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Dams are invariably used for multipurpose benefits to the society such as generation of hydropower, irrigation, water supply, flood control, and others, but with associated high risk. As it retains huge amount of water, there is always a risk of formation of breach. There is a need to study the breaching aspects of a dam. In this paper, a hydraulic model named MIKE11 developed by Danish Hydraulic Institute (DHI) is used to carry out simulation of flood resulting from the failure of Indravati multipurpose dam in the Odisha state. Propagation of the flood wave at its downstream reaches is studied, and the consequent inundation map of the downstream submerged areas is prepared. Digital elevation map of the study area is obtained from USGS site and is converted into ARCII with the help of ArcGIS software. Simulations carried out posed a challenge due to the availability of low-resolution topographic data, stiff slope of the channel, obstructions at the downstream side of dam, and other factors.

Outflow facility is a measurement of the ease in which aqueous humor flows out of the anterior chamber through the primary resistance tract of the trabecular meshwork. Tonography is an adapted procedure of tonometry in which intraocular pressure (IOP) is measured before, during and after applying a weight to the eye, yielding an outflow facility value in μL/min/mm Hg. Ocular rigidity, and pseudofacility impact tonography and interpretation of outflow facility measurements. The tonography method has numerous assumptions and limitations, but it remains a key research tool to measure outflow facility and analyze aqueous humor dynamics. Tonography helps understand how IOP is maintained in the healthy eye and how it is altered in disease states such as glaucoma. This review discusses the development, principles and practice of tonography in addition to the instruments used in tonography.

Left ventricular outflow tract and aortic valve anomalies in a biventricular circulation are a heterogeneous group of lesions with resultant obstruction below, at the level of, and above the aortic valve. Valvar aortic stenosis accounts for the majority of left ventricular outflow obstructive lesions with predominance of bicuspid aortic valve disease. Majority of aortic stenosis progresses over time; clinically significant aortic stenosis will need intervention in the neonatal period. Current management strategies are evolving with improved understanding of this heterogeneous condition.

In a turbine, the leakage loss is an important source of turbine aerodynamic loss. In this paper, steady numerical simulations were performed to analyze the flow characteristics in the shroud of a 1.5-stage axial turbine and the interaction between the leakage flow and the mainstream. A spatial loss audit inside shroud was undertaken and the loss in the shroud was assessed. Based on the Liutex method, the vortices in the shroud were identified. The results show that the leakage flow in the shroud could be regarded as a jet process with several parts which are free jet and wall attached jet. The rest part of the shroud was occupied by the vortices and separated flows. There is both inflow and outflow on the interface of outlet cavity and mainstream, accompanied by a series of vortices in the outlet cavity. The loss in the inlet cavity is affected by the leakage flow intensity. The loss in the outlet cavity accounts for the largest part of the loss in the shroud.

The knowledge of the laws governing intense evaporation is important for vacuum technologies, exposure of materials to laser radiation, outflow of a coolant on loss of sealing in the protective envelope of an atomic power plant, and for other applications.

Introduction: We previously examined the relationship between global autoregulation pressure reactivity index (PRx), mean arterial blood pressure (ABP), Resistance to cerebral spinal fluid (CSF) outflow (Rout) and their possible effects on outcome after surgery on 83 shunted patients. In this study, we aimed to quantify the relationship between all parameters that influence Rout, their interaction with the cerebral vasculature, and their role in shunt prognostication.

Variability of the hydrothermodynamic characteristics of the North Atlantic subpolar gyre on multidecadal scale is analyzed using ORA-S3 ocean re-analysis data for the period 1959–2011 and the COREv2 data for the period 1949–2006. It was shown that an increase in the outflow of heat from the ocean to the atmosphere since late 1990s in the Subtropical Atlantic was accompanied by a corresponding decrease in heat loss from the ocean surface in the Subpolar Atlantic. This is consistent with the Gulf Stream meridional displacement to the south in the warm phase of the Atlantic multidecadal oscillation (AMO). In the positive AMO phase, the depth of convective mixing at the Labrador Sea decreases, the sea surface height increases and cyclonicity in the subpolar gyre weakens from January to March. During these months, the response of the subpolar gyre circulation to long-term changes in the intensity of convective mixing at the Labrador Sea occurs with a 5–10 years delay.

