Incoming Flow Research Articles

Energy harvesting from transverse galloping using a two-degree-of-freedom flow energy harvester

Abstract A two degree-of-freedom (2-DOF) galloping piezoelectric energy harvesting system where both oscillators are excited by the incoming flow is studied in this paper. A coupled lumped-parameter model is developed to simulate the electro-fluid-structural coupling behaviour assuming a quasi-steady aerodynamic flow field. The differential equations governing the dynamics of the lumped system are converted into nonlinear algebraic equations employing the harmonic balance method (HBM) and then solved using Newton’s method. The approximate analytical solutions are compared to the solutions obtained by numerical integration, and the results agree, both qualitatively and quantitatively. The solutions were subsequently used to investigate the effects of the bluff body dimension, mechanical, electrical, aerodynamic, and electromechanical parameters on the performance of the harvester and to illustrate how to optimise some of these parameters to reduce the cut-in wind speed and maximise the power output of the energy harvester. It will be shown that the energy harvesting performance could be significantly improved by introducing piezoelectric transducers on both oscillators and including both masses in the incoming flow. A comparative study between the proposed 2-DOF flow energy harvesting system, a single-degree-of-freedom (SDOF) galloping piezoelectric energy harvester (GPEH), and other configurations of 2-DOF GPEH shows that the present 2-DOF GPEH generates the largest power peak.

Impact of Political Instability on Tourism in West Bengal.

This study aimed to investigate the effects of political instability on tourism-related business performance, incoming tourist flows in West Bengal, and overall tourism-based earnings. The nonlinear effects of political risk and economic growth on tourism receipts are examined in this research. Nevertheless, the secondary data that is now accessible with the unobserved component model technique detection only provides a broad picture of the issue. Experts such as managers of lodging establishments, staff members of local tourism development offices, and tourism researchers were interviewed as a result. Expert interviews exposed West Bengal's tourism industry's prospects, challenges, and potential developments in the face of the region's five years of political unrest. The findings confirm earlier research showing that, in the near run, political unrest lowers tourism. However, the long-term viewpoint has yielded various results from the expert interviews with main province cities. Political instability benefits cities with developed tourism businesses that are located outside of crisis areas. Places that relied on visitors from the countries or continents like Europe, Germany, China, USA are mostly affected. The political unrest in eastern West Bengal did not significantly affect cities with low levels of tourism development.

Investigation of airflow thermal ice melting process under various flight conditions

The challenge of preventing and removing ice from exposed regions of aircraft is a significant engineering concern. Understanding the melting process of ice due to aerodynamic heating during flight is essential for developing UAV flight strategies in icy conditions. This paper analyzes the heat transfer mechanisms involved in airflow over ice and introduces a theoretical model to estimate the ice melting rate, using principles of turbulent heat transfer at the stagnation point. The study also discusses the impact of environmental conditions on ice melting rates. Findings indicate that the melting speed of the ice surface exhibits a negative linear correlation with the initial temperature of the ice, whereas it shows a nonlinear correlation with airflow velocity and total temperature of the incoming flow. Lower airflow velocity or total temperature of the incoming flow enhances the sensitivity of ice melting speed to changes. Additionally, lower ice density results in a higher melting speed, showing an exponential relationship with factors like average droplet diameter, airflow velocity, and airfoil leading edge diameter in the cloud field during icing. Experiments conducted using a small jet test bench and an icing wind tunnel confirmed the impact of varying conditions on ice melting rates. The deviation between experimental results and theoretical predictions was under 5 %. These conclusions offer valuable insights for flight safety planning of unprotected iced aircraft in challenging environments.

Remittance Inflow, Investment, and Economic Growth in Africa amidst COVID-19 Pandemic

Africa has fared well in the aspect of remittance receipts in recent years; however, the region recorded a decline in remittances amid the COVID-19 pandemic which constrained the circular flow of income significantly and ultimately economic growth. In view of this, this study investigates the economic effects of remittance inflows and investment on economic growth in Africa amid COVID-19 pandemic using a panel of 48 economies and estimated with pooled OLS and two-step system GMM. The study employed two distinct approaches for estimation; pre-COVID-19 (2010–2019) and amid COVID-19 (2010–2023). The results indicate that the behavior of remittances, investment and economic growth in Africa is not significantly different between pre-COVID-19 and amid COVID-19. That is, remittances remain a significant economic growth catalyst in Africa whereas investment is not (though with growth effect potential). Overall, the study concludes that African economic policy stakeholders and other relevant policy authorities should sustain the current remittance and labor policy frameworks with possible fine-tuning where applicable while doubling their investment efforts especially in productive sectors of the economy.

