front offer a strong improvement in the reflective properties and also increase the stability of the structure. Horizontal arrangements according to the solution according to the invention have not yet been mentioned, although they exploit previously unused effects using the Huygensian effect and the interference in the close range.

A number of different horizontal arrangements of floating wave breaking and calming devices are known. Various options are described for rejecting waves, damping waves or combining the breakwater function with energy generation.

For example, in EP0210978B1 described a zigzag wave deflector. The stated aim of this device is to prevent waves from entering the interior of a boat port through the port entrance. For this purpose, two folded zigzag wave deflectors are used in a folding version in cooperation with a third, firmly established zigzag wave deflector.

In contrast, the solution according to the invention is restricted to a reduction in the wave movements of floating structures, with a substantial reduction in expenditure.

It is also out US9556573 "Wave attenuation system and method" known a wave attenuation system that protects an extensive water area in an arrangement of several breakwater attenuators.

In contrast, the focus of the solution according to the invention is not aimed at protecting an extensive water area, but rather at reducing the wave movements of floating structures. The essential difference is evident in the fact that even larger, but short-period wave amplitudes can occur in the vicinity of the pontoon chain of the solution according to the invention.

Another technical solution for calming waves after US20060225634A1 uses "Pneumatically Stabilized Platforms". Here, an arrangement of containers with an open bottom is rigidly coupled and connected to other containers by air ducts. When sea-side wave fronts enter the cellular field of containers, equalizing air flows from the containers ultimately result in leveling of the waves beyond the cellular field of containers.

This solution is too complex to reduce the wave movements of floating structures on inland lakes.

According to the state of the art, wave-breaking elements are usually arranged in a line without a gap, thus also in accordance with the USA trade mark "Superflex Mooring Breakwater". A flexible anchoring rope according to the utility model DE20317006U1 serves to secure the location.

In contrast, the solution according to the invention uses a series of pontoons which are arranged in a line with a gap. However, there is no reason why the solution according to the invention is also a flexible anchoring rope according to the utility model DE20317006U1 to secure the location of the pontoons.

All of these devices are indeed suitable for achieving wave damping. Disadvantages of all these devices are their high expenditure and / or the inadequate suitability in inland lakes for reducing the wave movements of floating structures.

The invention has for its object to achieve a reduction in wave movements of floating structures and floating houses in particular.

In contrast to all known approaches, this problem is solved paradoxically in that the device according to the invention initially builds up higher wave amplitudes in the vicinity of the pontoons by superimposing wave fronts of adjacent distances and thus apparently increases the risk. Whose notwithstanding, the useful effect of the device according to the invention develops in many ways.

First of all, the useful effect unfolds when the in 1 in the marked area 1 form short-period, short-comb wave overlays, so that the buildings to be protected are surrounded by several wave valleys and wave crests. Under these circumstances, the influences of wave valleys and wave peaks balance out and the resulting movement is much smaller than if the original elongated wave attacked the structures to be protected.

Secondly, the useful effect unfolds in that the short-period, short-comb waves are higher in frequency than the natural frequency of the buildings to be protected. Under these circumstances, the effect of wave excitation on the structures to be protected is substantially damped, so that the wave movements of the structures to be protected are minimized.

Thirdly, the useful effect unfolds by reflecting part of the waves on the pontoons so that the reflected parts cannot attack the floating structures.

Fourth, the useful effect unfolds, since the patented use of the Huygens effect with interference in the vicinity of the pontoons is largely independent of tolerances of the device and the weather-related variations of the waves, since the principle of action is not based on the use of wavelength-dependent effects.

Fifthly, the choice of the gap between the pontoons can influence the sedimentation, which would otherwise result in all previously known methods with a wave calming.

Sixth, the useful effect unfolds in that the water in the area of the short-period, short-comb waves breaks down its wave energy faster due to the turbulence.

For the seventh, the useful effect unfolds not least because the pontoons themselves absorb wave energy due to their inertia and thus contribute to reducing the wave amplitudes on the land side of the series of pontoons.

The patented use of the Huygens effect with interference fulfills its effect in the vicinity of the pontoons even if the incident wave fronts meet the line of the pontoons at an angle.

The useful effect is achieved according to the invention by the features of the first claim. Further expedient embodiments of the invention are the subject of the further back-related subclaims.