This paper proposes a new design of the variable geometry air diffuser for energy-efficient ventilation and air conditioning systems with variable airflow. The device enables to adjust the outflow parameters, and therefore the jet properties (range, expansion angle, decay rate). The kinematic characteristics of the formed jet are studied for different ratios of the inlet and outlet diameters of the air diffuser. In the course of the experiments, the jet axis velocities were registered at different distances from the outflow plane. It was shown that at the jet formation section (x ≤ 0.25 m), the axial velocity first decreases and then increases intensively, which indicates the presence of a rarefaction zone behind the baffle. It was found that the change in the relative jet velocity as a function of the distance to the air diffuser is practically the same for all the considered outflow velocities at a fixed angle of the case petals’ expansion. The change in the velocity coefficient with an increase in the expansion angle of the air diffuser plates was plotted. It was found that for small expansion angles the kinematic coefficient equaled 5.1, which is typical for a compact jet. At angles of 45° and 80° it equaled 3.9 and 2.9, respectively, which is typical for conical and fan jets. Thus, the proposed air diffuser allows adjusting the parameters of the outflow and, accordingly, the kinematic coefficient in a wide range, and can be used for ventilation and air conditioning systems with variable air supply.

Marine megafauna typically include large pelagic sharks, sea turtles, seabirds, and marine mammals. These megafauna are mainly associated with pelagic ecosystems through which they undertake long-distance migration. The Alboran Sea connects the Atlantic Ocean and Mediterranean Sea and is thus a relevant hotspot for marine megafauna. In this area, the overlap between various human activities—such as marine traffic or fisheries on the north and south coasts—and pollution entails the capture or mortality of marine megafauna. We review the main research and findings on marine megafauna in the Alboran Sea and discuss research approaches that could provide suggestions for the effective management of large marine ecosystems.

The Chino Basin in Southern California is part of the Santa Ana River watershed. This chapter describes the groundwater basin itself, which is fed by precipitation runoff from the adjacent mountains and overlying stream channels and contributes outflow to the Santa Ana River. The chapter also describes the river system, including areas upstream and downstream of Chino Basin. Although human activity has altered the natural physical system, especially during the past century, the fundamental elements of the basin’s inflow and outflow, its storage capacity, and its location within the river system and its relationship to the other streams and groundwater basins within the watershed, are essential to understanding the resource management opportunities and constraints of Chino Basin.

Calculation of air distribution in premises is one of the main stages when designing ventilation and air conditioning systems of a building. The microclimate quality and the efficiency of ventilation and air conditioning systems depend on the accuracy and correctness of the calculations. The purpose of this study is to assess the influence of the distance between the inlet and the 45-degree turn on the jet characteristics. The basic geometric and kinematic characteristics of the jet flowing from the opening located at various distances from the 45-degree turn were obtained. The change in the deflection of the outflow angle and the kinematic coefficient of the inlet opening were obtained.

A reinforcement learning algorithm is coupled to a thermal lattice-Boltzmann method to control flow through a two-dimensional heated channel narrowed by a bump. The algorithm is allowed to change the disturbance factor of the bump and receives feedback in terms of the pressure loss and temperature increase between the inflow and outflow region of the channel. It is trained to modify the bump such that both fluid mechanical properties are rated equally important. After a modification, a new simulation is initialized using the modified geometry and the flow field computed in the previous run. The thermal lattice-Boltzmann method is validated for a fully developed isothermal channel flow. After 265 simulations, the trained algorithm predicts an averaged disturbance factor that deviates by less than $$1\%$$ 1 % from the reference solution obtained from 3,400 numerical simulations using a parameter sweep over the disturbance factor. The error is reduced to less than $$0.1\%$$ 0.1 % after 1,450 simulations. A comparison of the temperature, pressure, and streamwise velocity distributions of the reference solution with the solution after 1,450 simulations along the line of the maximum velocity component in streamwise direction shows only negligible differences. The presented method is hence a valid method for avoiding expensive parameter space explorations and promises to be effective in supporting shape optimizations for more complex configurations, e.g., in finding optimal nasal cavity shapes.