Research on the aerodynamic characteristics of dragonfly leading edge.

Dragonflies are some of the most stable and maneuverable flying organisms. To explore the mechanism of how dragonfly leading edges enhance flight lift, this article conducts a detailed study on the leading edge veins and the microstructures on them of dragonfly wings. Observations have discovered the special leading edge vein and the regularly distributed microstructures on the leading edge vein. A biomimetic model has been established, and computational fluid dynamics (CFD) simulation analysis has been conducted on the biomimetic model. The analysis explores the effects of microstructure characteristics, distribution patterns, and positions on the aerodynamic characteristics of dragonfly gliding. The analysis shows that the leading edge structure influences the incoming flow, simultaneously promotes the formation of the leading edge vortex (LEV), and increases the lift-to-drag ratio by up to 4%. A wing prototype featuring biomimetic microstructures is subsequently fabricated and tested in wind tunnel experiments. Compared with a control group without leading edge structures, the airflow passing through the biomimetic structures is influenced by the shape and arrangement of these structures. The smoother transition of the leading edge vein's shape facilitates the flow of air. The microstructures primarily filter and accelerate the airflow. The spacing of the microstructures affects the stability of the airflow, thereby influencing aerodynamic performance. Additionally, the middle-row arrangement of microstructures is more beneficial for gliding conditions, while the upper-row arrangement is more advantageous for flapping conditions. These findings enhance our understanding of insect wings and advance micro aerial vehicle applications. RESEARCH HIGHLIGHTS: This study observed the leading-edge veins and microstructures of dragonfly wings in detail. Using a biomimetic model and computational fluid dynamics (CFD) simulations, it was found that these leading-edge structures promote the formation of leading-edge vortices (LEV), increasing the lift-to-drag ratio by up to 4%. Wind tunnel experiments demonstrated that wings with biomimetic microstructures significantly improved airflow smoothness and lift compared with control wings. Additionally, the arrangement of microstructures greatly affects airflow stability and aerodynamic performance, with middle-row arrangements being more beneficial for gliding and upper-row arrangements for flapping conditions. These findings enhance our understanding of insect wings and provide innovative guidance for designing efficient micro aerial vehicles.

VARIABLE ASSESSMENT OF THE TRANSPORT AND LOGISTICS SCHEME FOR THE DISTRIBUTION OF GOODS TO THE TRADE NETWORK

The distribution of goods to the trade network is a complex process that requires a careful approach to determining the hierarchical structure of the interaction of participants in the logistics chain and planning their activities. An essential element of this process is choosing the configuration of the transport and logistics scheme, which ensures efficient and timely delivery of goods to the trade network. In this study, we propose to carry out a variable assessment of the efficiency of the distribution of goods according to basic schemes on the ground of taking into account a set of factors, such as the distance of transportation, volume of cargo, delivery terms, specific costs for transportation and storage of freight, the impact of changes in the speed of movement and the time of cargo operations. It makes it possible to present the choice of a rational transport and logistics scheme in the form of an optimisation process to make it more flexible and adaptable to the changing conditions that characterise the current distribution of goods. The article aims to establish a rational structure for determining the efficiency of the delivery of goods to the trade network based on evaluating a sensible version of the transport and logistics scheme, which ensures the conditions for implementing technological operations in time. The methodological basis for establishing a rational version of the transport and logistics scheme is a developed structural model of the influence of input parameters on the total costs and timeliness of delivery of a batch of goods to the trade network. Such a research model describes the functional relationship between incoming information flows about the volumes of orders for the delivery of goods, the nature of changes in the parameters of cars in motion and under loading-unloading, information about the structure of the available car fleet, and the characteristics of the communication network and the controlling influences represented by the choice of a rational total of trunk and delivery routes. Designating a logical sequence of communication between these flows enables determining the value of the components of the efficiency criterion of the transport and logistics delivery system. We established that the transport and logistics scheme of delivery is the basis for the development of transportation routes and the organisation of the functioning of warehouse distribution complexes. The developed structure for evaluating the efficiency of the delivery of goods to the trade network allows for determining the core conditions of activity of the logistics chain participants and specifying a set of technical, operational, and economic indicators of their work. Accounting for the time parameters of the transport and logistics chain enables taking into account the influence of fluctuations in the high-speed mode of movement and idle time at loading and unloading points. The developed models for estimating the time parameters of cargo delivery facilitate efficient planning of the transportation routes and determine the rational time for delivery of each consignment. All local models work in a complex with the general structure of evaluating the efficiency of goods delivery and ensuring a more efficient and transparent management of logistics processes. Their use allows logistics companies to reduce delivery costs, improve the quality of customer service, and increase the competitiveness of the trading network in the market. Keywords: delivery, product, trade network, delivery chain, logistics system.

