Direct force measurements and qualitative flow visualization were used to compare flow field evolution versus lift and drag for a nominally two-dimensional rigid flat plate executing smoothed linear pitch ramp manoeuvres in a water tunnel. Non-dimensional pitch rate was varied from 0.01 to 0.5, incidence angle from 0 to 90°, and pitch pivot point from the leading to the trailing edge. For low pitch rates, the main unsteady effect is delay of stall beyond the steady incidence angle. Shifting the time base to account for different pivot points leads to collapse of both lift/drag history and flow field history. For higher rates, a leading edge vortex forms; its history also depends on pitch pivot point, but linear shift in time base is not successful in collapsing lift/drag history. Instead, a phenomenological algebraic relation, valid at the higher pitch rates, accounts for lift and drag for different rates and pivot points, through at least 45° incidence angle.

/pdf/unsteady-pitching-flat-plates-3wg4huf8aq.pdf

Unsteady pitching flat plates

Effect of number of stages on the performance characteristics of modified Savonius hydrokinetic turbine

As an abundant, clean, and predictable source of renewable energy, tidal current energy provides a cost-effective alternative to fossil fuels. Tidal current energy harvesting technologies are still at their early stages of development. Even some advanced demonstration projects with full-scale tidal current energy converters (TCECs) still face considerable technical barriers, and their environmental impacts are unclear. This study presents a comprehensive overview of the state-of-the-art of tidal current energy harvesting schemes and life cycle assessment (LCA) studies of TCECs. By reviewing the state-of-the-art of research and development efforts of tidal current energy harvesting technologies, key advancements required for their successful commercialization at the utility scale in the tidal current energy industry are identified. Detailed LCA studies of TCECs are presented to indicate their energy consumption and environmental impacts. Additionally, some comprehensive comments of development of TCECs and LCA are presented, which can be used to guide decision making towards more sustainable energy practices. 

Tidal current energy harvesting technologies: A review of current status and life cycle assessment

I. Ein Beitrag zur Erklarung des Segelfluges.

Compared with traditional underwater vehicles, bio-inspired fish robots have the advantages of high efficiency, high maneuverability, low noise, and minor fluid disturbance. Therefore, they have gained an increasing research interest, which has led to a great deal of remarkable progress theoretically and practically in recent years. In this review, we first highlight our enhanced scientific understanding of bio-inspired propulsion and sensing underwater and then present the research progress and performance characteristics of different bio-inspired robot fish, classified by the propulsion method. Like the natural fish species they imitate, different types of bionic fish have different morphological structures and distinctive hydrodynamic properties. In addition, we select two pioneering directions about soft robotic control and multi-phase robotics. The hybrid dynamic control of soft robotic systems combines the accuracy of model-based control and the efficiency of model-free control, and is considered the proper way to optimize the classical control model with the intersection of multiple machine learning algorithms. Multi-phase robots provide a broader scope of application compared to ordinary bionic robot fish, with the ability of operating in air or on land outside the fluid. By introducing recent progress in related fields, we summarize the advantages and challenges of soft robotic control and multi-phase robotics, guiding the further development of bionic aquatic robots.

/pdf/recent-progress-in-modeling-and-control-of-bio-inspired-fish-13sv3035.pdf

Recent Progress in Modeling and Control of Bio-Inspired Fish Robots

A review on fluid dynamics of flapping foils

The invention discloses a connecting device of a wave glider water surface floating body and an umbilical cable, and relates to the field of naval architecture and ocean engineering. The device includes a device shell, a first backing plate, a second backing plate, first clamping strips, a latch, second clamping strips and a knob; the device shell is connected to the first backing plate and the second backing plate; the first backing plate is located at the upper part of the second backing plate; the first clamping strips, the latch, the second clamping strips and the knob are arranged at theinternal of the device shell; the first clamping strips fix an umbilical cable joint; the latch and the first clamping strips are in butt joint; the second clamping strips fix the latch; and the knobcontrols the opening and closing of the second clamping strips. An applied method of the device includes inserting the umbilical cable joint into the first clamping strips; inserting the latch into the device shell from top to lock the first clamping strips; and rotating the knob to push the second clamping strips into the groove of the latch so that the latch can be fixed. The device is safe andreliable in structure and convenient in dismounting, and therefore, the navigation safety of a wave glider under severe sea conditions can be guaranteed.

Connecting device of wave glider water surface floating body and umbilical cable

The invention discloses an elastic connection device for a wave glider rope and an underwater gliding body, and relates to the field of ship and ocean engineering. The device comprises a fixed hingedblock, a steering hinged block and an elastic hinged block, wherein the elastic hinged block is divided into an upper part structure and a lower part structure; the lower part structure of the elastichinged block comprises an elastic hinged block housing, a cylindrical steel block, a spring, a rope locking block and an anti-drop steel block. The elastic connection device has the advantages that certain relative displacement in the rope direction is allowed under the situation that connection strength is guaranteed, so that under severe sea conditions, the elastic connection device can delay transmission of vigorous activity of a mother ship on water to the underwater sliding body, impact load is reduced, energy utilization rate is increased, noise is lowered, and the service life is prolonged.

Elastic connection device for wave glider rope and underwater gliding body

The invention discloses an oscillating hydrofoil tidal current energy electricity-generation device, and relates to the field of marine energy development and utilization. The oscillating hydrofoil tidal current energy electricity-generation device comprises a floating-type energy-absorbing electricity generation assembly and a cable assembly, wherein the floating-type energy-absorbing electricitygeneration assembly comprises an energy-absorbing device for converting tidal current energy into mechanical energy, and an electricity generator for converting the mechanical energy into electricalenergy, the energy-absorbing device comprises an oscillating hydrofoil and a rocker arm, at least part of the oscillating hydrofoil is immersed in water, one end of the rocker arm is connected with the oscillating hydrofoil, and the other end of the rocker arm is connected with the electricity generator; and the cable assembly is arranged to anchor the energy-absorbing device and the electricity generator to the seabed. According to the oscillating hydrofoil tidal current energy electricity-generation device, the fixed load of the structure can be effectively lowered, and system stability is improved; and the structure is simple, reliability is high, maintenance is convenient, the maintenance cost is lowered, and environmentally friendliness is achieved.

Oscillating hydrofoil tidal current energy electricity-generation device

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Wu Xia

Author Tools

Chat about Author

Papers

A review on fluid dynamics of flapping foils

Connecting device of wave glider water surface floating body and umbilical cable

Elastic connection device for wave glider rope and underwater gliding body

Oscillating hydrofoil tidal current energy electricity-generation device