In this paper, we propose a nonreflecting outlet boundary condition (NROBC) for particle-based fluid simulation as a combination of inflow/outflow algorithm and periodic boundary condition. We assume to use δ-SPH scheme for weakly compressible flows. In the inflow/outflow algorithm, the domain is divided into four zones: fluid, wall, inflow and outflow zones. The NROBC proposed in this paper inherits the advantage of the periodic boundary condition in the sense that the number of particles is constant. This property contributes to conservation of total mass and insertion of inflow particles without rearranging process. The physical quantities such as density and velocity at the inflow zone are unknown depending on the situation. Our boundary condition supports both cases, prescribed and non-prescribed, and the loss of the accuracy is small even if the quantities are non-prescribed at the inflow zone. In addition, tensile instability is effectively reduced by particle shifting technique. Several simulations are presented to validate and demonstrate the applicability and versatility of the proposed technique. Comparisons between numerical results and analytical solutions are provided with very low Mean Square Error Percent (MSEP) in both test cases.

The evacuation planning problem models the process of shifting residents from emergency areas (sources) to safe places (sinks) as quickly and efficiently as possible. Most of the flow over time models used in the evacuation planning are based on the flow conservation constraints, i.e., the inflow should be equal to the outflow on each node except at the sources and sinks. We investigate the universal maximum flow problem with intermediate storage, i.e., the inflow may be greater than the outflow on intermediate nodes which maximizes the number of evacuees leaving the emergency areas at each point of time. We propose efficient algorithms to solve the problem on two-terminal series-parallel and general networks. We also discuss the solution technique for the problem with arc reversal capability and compare these solutions without and with intermediate storage.

The outflow of the cerebrospinal fluid (CSF) in animals was over the years the subject of detailed analysis. For a long time it was stated that arachnoid granulations of the venous sinuses play a key role in CSF circulation. However, recent studies on this subject have shown that a considerable part of the CSF is drained to the lymphatic vessels. Moreover, disorders in the CSF passage may result in severe central nervous system diseases such as e.g. hydrocephalus. In this paper, we summarize the current knowledge concerning the lymphatic drainage of the CSF in mammals. We present in detail comparative anatomy of different species taking into account cranial and spinal compartment. In addition, we clarified role of the lymphatic vessels in the CSF outflow and the relationship between impairment in this transport and central nervous system diseases. In the author’s opinion knowledge on CSF circulation is still poorly examined and therefore required comment.

Outflow tract PVCs can be accessible in the majority of cases. PVCs that originate in the left ventricular summit may be difficult to target with ablation directly. Ablation in the pulmonary cusp is feasible but should be carefully performed.

A massive landslide of 210 m height occurred in year 2010 at Hunza River near Attabad village, about 100 km upstream of the confluence of Hunza River with Gilgit River. Keeping in view the high storage capacity of this landslide, overflow or piping can washout this landslide mass within a few hours, once the collapse start, with disastrous impacts downstream. Dam Break Analysis has been carried out, using hydrodynamic module of MIKE 11, to predict flood wave arrival time, peak discharge and wave height at Daniyor Bridge upstream of the confluence of River Hunza and River Gilgit. The water levels observed at Daniyor Bridge for years 2011 and 2012 are used for calibration and validation of the routing model, and the results are found to be very satisfactory. Sensitivity analysis is also performed on the model’s main input parameters and their effect on the peak outflow, flood wave arrival time and wave height are studied. The study incorporates computations under six different breach triggering and breach shape scenarios, which include trapezoidal and triangular breach shapes with failure due to either piping phenomenon or overtopping of the dam crest or user-defined breach of the dam. The results of the dam break analysis can be used for the preparation of an Emergency Action Plan for the affected area. The paper presents the details of the project, the model set up and details of the studies carried out.