Dynamics of a falling plate at low Reynolds numbers

Free-falling of objects in fluids is universal in nature and engineering. The falling styles of the falling object are affected by the properties of both the object and the fluid. Based on the assumption that the final state of a free-falling object at low Reynolds numbers is stable and equivalent to that of a fixed object with incoming flow, we utilize the results for the fixed plate to interpolate and obtain the state of the falling plate. It is found that the plate would exhibit multiple stable falling solutions. The number of stable falling solutions is dependent on the location of the gravity center of the plate. The distribution of the multi-solution region is affected by both Archimedes number (Ar) and the density ratio (m*). The results of the actual fall of the plate do not always agree with those obtained by the static interpolation method due to the fact that the fall of the plate is a dynamic process. We simulate the falling behaviors of plates whose center of gravity is located in the multi-solution region for different initial release angles θ0. According to the falling behaviors of the plate, there are four regions that are observed and denoted in the multi-solution region: (1) single stable region; (2) bistable region; (3) single stable and fluttering region; and (4) bistable and fluttering region. The effects of Ar,m*, and the dimensionless moment of inertia I* of the plate on the distribution of the four regions are evaluated.

A two-cell vortex model

A two-cell vortex solution to the Navier–Stokes equations is derived in this article. The theoretical analysis provides expressions for the velocity components, vorticity, and pressure distributions of the two-cell vortex flow. A key feature of this new modeling approach is the presence of a “vortex eye” region, which is absent in classical single-cell vortex models. The derived tangential velocity profile is kept general, allowing for the recovery of the single-cell profile as a special case. The model parameters are constrained by the boundary conditions inherent to two-cell vortices. The model explicitly demonstrates that the two-cell vortex flow exhibits two regions of recirculating flow structures in the meridional plane. The analysis shows that near the vortex core, fluid descends from above and diverges outward. This downward flow meets the incoming flow from the vortex's outer region at a distance known as the “eye-wall” radius. The merging of these two streams results in an upward deflection, generating the two-cell fluid motion. Unlike in single-cell vortices, where vorticity reaches its maximum at the vortex center, the present results indicate that in two-cell vortices, the vorticity peaks at the eye-wall radius.

ON THE METHODOLOGY OF EXPERIMENTAL RESEARCH FEATURES OF THE FLOW-PLUG INTERACTION WITH AN INCOMING FLOW OF LIQUID

ON THE METHODOLOGY OF EXPERIMENTAL RESEARCH FEATURES OF THE FLOW-PLUG INTERACTION WITH AN INCOMING FLOW OF LIQUID

An exact analytical solution for the weakly magnetized flow around an axially symmetric paraboloid, with application to magnetosphere models

Rotationally symmetric bodies with longitudinal cross sections of parabolic shape are frequently used to model astrophysical objects, such as magnetospheres and other blunt objects, immersed in interplanetary or interstellar gas or plasma flows. We discuss a simple formula for the potential flow of an incompressible fluid around an elliptic paraboloid whose axis of symmetry coincides with the direction of incoming flow. Prescribing this flow, we derive an exact analytical solution to the induction equation of ideal magnetohydrodynamics for the case of an initially homogeneous magnetic field of arbitrary orientation being passively advected in this flow. Our solution procedure employs Euler potentials and Cauchy's integral formalism based on the flow's stream function and isochrones. Furthermore, we use a particular renormalization procedure that allows us to generate more general analytical expressions modeling the deformations experienced by arbitrary scalar or vector-valued fields embedded in the flow as they are advected first toward and then past the parabolic obstacle. Finally, both the velocity field and the magnetic field embedded therein are generalized from incompressible to mildly compressible flow, where the associated density distribution is found from Bernoulli's principle.

