Javier L. Lara

• PhD Civil Engineering
• Head of Department at University of Cantabria

The aim of this work is to extend the hydrodynamics analysis carried out in the 1st FOWT Comparative Study with the non-linear interaction under different current loadings (in magnitude and direction) to provide recommendations about the spacing between floating offshore wind turbines (FOWT). Therefore, a numerical wave tank (NWT) is developed in O...

Historically, flooding and erosion challenges in coastal areas have been addressed through conventional gray/rigid structures such as breakwaters, dikes, and walls (Morris et al., 2017). As a consequence of the context of climate change, which is accompanied by a global biodiversity crisis and an increasing risk to coastal systems and communities,...

Coastal areas are particularly vulnerable to climate change due to their exposure to mean sea-level rise and an intensification in the frequency and intensity of extreme events. Among the most vulnerable areas in Europe are the coastal urban areas of the Macaronesia Islands territories, since they are characterized with urban settlements in low lan...

Coastal zones have consistently been among the most appealing settlement areas due to their proximity to the sea, rich natural resources, and the high quality of life they offer (Lamberti et al., 2005). However, these regions are affected by climate change impacts, such as sea-level rise, storm surges, and an increased intensity of extreme weather...

Low-crested detached breakwaters are affected by coastal hydro- and morphodynamics, due to complex wave-structure- seabed interactions, which impact their stability, namely due to scour effects. The scour phenomenon has been under study in several mobile-bed physical model research studies (e.g., Fredsøe et al., 1997, Sumer et al., 2000 and Sumer e...

The potential of predictive maintenance for critical port infrastructure, reducing risks and extending its life cycle, remains to be unlocked by suitable quantitative information that fosters predictive maintenance and sustained investments towards progressive climate-proofing of the infrastructure. The PI-BREAK (Predictive Intelligent system for B...

Recently, bulk drag coefficient ( C ˜ D ) formulations used to quantify wave energy dissipation by Rhizophora mangroves were developed from laboratory data; however, these formulations have not yet been validated with field data. Additionally, due to the complex geometry of mangrove trees within forests and spatial variability, common criteria for...

The recent destructive landslide tsunamis, such as the 2018 Anak Krakatau event, were fresh reminders for developing validated three-dimensional numerical tools to accurately model landslide tsunamis and to predict their hazards. In this study, we perform Three-dimensional physical modelling of waves generated by subaerial solid-block landslides, a...

In this paper, an innovative framework is introduced for assessing the impact of climate change on coastal structures, with a primary emphasis on modeling future climate conditions. The framework encompasses several key components: the development of a new climate emulator to facilitate multivariate extreme value analysis; a hybrid statistical–nume...

The performance of three models, namely the Two-Phase Volume-of-Fluid,the Two-Phase Volume-of-Fluid coupled with a Sub-grid bubble population model, and the Complete Two-Phase Euler, regarding the modelling of aerated flows in spillways chutes is presented and discussed.

Extreme events, enhanced by Climate Change may cause several damages on coastal critical infrastructures, whereas port services are even more sensible to climatic stressors than those physical assets (UNECE, 2013). Therefore, consideration of Climate Change (CC) induced variability is necessary within adaptation assessment frameworks (IPCC, 2014) t...

Among the newest strategies are nature-based solutions based on coastal ecosystems (Spalding et al., 2014; Jongman 2018). Such solutions have several co-benefits, such as habitat creation, increased water quality or carbon sequestration. However, these solutions may not be effective on their own in high-risk areas or in areas where there is not eno...

Landslide-generated tsunamis are a relevant source of hazard for coastal areas. In this paper, the preliminary modelling results of tsunamis generated by deformable landslides by using computational fluid dynamics (CFD) methods, in OpenFOAM, is presented. The numerical approach presented here consists in modelling the granular material by using a C...

Composite vertical breakwaters are coastal structures used to defend port basins from waves in intermediate and deep water conditions. In order to safely use the inner side of harbors, it is important to limit wave overtopping. Parapet walls are used for this purpose. To improve the hydraulic efficiency of the parapet wall with a fixed crown wall h...

Nowadays, the existence of a huge number of aging harbor defense structures and climate change-induced forcing variability highlight the need for a methodology able to deal with uncertainties which arise during the design of new and above all upgraded structures. In the present work, a probabilistic design methodology based on the Monte Carlo simul...

Upgrade of aging harbor breakwaters is a worldwide problem, whose urgency is enhanced by the effects of climate change on coastal areas. In this context, the present work contributes to improve current understanding of the hydraulic response of damaged and upgraded rubble-mound breakwaters, providing also a methodology for the implementation of an...

A new numerical methodology reaching an improved characterization of the historical harbor wave agitation climate is presented in this work. A detailed frequency-direction wave spectrum definition of wave agitation patterns within harbor basins is achieved, providing an in-depth description of the whole multidirectional and multireflective wave pat...