The essential approach of the present device according to the invention consists in a reduction in the wave movements of buildings known per se from the prior art, with complex piling of moles or the use of uninterrupted lines of floating breakwaters being replaced by a gaping arrangement of pontoons. In contrast to known solutions, the Huygensian effect comes into play here, which means that every gap in the pontoon row becomes the starting point for a new circular wave. These so-called elementary waves generate interference through superimposition. Because of this, longer waves on the sea side in the vicinity of the pontoon row are converted into short-period, short-comb waves. With an advantageous design of the solution according to the invention, the frequency range of the short-period, short-comb waves lies above the natural frequency of the floating structures. This means that the structures to be protected are stimulated to move to a much lesser extent than if the structures were directly exposed to the longer waves with higher energy levels on the lake side.

The device according to the invention should be based on the 1 to 10th are explained in more detail in different versions and their effects. The schematic structure of the device according to the invention for reducing wave movements of floating structures provides 1 represents.

1 shows the incoming wave 2nd on the pontoons arranged in a line 3rd with gaps 4th bumps. Every gap 4th is the starting point for semicircular elementary waves according to the Huygensian effect 5 . The elementary waves 5 overlap and form short-period, short-comb waves 6 , so that the structures to be protected are surrounded by several wave valleys and wave crests.

2nd shows an embodiment of the device according to the invention for reducing wave movements of floating structures according to claim 1, 4 and 5, in which between the floating houses or floating settlements and / or other structures to be protected or the shore analog 3rd and 4th smaller boats and yachts or a jetty are placed.

3rd shows an embodiment of the device according to the invention for reducing wave movements of floating structures according to claim 1 and 2, in which pontoons are aligned according to the topological conditions to a prevailing main wind direction and due to their rectangular or rhombic shape incoming waves on the one hand sea side and on the other hand at a flat angle to reflect on the floating buildings.

4th shows an embodiment of the device according to the invention for reducing wave movements of floating structures according to claims 1 and 3, in the pontoons due to their rounded base reflect incoming wave fronts in many ways. This option is particularly indicated when there is no predominant wind direction.

5 shows the result of a Fourier analysis using an exemplary simulated deep-water wave with a transverse and circular portion. 5 for the device according to the invention for reducing wave movements of floating structures according to claims 1 to 8, the shift of the excitation frequency from the fundamental wave of the original elongated wave (fundamental wave) to a wave mixture with higher-frequency components (harmonics). The ordinate quantifies the respective proportions.

6 shows the shift of the excitation range of floating buildings in relation to the natural frequency using the example of a floating house. It can be seen that, in relation to the frequency range of the original elongated wave, the structures to be protected are relocated to a higher-frequency part of a lower amplitude of the excitation after the device according to the invention has an effect. Since this range lies above the natural resonance, the shifted excitation has a further reduced influence on the wave movement of the structures to be protected.

7 shows how the psychological disturbance perception of residents of floating buildings in relation to wave acceleration and wave period shifts with the solution according to the invention for floating buildings from psychologically felt "INAPPROPRIETY" to "ENDURABLE" or even "NOT PERCEPTABLE". The rating of 7 follows the statements of DI Harald Melwisch recognized in specialist circles in his writing "Seasickness mathematically calculated".

8th shows pontoons ( 3rd ) with side relief structure ( 14 ). On the side walls of the relief structure ( 14 ) If the wavelength of the water λ is small compared to the structure profile, directional reflections similar to those of optical reflections occur. Due to the wavelength λ of water, which is several orders of magnitude larger than that of light, λ will practically lie in the dimensions of the structural profile. In these cases, water waves deviate from electromagnetic waves and diffuse reflection occurs. Both forms of reflection, ie the directed and diffuse reflection, act in the sense of the solution according to the invention. It also has an arrangement according to 8th the advantage that a linear alignment of the pontoons is easier to achieve by means of a tension cable or tension chain.

9 shows an example arrangement for which the reflectance is calculated as a function of the angle of incidence of the wavefront ( 10th ). The degree of reflection determines the proportion of incoming wave energy which, due to the reflection, cannot penetrate to the floating structures to be protected. The example arrangement uses an isosceles shape of a rectangular pontoon geometry with a leg length, which is typical for wavelengths on inland lakes. In the example arrangement, the distance to the adjacent pontoon corresponds to the diagonals. 10th shows that in this configuration waves with an angle of incidence <18.4 ° and> 161.6 ° are completely reflected. Large areas experience at least 50% reflection.