Rainwater management in urban areas takes into account the needs of both the environment and people. The urbanization process has a dramatic impact on water retention hydrology, leading to increased volumes and outflow rates, filtration losses and subsurface flow. The creation of paved surfaces results in drainage of rainwater into a drainage network, which contributes to the reduction of natural filtration. The essence of the solution to urban hydrology lies in finding an acceptable compromise as an alternative solution for the drainage of rainwater from a territory. The subject of the research described in this chapter is a solution to water infiltration from surface runoff and a comparison of the results obtained from field measurements, laboratory analyses and numerical calculations. Such research is necessary mainly due to insufficient information in the technical standards of the Slovak Republic in the field of infiltration systems and rainwater infiltration, as well as solutions to them.

Imaging aqueous outflow is paramount to our understanding of normal ocular function and homeostasis, but presents a number of technical challenges. The minuscule rate of production and outflow (about 2.5 μL/min) of the transparent colorless aqueous humor, the microscopic caliber of outflow pores and channels, and the light-scattering properties of limbal tissue complicate effective imaging. The techniques in this chapter summarize the best methods of their time, going back nearly 200 years, which led to the discovery of Schlemm’s canal and downstream outflow tract structures. We discuss their high-definition, three-dimensional reconstruction and quantification of total as well as focal outflow. A better understanding of structure and resulting function, both through in vivo experiments and flow simulation, is needed.

At the National Technical University “Kharkiv Polytechnical Institute”, an experimental pulse compression detonation (PCD) system was developed to operate on propane-air mixtures while addressing potential issues with regards to efficiency, ignitability of the gas, and the critical tube diameter for detonation. In this PCD system, the reactive gas was pre-compressed within the detonation tube, before ignition. The resulting mixture was found easier to ignite, and the transition to detonation within the tube was much more reliable and consistent. To gain further insight, and to investigate the effect of pressure gradient on the strength/velocity of outflow products and the overall thermodynamic cycle, a two-stage modelling procedure was adopted. First, a 3D inert simulation of the compression process of the PCD system was conducted using ANSYS. The resulting pressure and density profiles within the detonation tube were then prescribed as initial conditions for a 2D detonation stroke and outflow simulation. For this stage, the Compressible Linear Eddy Model for Large Eddy Simulation (CLEM-LES) framework adopted. For the PCD system, it was found that higher peak pressures were obtained at the outflow location of the tube when compared to a detonation tube filled initially at constant pressure equal to the ambient condition. As a result, the higher thermal efficiency of the detonation cycle may be achieved. However, it was found that the outflow products were under expanded, which may adversely affect the generated impulse. Therefore, the use of nozzles should be investigated in future work as part of the PCD system proposed here.

This chapter presents preliminary results of a 2D antiparallel magnetic reconnection simulation performed with the ViDA code introduced in Chap. 8. Firstly, the magnetic reconnection signatures are presented. Then, the chapter focuses on the evaluation of the contribution of the terms of Ohm’s law in the EDR. It is found that the electron inertia term, and in particular the term which is proportional to the temporal variation of the current density plays a role in sustaining the reconnection electric field. This contribution is not limited to an electron scale region around the X-point but it extends to the ion scales in the outflow direction. This feature can depend on the artificially low mass ratio adopted here.