This paper presents numerical investigations with experimental comparisons of random wave induced loads on the external walls of a large scale Oscillating Water Column (OWC) device. The objective is to investigate the capability of a numerical model that uses the Reynolds Averaged Navier–Stokes (RANS) equations to accurately reproduce extreme wave...

The effects of climate change on coastal areas are expected to significantly influence the risk for port operations. In the present work, a novel methodology for the quantitative assessment of the performances of upgraded rubble-mound breakwaters under a changing climate is proposed. For each considered upgrading option, the failure probability rel...

Most existing analytical and numerical models to quantify wave energy attenuation attributed to saltmarshes are based on the definition of a drag coefficient that varies with vegetation and wave characteristics and requires calibration, i.e., a case-specific variable. With the aim of determining a new variable to estimate wave energy attenuation wi...

The good performance of the port activities in terminals is mainly conditioned by the dynamic response of the moored ship system at a berth. An adequate definition of the highly multivariate processes involved in the response of a moored ship at a berth is crucial for an appropriate characterization of port operability. The availability of an effic...

In this work, a recently developed numerical model, capable of solving the hydro- and morphodynamics of the cross-shore beach profile, is used to gain insight into the relevant processes driving the generation of a breaker bar. The bedload and suspended sediment transport contributions are analysed separately. It has been shown that the bedload tra...

Salt marshes and mangrove forests provide critical ecosystem services such as reduced sediment erosion and increased hydrodynamic buffering. Sediment transport and hydrodynamics can be influenced by specific functional traits of the plants (for example, flexibility vs. rigidity) and community traits (for example, spatial density). While there is a...

Numerous tsunami numerical models have been proposed, but their prediction accuracies have not been directly compared. For quantifying the modeling uncertainties, the authors statistically analyzed the prediction results submitted by participants in the tsunami blind contest held at the 17th World Conference on Earthquake Engineering. The reproduci...

An accurate estimation of the historical harbour wave agitation is fundamental for many practical applications, such as port downtime analyses. In practical harbour agitation studies, usually based on numerical propagations from offshore wave climate towards a harbour (wave downscaling), the accuracy in defining the outer wave climate has an impact...

The aim of this work is to validate and analyze with the numerical model OpenFOAM, the nonlinear interaction of a WEC under regular waves using the Overset framework. Previous techniques, such as deforming grid approaches, present problems to handle large body motions when modelling wave-structure interactions. Therefore, by means of the Overset me...

Spillway design is key to the effective and safe operation of dams. Typically, the flow is characterized by high velocity, high levels of turbulence, and aeration. In the last two decades, advances in computational fluid dynamics (CFD) made available several numerical tools to aid hydraulic structures engineers. The most frequent approach is to sol...

This video shows the results of concentration fields produced by breaking waves simulated with the numerical model IH2VOF-SED. The top panel shows results during the first waves of the simulation, when the bathymetry is still nearly flat. The bottom panel shows the results after 24 minutes of wave action, when the bathymetry evolved forming a break...

This study presents the new advances achieved in the field of harbour agitation climate assessment. Based on the improvement of an elliptic mild-slope model (MSP), which realistically reconstructs waves inside any-sized basin, represented by high-detailed unstructured meshes, and forced by real-shaped outer spectral data. A new solver is proposed f...

In this work, a new numerical model for cross-shore beach profile evolution, IH2VOF-SED, is developed. It consists in the bidirectional coupling of a 2D RANS hydrodynamic solver and a sediment transport module. The resulting model is extensively validated against three benchmark cases at different scales, attending to the hydrodynamics, bottom shea...

Climate change studies already reported sea level rise as an accepted scenario, which induces changes in nearshore wave conditions. A large range of new experiences including water level, run-up, overtopping, hydrodynamic data for different wave steepnesses and directions was performed in the Leibniz Universität Hannover (LUH) wave basin for a rubb...

Air entrainment is common in free surface flows in large hydraulic structures (e.g., spillways, chutes, energy dissipation structures) and must be considered to assure an effective and safe operation. Due to the large size of the prototype structures, it is infeasible to model individual air bubbles. Therefore, using the OpenFOAM toolbox, an effici...

Although mangroves reduce the daily risk of flood for millions of people, it is still difficult to estimate the protection they provide for variable wave conditions and forest characteristics. This aspect is crucial for the promotion of conservation and restoration of mangrove forests and for the estimation of how the coastal protection service the...

Localized air-entrainment in hydraulic structures typically occur at geometry continuities or impinging flows. Laboratory data of an impinging jet experiment (Chanson & Manasseh, 2003) is used to evaluate and compare the performance of a volume-of-fluid and a two-phase Euler models. Both are included in the open-source OpenFOAM software toolbox (Op...