Prediction model for self-starting of hypersonic inlets with soft critical unstart mode

The acceleration self-starting performance of hypersonic inlets is of critical importance for the stable operation of scramjet engines. The occurrence of soft unstart during the transition from hard unstart to start is an important flow state that has yet to be fully elucidated. The stability mechanism and corresponding self-starting characteristics of soft unstart remain poorly understood, and there is a pressing need for detailed modeling research in this area. This paper presents a rapid prediction model for the self-starting Mach number of two-dimensional hypersonic inlets with soft critical unstart mode, fully considering the influence of various geometric parameters and Reynolds number in the internal contraction section, and achieving a quantitative analysis of the two-dimensional soft unstart critical flow field. Given the incoming flow conditions and the inlet geometry, the prediction model is capable of accurately representing the actual viscous unstart flow field. It can fully map the unstart separation bubble and its surrounding critical wave structures, and calculate the minimum pressure rise required to maintain the current scale of the main separation bubble and the pressure rise exerted on the unstart separation bubble by the current actual flow field structure. Comparing the relative magnitude of these two pressures determines whether the inlet can transition from soft unstart to start. The proposed prediction model was validated using results from unsteady numerical simulations. The predicted results align well with the simulation results and are significantly better than previous prediction methods.

Effect of Local Heat Supply into Supersonic Incoming Flow Ahead of Thin Body with Disk on Intensity of Weak Far-Field Shock Waves

Effect of Local Heat Supply into Supersonic Incoming Flow Ahead of Thin Body with Disk on Intensity of Weak Far-Field Shock Waves

Numerical investigation on the ventilated supercavitating model with propeller

To achieve stable and continuous supercavitating flow over underwater vehicles, artificial ventilation is implemented, particularly effective at lower speeds. Previous research on supercavitation primarily focused on analyzing ventilated supercavitating flow with various cavitator types and/or ventilation rates. In this investigation, we examine the behavior of ventilated supercavitating flow over an axisymmetric model featuring both a disk cavitator and a Postdam propeller placed at the bow. Utilizing the Large Eddy Simulation turbulence model, Volume of Fluid method, and Kunz cavitation model, our simulation aims to capture the cavitating flow around the propeller and the ventilated supercavitating flow over the model. Validation of our numerical methods is achieved by comparing our results with experimental data of a ventilated model by Chung and Cho [“Ventilated supercavitation around a moving body in a still fluid: Observation and drag measurement,” J. Fluid Mech. 854, 367–419 (2018)] and the cavitating Postdam propeller by SVA Postdam [S. Potsdam, “PPTC smp'11 Workshop,” in Proceedings of the Workshop on Cavitation and Propeller Performance (2011)]. The results show that with a rotating propeller at the bow of the supercavitating model, the cavitating flow extends and stabilizes compared to configurations utilizing a traditional disk cavitator. The presence of the propeller accelerates the formation of supercavitating flow at a consistent incoming flow speed. Additionally, coupling the propeller with the disk cavitator results in significant increases in propeller thrust, torque, and efficiency. While there is an observed rise in model drag, the impact is not substantial.

Determinants of rural households’ food security status in South Africa: lessons from covid-19 social relief grant recipients in NIDS-CRAM wave 5

The world experienced an unprecedented health shock (COVID-19) which caught everyone by surprise, and destabilized many sectors, especially the agri-food sector. This unpleasant situation caused upset in the food production and distribution chain, and continues to threaten the attainment of Sustainable Development Goal 2 which underscores zero hunger in society. Many people in South Africa were disproportionately affected with severe consequences on their livelihood activities, food security status, health status, and general welfare conditions; and as a result, social relief intervention was put in place or expanded. This study examined the factors influencing rural households’ food security status among the recipients of social relief grants in rural areas of South Africa. The study used a secondary dataset from Wave 5 of National Income Dynamics Study - Coronavirus Rapid Mobile Survey (NIDS-CRAM). The research applied descriptive statistics to describe the respondents’ socio-economic characteristics, and pattern of income flow. Food Insecurity Access Scale was employed to investigate the respondents’ food security status, while multinomial logistic regression was used to explore the determinants of food security. The results showed that the majority of the respondents were black (99%), female-headed (54.15%), dwelling in flats (74.01%), with secondary education (88.6%), and heavily dependent on government grants (58.61%). Also, most households were food secure (71.69%) during the pandemic. Moreover, households headed by men were more food secure (62.84%) compared to the ones headed by the female counterparts (37.08). Multinomial regression estimates revealed that formal education (p<0.1), employment status (p<0.05), dwelling type (p<0.01), as well as household size (p<0.01) significantly determined rural households’ food security status. The study concluded that social relief grants significantly reduced the food insecurity situation among the rural households in South Africa, and recommended that the government should ensure the continuation of the social relief of distress grant to the vulnerable people who are mostly domiciled in the rural areas, especially women who are disproportionately affected by these health shocks. Key words: Covid-19, social grant, rural households, food security, South Africa