This article proposes a method for extracting hot water from a well drilled until the point where temperature exceeds the boiling point of water at a given depth. Core of this method lies on the physical mechanism of the eruption of a natural geyser. It bases on the cold water erupting from the well after entering inside from the surface of the earth due to the gas liquid imbalance (hereafter GLI). This column of water rises up due to the mutual movement between contacting liquid and gas by the pressure of the gas applied on it. The paper researches the physical conditions under which spontaneous outflow of hot water from the well to the surface begins. Described method of extraction of underground heat allows to eliminate the cost of energy required for the operation of circulating pumps of traditional geothermal power plants, since the heated water will be thrown out to the outside, obeying the GLI mechanism. Thus, this method can be considered as an environmentally friendly and significantly reduces the cost of extracting heated water from the well.

The use of RWHS not only protects natural water resources, brings financial benefits resulting from the lower consumption of tap water, but also by reducing the outflow of water from the catchment, it also has a positive effect on the functioning of sewerage systems. Taking the above into account, the research was conducted to determine the impact of RWHS application on the volume of rainwater outflow from the catchment and on the functioning of the sewage system. A real urban catchment was selected for the study, for which a hydrodynamic model was developed in the stormwater management Model (SWMM).

The issues of ensuring the tightness of sealing joints are considered. It is indicated that to calculate the tightness at the design stage, it is necessary to know the regime of the outflow of the medium being sealed, which is determined by the Reynolds number. It is shown that the Reynolds number is determined by the ratio of the linear mass flow rate through the sealing joint to the dynamic viscosity of the sealed medium. Dependencies of the relative contact area, the density of gaps in the joint, and the probability of medium flow from the dimensionless force elastic-geometric parameter fq should be determined taking into account the mutual influence of asperities of the rough surface. Said contact characteristics determine the functional of the permeability Cu which characterizes the sealing capacity of the sealing joint. Their role in various periods of loading of a sealing joint by a dimensionless load is shown.

River basin yield is influenced by rainfall and rainfall is influenced by various global climatic inputs. In this study, the prediction of river basin scale yield of ‘Upper Bhima River basin’ from the Maharashtra State of India has been attempted. The global climatic inputs, namely El Nino-Southern Oscillation (ENSO) index, and Equatorial Indian Ocean Oscillation (EQUINOO) index were used for the prediction. The Artificial Neural Network (ANN) tool has been used through Matlab for this purpose. Upper Bhima river basin consists of many dams and reservoirs harnessing water for irrigation, hydropower and domestic uses. Inflow, outflow, water use and losses of all reservoirs are taken into consideration while calculating actual yield Upper Bhima River Basin. Four combinations of input variables for predicting reservoir yield were tested to arrive at the best input variable combination for better predictions. From the analysis, it was found that models developed using ANN establish reasonably good relationships between climate variables and basin scale yields The best combination of ENSO and EQUINOO gave correlation coefficient r = 0.712 between observed river basin yield and predicted river basin yield, which appears attractive for such a complex system.

Hydrological functions of lakes in shaping the runoff of rivers that drain them were discussed on the basis of data from the literature. The discussion indicates the role of lakes in initiating river runoff, their role in water storage and runoff equalization of a river flowing through or out of the lake, as well as the role in shaping the runoff capacity of the river: its increase due to underground water drainage by the lake basin or decrease as a result of lake waters supplying the underground water. It was pointed out that there are lakes which regardless of the character of the hydrological year (wet, average, dry) constantly increase the runoff of the river which flows through them by incorporating into it the water which they receive from underground drainage. There are also lakes that constantly feed underground waters with their waters, which reduces the runoff of rivers flowing from them. There is also a group of lakes which, depending on the level of the storage of the basin, conditioned by the water content of the hydrological year, either drain underground waters and increase river runoff or aliment them thus reducing river runoff. The above hydrological functions of lakes were discussed on the example of outflow and flow-through lakes of northern Poland.