The invention is primarily applicable to the protection of floating houses or floating settlements on inland lakes from destruction by storms. Furthermore, it is important for everyday living in floating houses or floating settlements to reduce wave movements and thus counteract the health consequences of wave movements (seasickness).

A dimensioning example of the new device according to the invention for reducing wave movements of floating structures is intended to underline the crucial importance of reducing wave movements. Under the conditions that the incoming wavelength on the sea side is smaller than the length of the structures to be protected (less than ½) and that the structures are located in the vicinity of the pontoons (distance in the range of one to three wavelengths), the wave movement of the structures to be protected can be reduced by one to two orders of magnitude.

Reference symbol list

1

marked area short-period, short-comb wave overlays

2nd

original elongated shaft

3rd

a pontoon from a gaping series of pontoons

4th

Gap within the row of pontoons

5

Huygensian elementary wave

6

short-period, short-comb wave

7

floating structures, e.g. Floating house

8th

web

9

Boats, yachts etc.

10th

Shoreline

11

Direction of propagation of the attacking wavefront

12

Direction of propagation of the reflected wavefront

13

Tension rope or tension chain for linear alignment

14

Surface with micro-Fresnel reflection

• 1 Vorrichtung der erfindungsgemäßen Lösung
• 2 Ausführungsbeispiel mit Steg und Booten
• 3 Ausführungsbeispiel für Standorte mit ausgeprägter Vorzugswindrichtung
• 4 Ausführungsbeispiel mit gerundeter Grundfläche der Pontons
• 5 Fouriertransformation der Erregung
• 6 Einfluss der Erregerfrequenz eines Schwimmenden Hauses
• 7 Störempfinden von Wellenbewegungen nach D.I. Harald Melwisch
• 8: Fläche mit Micro-Fresnel-Reflexion
• 9: Beispielanordnung
• 10: Reflexionsgrad vs. Einfallswinkel für die Beispielanordnung

Compilation of the figures

• 1 Device of the solution according to the invention
• 2nd Embodiment with dock and boats
• 3rd Example for locations with a pronounced preferred wind direction
• 4th Embodiment with a rounded base of the pontoons
• 5 Fourier transform of excitation
• 6 Influence of the excitation frequency of a floating house
• 7 Disturbance of wave movements according to DI Harald Melwisch
• 8th : Surface with micro-Fresnel reflection
• 9 : Example arrangement
• 10th : Reflectance vs. Angle of incidence for the sample arrangement

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 0210978 B1 [0005]
• US 9556573 [0007]
• US 20060225634 A1 [0009]
• DE 20317006 U1 [0011, 0012]

Claims (9)

Device for reducing the wave movements of floating structures, in front of which a row of pontoons are arranged in a line with a gap, on the lake side, characterized in that between the row of pontoons and the floating structures there is a water area in which short-periodic, form short-wave overlays due to the Huygensian effect and these flood the floating buildings. Device for reducing wave movements of floating structures Claim 1 , characterized in that the pontoons lying in front of the floating structures are aligned in accordance with the pronounced preferred wind direction and, due to their rectangular or rhombic shape, reflect incoming waves on the one hand on the sea side and on the other hand at a flat angle to the floating structures. Device for reducing wave movements of floating structures Claim 1 , characterized in that the pontoons lying in front of the floating structures have a rounded base and thus reflect incoming wave fronts in many ways. Device for reducing wave movements of floating structures Claim 1 , characterized in that the floating structures are a floating house or a series of floating houses. Device for reducing wave movements of floating structures Claim 1 , characterized in that a jetty or smaller boats and yachts are placed between the floating houses or other structures to be protected and the shore. Device for reducing wave movements of floating structures Claim 1 , characterized in that the series of pontoons arranged in a line with a gap between them are connected to one another via bridges and act as a bridge. Device for reducing wave movements of floating structures Claim 1 , characterized in that one or more or all of the pontoons of the pontoons arranged in a row with a gap are used for energy generation and / or energy storage. Device for reducing wave movements of floating structures Claim 1 , characterized in that the pontoons arranged in a line in a row with a gap between them are rotated at an angle to the shoreline in order to achieve better effectiveness with pronounced preferred wave directions. Device for reducing wave movements of floating structures Claim 1 , characterized in that the side surfaces of the pontoons arranged in a row in line have a relief structure and thus act as a micro-Fresnel reflector.

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