Noise and flow characteristics of variable backwards- and forward-facing steps and gaps in laminar boundary layer

The noise and flow characteristics of combined backwards-facing and forward-facing steps (BFS and FFS) are experimentally investigated in an acoustic wind tunnel using a far-field microphone array and Particle Image Velocimetry (PIV), respectively. The step models considered have a step height H of 10∼40 mm and a step gap L of 10∼100 mm, and the Reynolds number is ( Re H=) 2.1 × 105∼1.1 × 106. The incoming flow boundary layer is laminar, and the step height is approximately 3∼28 of the boundary layer thickness. The results show that the noise is closely related to the step type, step height H and the gap L. In the step-only configuration, the BFS noise does not vary with the step height H 1 and is much lower than the FFS noise, of which the sound pressure level depends on U 0 5.8∼ U 0 6.2 within the height range H 2. As for the combined step model (BFS&FFS), the noise spectrum changes significantly with the step heights and gaps. When H 1> H 2, the noise spectrum resembles the BFS-only due to the flow shield of the FFS from the upstream BFS. When H 1< H 2, the noise spectrum is dominated by the FFS, especially at higher H 2 or longer gap L due to more face area of the FFS exposed to the incoming flow. As H 1= H 2, the noise resembles the BFS in the low-frequency range and the FFS at high frequencies, respectively. Generally, the step-only and BFS&FFS have broadband noise characteristics, except when the ratio L/H is small, the noise spectrum has the characteristics of a typical cavity dominated by tonal peaks.

Constructal design of cross‐flow heat exchanger with concave/convex fins

AbstractA contractual design of cross‐flow heat exchanger with concave/convex fins under fixed pressure drop is presented in this paper. An array of heated concave and convex fins are placed in a fixed area, and they are cooled by incoming cross flow, which is moving towards the fins due to constant pressure drop. The distances from fin to fin, the fin base, and the fin surface curvature (concave and convex) are free to morph and are constrained by the fin length and the height of cross flow. Bejan's number ranges from 105 to 107. The ratio of fin base‐to‐fin length is changed from 0.1 to 0.3. The dimensionless mass, momentum, and energy equations for two‐dimensional, steady, and incompressible flow are solved based on the finite volume numerical method. Also, the scale analysis method is used to compare heat transfer densities from concave and convex fins. The numerical results showed that the maximal convective heat transfer density for convex fins is higher than that of the concave fins for all Bejan numbers. The augmentations in the maximal heat transfer density are 2.1% at Be = 105, 4% at Be = 106, and 12.5% at Be = 107. Also, this is confirmed by the scale analysis method.

Transition of the flow type in the supersonic cavity controlled by the wall temperature

The wall temperature of the high-speed aircraft increases quickly under hypersonic/supersonic incoming flow, which will cause a significant change in the flow structure. To study the transition of the flow type in the supersonic cavity controlled by the wall temperature, numerical simulations are conducted. The cavity length-to-depth ratio (L/D) is varied from 10 to 15, and the wall temperature ranges from 300 K to 1300 K. The results indicate that the type of cavity flow with an L/D ratio of 13 transforms from a closed cavity flow to a transitional cavity flow, when the temperature reaches approximately 775 K. And the transitional temperature rises with the elevated total temperature of the incoming flow. Furthermore, the mechanism of the cavity flow change with wall temperature could be the competition between the recirculation zone and the shear layer in the cavity. The rising pressure with higher wall temperature in the recirculation zone weakens the downward development of the cavity shear layer, preventing it from hitting the cavity floor. As a result, the mass exchange of cavity lip surface, pressure distribution, total pressure recovery coefficient, and heat transfer distribution in the supersonic cavity change dramatically. The critical wall temperature also affected by the sidewall effects and the inflow Mach number.