The rapid wall erosion of the settings of pump elements occurs during pumping of two-phase mediums, in the hydraulic and pneumatic transport systems. In these circumstances, it is reasonable to use the jet technology in general and the vortex chamber superchargers in particular. The vortex chamber superchargers have the best, compared with other jet superchargers, energy efficiency indicators during pumping of bulk materials. The purpose of the article is to study the wall erosion of the vortex chamber. The mathematical modeling of the flow is carried out by solving the averaged Reynolds equations using a SST turbulence model corrected. Simultaneously with the hydrodynamic calculations the trajectories of abrasive material solid particles were calculated. Finney’s model was used to model the wall erosion. It is found that for all values of the flow rates and, accordingly, the concentration of solid particles, a uniform wear of the vortex chamber is observed. To ensure the durability of superchargers it is necessary to increase the thickness of the chamber’s walls. In the process of wear, the ratio of diameters of the inflow channels to the diameter of the vortex chamber will increase. It affects the energy characteristics of the supercharger: the efficiency, the amount of medium at the outflow of the device, the vacuum value near the axis. By setting minimum acceptable parameters it is possible to predict the wear of the chamber and calculate the resource of the supercharger without the use of expensive experimental investigations.

One of the longest-standing theoretical questions aiming to characterize the main outflow driving mechanisms is whether flows are driven in a momentum or energy-conserving manner. We here present a set of consistent and complete measurements of both momentum and energy for jets and outflows driven from seven protostars in the NGC 1333 star-forming region. While our observations clearly point toward an energy conservation mechanism, conservation of momentum can still be valid alternative given that jets become detectable through emission in shock interfaces, while most of the mass along the jet propagation axis is not excited and therefore remains “dark”, that is, unobserved. Recent episodic accretion/ejection models of a nested jet/outflow configuration, where the jet morphology is linked to the episodic accretion and the large scale outflow carries the bulk of the momentum from the system, may also provide convincing solutions to the observed deficit between the jet and outflow momentum.

Recent magnetohydrodynamic (MHD) simulations are presented investigating the launching of jets from accretion disks, that is (i) the internal disk structural evolution that leads to different launching conditions over time, (ii) a new, fundamental interrelation between the disk magnetization at the launching point and the asymptotic outflow properties, (iii) the launching of jets driven by a self-generated disk dynamo magnetic field, and (iv) simulations of jets from orbiting jet sources.

The aqueous humor outflow (AHO) tract is the pathway by which fluid travels from the eye’s anterior chamber to drain into the venous circulation. This tract plays an important role in the regulation of eye pressure and is likely key in the pathogenesis of glaucoma. As such, the outflow tract is a target for alteration by medical and surgical treatment approaches. To understand this pathway’s anatomy and physiology, numerous structural and functional studies have been conducted. While the ability to conduct such studies has advanced along with modern imaging approaches, many challenges to accurately assessing its structure and function remain.

The atmosphere is a forced-dissipative system. It has to export more entropy than it imports in a steady state. Therefore, the entropy inflow and outflow have to be distinguished from the internal entropy production, which has to be positive in the mean on long timescales. This principle does not only hold for the whole atmosphere, but also for subsystems like individual grid boxes in a numerical model. However, the constraint of positive internal entropy production was not taken into account when developing contemporary subgrid-scale parameterization schemes for atmospheric models. Some of these schemes suit automatically into this framework; some do not. This article discusses the current understanding and scientific discussion of this topic and illustrates possible future development paths.

Observations and simulations have joined efforts to answer many questions raised by the unexpected behavior detected in Young Stellar Objects (YSOs). Classical T Tauri stars (CTTS) are a particular case of YSOs. These objects are interacting with their disks not only through accretion, but also through outflow processes. In this work, we will reproduce the accretion and outflow environments of RY Tau through magneto-hydrodynamical (MHD) simulations constrained by observations. Firstly, stellar activity parameters will be derived from permitted and forbidden lines in the optical spectrum of the CTTS. Secondly, we will use those parameters to adjust the simulations. In this work we reached two possible behaviors, either a steady configuration is achieved in few stellar rotations or a more turbulent one with magnetospheric ejections.