Estimation of the flow energy dissipation induced by an ecosystem that accounts for its characteristics (i.e. biomechanical properties, morphology, density) and the incident hydrodynamic conditions is crucial if ecosystem-based coastal protection measurements want to be implemented. Characterization of a vegetated ecosystem by measuring leaf traits...

There are coastal areas which are particularly prone to landslide-generated tsunami risk. The destructive effects caused by the impulsive waves, generated by landslide sources, can be strongly magnified by the characteristics of the so-called "confined geometries" (e.g. bays, reservoirs, lakes, volcanic islands, fjords, etc.). Complicated physical...

This study considers the wave overtopping loads on a building behind a rubble mound breakwater using 2D numerical modelling. The building will be used as Coast Guard station in Greystones Marina, which is located on the Irish Sea. Similar studies, using physical modelling, were carried out recently by Watson et al. (2018) and Park et al. (2017). Th...

The use of CFD for numerical representation of laboratory wave flume and basins, commonly known as numerical wave tanks (NWT), has become more popular in recent years with the aim of improving knowledge in the field of wave-structure interaction (WSI), both fixed and floating, due to advances that have been made in numerical modelling, mainly with...

Dentro del diseño de cajones de hormigón para la construcción de diques verticales, se ha definido unanueva metodología para el cálculo de las solicitaciones tridimensionales y la estabilidad hidráulica asociadapara todas las fases constructivas de los mismos, basada en el modelado numérico CFD (ComputationalFluid Dynamics) tridimensional y las téc...

Bridge pier scour poses major concerns for public safety and riverine communities because of its ability to undermine pier foundations. A new collar design is introduced as an improvement on the existing Flat Plate Collar (FPC). Uniquely, the three-dimensional collar is specifically designed to contain the horseshoe vortex and guide it safely downs...

In this paper, an extended numerical analysis of the “confined-crest impact” (hereinafter referred as “C-CI”), induced by non-breaking waves on recurved parapet walls, is presented to better understand the physics and characteristics of this impulsive wave phenomenon, which significantly depends on the geometry of the parapet (here made by a sector...

In this work, we present several applications of the 2D-3D multi-domain couplings for Navier-Stokes models developed and validated in its companion (Di Paolo et al. (0000), submitted). The methodology is used to carry out some relevant simulations which include long regular and irregular waves, solitary wave propagation on a shallow foreshore, focu...

VIDEOS: 1) Wave overtopping for oblique waves on a vertical breakwater on a rubble-mound foundation (https://vimeo.com/456919845) 2) Regular waves interaction with a vertical breakwater on a rubble-mound foundation (https://vimeo.com/456919285) 3) Coupled mooring analysis of a semisubmersible floating offshore wind platform using the Overset framew...

Port development -as key aspect of sustained economic growth- implies large investments in coastal structures, increasing the risk of structural failures and operational stoppages due to coastal hazards. Then, this paper presents a new approach to statistically characterize and simulate the long-term wave climate to be applied in port risk assessme...

This paper and its companion (Di Paolo et al. (b), submitted) present near-far field coupling schemes of Navier-Stokes (NS) equations for high-fidelity numerical modelling of wave generation, transformation and interaction with structures. The computational domain is subdivided into near and far field zones (2D and 3D subdomains, respectively) in w...

The accurate modeling of the landslide‐generated tsunami characteristics in the so‐called near‐field is crucial for many practical applications. In this paper, we present a new full‐3‐D numerical method for modeling tsunamis generated by rigid and impermeable landslides in OpenFOAM® based on the overset mesh technique. The approach has been success...

The nonlinear interaction between waves and floating wave energy converters (WECs) has become in the recent years one of the biggest challenges for wave power industry. Large displacements of real structures demand accurate and robust numerical tools to solve the problems more efficiently. However, all this nonlinear interactions between the floati...

This paper presents an innovative vertical breakwater cross-section integrating an overtopping wave energy converter, named OBREC-V, and the analysis of its hydraulic performance and stability response to hydraulic loading. The structure is composed of a vertically-faced caisson with a sloping ramp on the top, a reservoir and a set-back crown-wall....

Multi-environment reactors are an innovative alternative to simplify conventional Biological Nutrient Removal (BNR) treatment trains as they are more compact and can adapt to existing quality requirements. However, maintaining the desired environmental conditions in different zones of the reactor implies the need for deflectors or mixing devices th...

The 7th International Conference on The Application of Physical Modelling in Coastal and Port Engineering and Science, Coastlab18, was organized in Santander, Spain, from 22 to 26 May 2018, by the Instituto de Hidráulica Ambiental de la Universidad de Cantabria, IHCantabria. The conference was organized under the auspices of the International Assoc...

SE@PORT project aims to improve the overall performance of a single Wave Energy Converter (WEC), developing hybrid systems that combine the use of two technologies over and above individual working principles. An oscillating water column (OWC) and an overtopping converter (OBREC-type in this case) have been designed to be included in Las Palmas har...