Numerical simulation of the primary breakup of fuel jet with incoming positive velocity gradient

To study the breakup process of fuel jets in air crossflow with a positive velocity gradient, the Volume of Fluid (VOF) method and adaptive grid technology are combined to simulate the two-phase flow of gas and liquid. A comparative analysis is conducted on the breakup and corresponding flow characteristics of direct fuel jets under uniform and positive velocity gradient airflow. The simulation results demonstrate that the morphological changes of the fuel column are caused by factors such as gas-liquid shear and asymmetric airflow vortices. The fuel jet undergoes primary breakup, which mainly contains columnar and surface breakup. The columnar breakup is dominated by Rayleigh-Taylor (R-T) instability, while the surface breakup is dominated by Kelvin-Helmholtz (K-H) instability. Compared with uniform flow, the expansion angle in the positive velocity gradient incoming flow increases by an average of 9.2%, and the wavelength of the surface wave increases by an average of 34%.

The artisanal octopus fishery in Mauritania: A lucrative fishery in decline

The octopus fishery is important for the socioeconomic development of Mauritania. However, in recent times the fishery has been declining. To enhance sustainable octopus management and tap maximum economic benefits, we analysed catches and flow of artisanal octopus fishery, fishing effort, employment, and income of octopus fishers. We used data provided by the Artisanal and Coastal Fisheries Monitoring System database collected along the coastline by the Mauritanian Institute of Oceanographic Research and Fisheries surveyors. The data on the operating costs of pirogues came from one-off surveys carried out by the Laboratory of Social and Economic Studies. Our findings show that octopus production increased from 14 thousand tonnes in 2006 to 33 thousand tonnes in 2018. In 2019, octopus landings reached a record level of 55 thousand tonnes before falling sharply to 29 thousand tonnes in 2020. Octopus production reached 27 thousand tonnes in 2021, 25 thousand tonnes in 2022 and 26 thousand tonnes in 2023. The total value of octopus production rose from MRU 411 million in 2006 to MRU 4.02 billion in 2019, before dropping dramatically to MRU 1.01 billion in 2020, MRU 952 million in 2021, MRU 892 million in 2022 and 920 million in 2023. The artisanal pirogues provide the bulk of octopus production, which is exported exclusively to Europe and Asia. Around 22,000 tonnes are frozen, 1,000 tonnes undergo industrial processing, and over 24,000 tonnes are exported, bringing in foreign currency for the Mauritanian economy. We recommend a reduction in fishing effort and improvement in policies to sustain the octopus fishery. Additionally, there should be professional training for artisanal fishermen in fishing techniques to reduce overcapacity in octopus fishing, which will enable fishermen to switch to other fishing techniques and target other fish species.

Unconfined gravity current interactions with orthogonal topography: Implications for combined‐flow processes and the depositional record

ABSTRACTTurbidity current behaviour is affected by interactions with seafloor topography. Changes in flow dynamics will depend on the orientation and gradient of the topography, and the magnitude and rheology of the incoming flow. A better understanding of how unconfined turbidity currents interact with topography will improve interpretations of the stratigraphic record, and is addressed herein using three‐dimensional flume tank experiments with unconfined saline density currents that enter a horizontal basin before interacting with a ramp orientated perpendicular to flow direction. The incoming flow parameters remained constant, whilst the slope angle was independently varied. On a 20° slope, superelevation of the flow and flow stripping of the upper, dilute region of the flow occurred high on the slope surface. This resulted in a strongly divergent flow and the generation of complex multidirectional flows (i.e. combined flows). The superelevation and extent of flow stripping decreased as the slope angle increased. At 30° and 40°, flow reflection and deflection, respectively, are the dominant flow process at the base of slope, with the reflected or deflected flow interacting with the parental flow, and generating combined flows. Thus, complicated patterns of flow direction and behaviour are documented even on encountering simple, planar topographies orientated perpendicular to flow direction. Combined flows in deep‐water settings have been linked to the interaction of turbidity currents with topography and the formation of internal waves with a dominant oscillatory flow component. Here, combined flow occurs in the absence of an oscillatory component. A new process model for the formation and distribution of hummock‐like bedforms in deep‐marine systems is introduced. This bedform model is coupled to a new understanding of the mechanics of onlap styles (draping versus abrupt pinchout) to produce a spatial model of gravity‐current interaction, and deposition, on slopes to support palaeogeographical reconstructions.