Supernovae and astrophysical jets are two of the most energetic and intriguing objects in the universe. An interaction between these two extreme phenomena is believed to be present in the case of the W50-SS433 system: a jet launched from the microquasar SS433 (an X-ray binary) located inside a supernova remnant, W50. Observations have revealed a unique morphology of the remnant, attributed to the presence of the jet. Motivated by these studies, we performed full 3D relativistic hydrodynamic simulations to better capture the interaction between the remnant and the jet. The output was used to create emission maps by post-processing them with a radiative transfer code. We verify again (in 3D) that the stratification of the ambient medium is important to reproduce the asymmetric shape of W50. The full precession of the jet is now implemented; its effect is important before collimation but not evident compared to a straight outflow on larger scales. Radio maps quantitatively agree with actual observations of W50, with further improvements needed to correctly capture the intensity distribution of the remnant.

The accurate prediction of crowd flow is of great significance for urban traffic management and public safety. Its key challenge lies in how to model the complex non-linear spatial-temporal dependencies and other external factors such as holidays and weather conditions. In this paper, we propose a novel deep-learning-based approach to address this problem, called Spatial-Temporal Densely Connected Networks (ST-DCN), which is able to predict both inflow and outflow of crowds in every region of a city. Specifically, ST-DCN consists of three parts: spatial module, temporal module and external module. The spatial module is designed with a densely connected convolutional structure to capture the spatial dependencies at a citywide level. The temporal module is composed of ConvLSTM units to learn long-term temporal dependencies. We propose an external module consisting of fully connected layers for modeling the external factors. Then the outputs of these three modules are merged to predict the final crowd flow in each region. ST-DCN can alleviate the vanishing-gradient problem and strengthen the propagation of spatial features in very deep network. In addition, the spatial features structure can be maintained throughout the network to avoid losing implied spatial information of crowd flow. Experimental results on two real-world datasets demonstrate that ST-DCN achieves significant improvements over the state-of-the-art methods.

The Douro is one of the largest rivers of the Iberian Peninsula, representing the most important buoyancy source into the Atlantic Ocean on the northwestern Portuguese coast. The main goal of this study is to contribute to the knowledge of physical processes associated with the propagation of the Douro River plume. The general patterns of dispersion in the ocean and how the plume change hydrography and coastal circulation were evaluated, considering the main drivers involved: river discharge and wind. Coastal models were implemented to characterize the propagation of the plume, its dynamics, and its impact on coastal circulation. Different numerical scenarios of wind and river discharge were analyzed. The estuarine outflow is sufficient to generate a northward coastal current without wind under moderate-to-high river discharge conditions. Under easterly winds, the propagation pattern is similar to the no wind forcing, with a northward current speed increasing. A southward coastal current is generated only by strong westerly winds. Under upwelling-favorable (northerly) winds, the plume extends offshore with tilting towards the southwest. Southerly winds increase the velocity of the northward current, being the merging of the Douro and Minho estuarine plumes a likely consequence.

This paper studies the interaction between downburst outflows and the background atmospheric boundary layer (ABL) winds close to the surface. Downburst is a buoyancy-driven downdraft of cold air that emerges from cumuliform clouds and results in a vigorous starburst outflows upon reaching the surface. Currently, there are neither satisfactory analytical models nor experimental results on the highly complex interaction between these two wind systems. One of the advanced modes of the WindEEE Dome operation, at Western University in Canada, enables the simultaneous generation of downbursts and ABL winds. In accordance with the WindEEE Dome capabilities, an experiment is designed to address this long-standing question on the relationship between ABL winds and downbursts. This paper shows the interaction between downburst and ABL winds for seven azimuthal positions in respect to the incoming ABL wind direction and six heights. The results show that the traditional approach of adding ABL winds to downburst outflow as either vector or algebraic sum is inaccurate for all heights and azimuth angles. A new empirical relationship between downbursts with and without ABL winds is presented herein.