AnoxAn is a novel multi-environment reactor for biological nutrient removal (BNR) from wastewater. Although its biological efficacy has been demonstrated on a pilot scale, hydrodynamics is observed to significantly affect the performance of AnoxAn. To study its complex hydraulic behaviour, a model based on Computational Fluid Dynamics 3D (CFD) is c...

In recent years, the increase of computational resources make numerical models for studying real fluid-structure interactions very popular.Thus, strong, robust and accurate numerical tools are needed to solve problems more efficiently.Movable structures like wave energy converters (OWC) or floating offshore wind turbines (FOWT), moored ships or flo...

Probabilistic design analysis is highlighted as a powerful tool during the design/planning phases due to its capability to simulate the hydraulic performance of coastal structures along their lifetime in a context of uncertainty. In this work, a novel methodology for applying a probabilistic approach for non-conventional breakwaters in shallow wate...

The aim of the present paper is to give some preliminary guidelines for the design of recurved parapet wall.The results of the work are carried out by menas of numerical simulations, carried out with OpenFOAM ®. The goal is to describe the influence of the wave period on the confined-crest impact (Castellino et al., 2018). The confined-crest impact...

A new methodology has been defined to calculate three-dimensional loads (forces and moments) and hydraulic stability (sliding and overturning) on concrete caissons all alo ng construction stages of their life cycle, from isolated caissons to the final operation phase. The study of wave loading on the caisson has been simulated using a coupling of t...

In this paper we present a new method for numerically modelling landslide-generatedtsunamis in OpenFOAM® by using a new approach based on the Overset mesh technique. This technique, which is based on the use of two (or more) numerical domains, is new in the coastal engineering field and appears to be extremely powerful to model the interaction betw...

We use a numerical model, already validated for this purpose, to simulate the effect of wave frequency spread on wave transformation and swash amplitudes. Simulations are performed for planar beach slope cases and for offshore wave spectra whose frequency spread changes over realistic values. Results indicate that frequency spread, under normally a...

Historic coastal structures have played a key role in small- to medium-size ports, being the driving force for the local development of coastal communities. Because coastal managers require reliable risk-based analysis of the whole life cycle of these coastal structures, previous lifetimes should be studied. This is a differentiating factor with re...

This study investigates the capacity of a Spartina alterniflora meadow to attenuate waves during storm events based on field observations in the Chesapeake Bay. These observations reveal that environmental conditions including the ratio between water depth and plant height (hr), the ratio between wave height (HS) and water depth, and current direct...

In a time span of over 3,000 years, the function of harbor breakwaters has remained the same (i.e., the energy dissipation), with differences depending on the general breakwater configurations: rubble mound breakwaters or caisson breakwaters. The recent demands of the sea level rise and the intensification of extreme events related to climate chang...

With the aim of better understand and parameterize the physical processes involved in flow-mangrove interaction, wave attenuation and drag forces along a 1:6 scale fringe Rhizophora mangrove forest are studied experimentally. The 26 m long forest is composed by 135 models built reproducing mature Rhizophora mangrove trees with 24 prop roots. Hydrod...

Rubble mound-breakwaters are commonly constructed with a parapet or crown-wall at the crest. The design of these superstructures depends on the expected storm wave load history throughout the service life cycle. In tsunami-prone areas, this design must include tsunami actions since their loads can definitely exceed those of storm waves. However, ts...

In recent years, there has been an increasing interest in modelling floating structures in marine environments. A considerable amount of research has been done in the fields of renewable energy, naval engineering and oil-gas industry. Movable structures like wave energy converters (OWC) or floating offshore wind turbines (FOWT), moored ships or flo...

This paper describes 2-D numerical simulations aiming to reproduce the pressure impulse named confined-crest impact (Castellino et al., 2018), which occurs when a recurved parapet wall and non-breaking wave conditions are interacting. The simulations are carried out by using the IH2VOF and IHFOAM, the latter developed as OpenFOAM additional library...

The hybrid non-conventional breakwaters are innovative coastal structures, which have as a primary function the coastal and harbours protection, but with the important benefit of electricity production, due to their combination with Wave Energy Converters. The most recent example of a non-conventional breakwater is called OBREC, standing for Overto...

Numerical modelling of the interaction of water waves with coastal structures has continuously been among the most relevant challenges in coastal engineering research and practice. During the last years, 3D modelling based on RANS-type equations, has been the dominant methodology to address the mathematical modelling of wave and coastal structure i...

Tsunamis are relatively infrequent but very destructive phenomena that can cause devastating consequences on coastal areas. In view of recent tragic episodes, the scientific community is strengthening their efforts to develop strategies to mitigate the risk of tsunami consequences, specially focused on the potentially affected areas. One of the str...