Nobody downloaded yet

Riblets and Tripwires and their role in reducing drag over underwater aerofoils - Essay Example

Comments (0) Cite this document
Riblets and Tripwires, and their Role in Reducing Drag Over Underwater Aerofoils by Your name Subject Tutor name University Date Riblets and Tripwires, and their Role in Reducing Drag over Underwater Aerofoils Introduction Riblets and tripwires are widely explored and documented structures that have a huge potential for use in drag reduction technology…
Download full paperFile format: .doc, available for editing
GRAB THE BEST PAPER95.6% of users find it useful
Riblets and Tripwires and their role in reducing drag over underwater aerofoils
Read TextPreview

Extract of sample "Riblets and Tripwires and their role in reducing drag over underwater aerofoils"

Download file to see previous pages Their optimal specifications, mechanism of functioning and potential applications for drag reduction over underwater aerofoils have also been dealt with. Riblets and tripwires In case of underwater vehicles, fluid mechanical drag (hydrodynamic drag) reduces the speed with which they travel through water. For a specific limit of engine power, the maximum speed that can be attained by the vehicle is drastically reduced due to the formation of eddies very close to the surface of the vehicle. Apart from this, another source of hydrodynamic drag is the development of pressure drag due to laminar flow at the boundary layers. Riblets can be used to reduce the formation of eddies near the surface of the vehicle, while tripwires can be used to reduce the pressure drag and induce turbulence at the boundary layers. Riblets: These are minute grooves, longitudinally placed on the surface of a vehicle or airfoil, and are in alignment with the direction of flow. They “have been shown by Walsh and Lindemann [1984] at the National Aeronautics and Space Administration (NASA) and Reidy and Anderson [1988] at the Naval Ocean Systems Center (NOSC) to produce as much as 8 percent turbulent flow drag reduction on flat plates”.1 Studies on “fully submerged axisymmetric bodies”1 conducted by Beauchamp and Philips [1986 and 1987], have shown that the use of riblets reduces skin friction by seven percent.1 Tripwires: Tripwires, also known as turbulators, are thin wires that are attached at the hull of a vehicle or at the nose of a submarine or aircraft. These are used to “trip” or disturb the boundary layer and introduce turbulence, thereby reducing pressure drag. These are “one of the oldest and most used methods of turbulence stimulation”.2 1. Mechanism To comprehend the mechanism of functioning of riblets and tripwires, it is essential to understand the types of drag imposed on a vehicle and the process of their induction. The total drag experienced by a body, includes a combination of pressure and friction. The frictional drag can be reduced by using smooth surfaces. However, studies have shown that this form of drag is further reduced with the help of riblets. The boundary layer of flow around a vehicle can be distinguished into three parts, “a relatively small viscous sublayer, the middle buffer layer and the logarithmic layer”.3 The riblets that are used to reduce drag “extend into the buffer layer. With this kind of riblets a drag reduction of about 8-10%” has been achieved. This is because the riblets restrain the movement of eddies, which are prevented from coming very close, within 50 microns, to the surface of the aircraft or vehicle. “By keeping the eddies this tiny distance away, the riblets prevent the eddies from transporting high-speed fluid close to the surface, where it decelerates and saps the aircraft's momentum”.4 To reduce the pressure drag over a vehicle, tripwires are used. Pressure drag occurs when there is a “lack of pressure recovery on the back of the body, due to separation of the flow around the body”.5 This results from laminar flow in the boundary layer around the vehicle. By using tripwires, it is possible to induce turbulence in this laminar layer, thereby reducing pressure drag. 2. Optimal Specifications The extent of drag reduction is found to increase with the size of riblets. However, for very ...Download file to see next pagesRead More
Cite this document
  • APA
  • MLA
(“Riblets and Tripwires and their role in reducing drag over underwater Essay”, n.d.)
Retrieved from
(Riblets and Tripwires and Their Role in Reducing Drag over Underwater Essay)
“Riblets and Tripwires and Their Role in Reducing Drag over Underwater Essay”, n.d.
  • Cited: 0 times
Comments (0)
Click to create a comment or rate a document

CHECK THESE SAMPLES OF Riblets and Tripwires and their role in reducing drag over underwater aerofoils

Underwater Communication

...?Underwater Communication Underwater communication is one of the most important prerequisite in any form of explorations or venture under water due to the fact that it can ensure safety and can guide divers or vessels in different activities. The paper is aimed to present the different methods and forms of underwater communication. The Different Types of Underwater Communication Diver Underwater Communications One of the most common uses of underwater communication technologies is for the divers. There are types of underwater communication gadgets used by the divers. These include the tools used to communicate to the surface and the tools used to communicate with another diver. To communicate with the surface, the diver uses tools... to...
3 Pages(750 words)Essay

Deep Green Underwater Kite

.... The use of renewable energies is one of the steps taken to reduce the negative impact on environment by reducing the potentials of pollution and its extent. There are other reasons for the rapid advancements in the technological world. The major reason for making these rapid advancements possible and available to the people is the increasing population and its demand. The overwhelming increase in the population leads to demands which are impossible to be met using the old technologies. New ways of production and manufacturing are being utilized to meet the demands of the growing population. Limited energy supply is one of the reasons we need latest technologies. Deep Green Underwater...
5 Pages(1250 words)Essay

Drag Racing as dark play

...? Drag Racing as Dark Play Deep play, dark play and are some theories to describe an event or situation like horse racing or Russian roulette in which the threat to life is at maximum level. The involvement in the sport or event is so high that it makes people think if its really worth engaging in it. Deep and dark play creates a situation in which the life of that person is entirely dependent on that entourage. The characters might not even realize how grave the risk is before committing themselves to that situation. Vanishing Point, a 1971 American movie, explores the concept of deep play very well. The movie shows a delivery driver, Kowalsky, who agrees to take a car to San Francisco from Colorado. Kowasky is shown as...
4 Pages(1000 words)Research Paper

The Scouring of Underwater Pipelines

...Computation of bending moment in pipeline 25 4. Results & Analysis 26 4.1 Scour propagation rates 26 4.2 Impact of scour length on pipe durability 27 5. Discussions 32 6. Conclusions & recommendations 34 5.2 Conclusions 34 5.3 Recommendations 35 7. References. 37 1. Introduction 1.1 Scour and the reasons for its occurrence. Scour is a natural phenomenon that occurs below all the underwater structures like bridge piers, vertical pilings, seawalls, break water structures and pipelines. Scouring of structures could cause extensive damage that reduces the functionality of the project itself. From the various field...
26 Pages(6500 words)Dissertation

Breathing underwater

...Breathing Underwater Order No. 343892 No. of pages: 4 6530 Introduction ‘Breathing Underwater’ is a gripping story of a young sixteen year old youth named Nick Andreas, who looked charming and handsome to the world around him – his friends, family and even to his girlfriend Caitlin Alyssa McCourt, but had quite a different personality on the inside and who knew the reality better, than Nick himself. Things seemed normal and perfect from the outside but the only person that knew otherwise was Nick, who tried his best to fool everyone around with his calm demeanor. Life for Nick in the affluent area of South Florida was a dream. He had it all – a rich family, plenty of money, a good school and classmates...
4 Pages(1000 words)Essay

The benefit of drag race

... engineering, technology and product development are vital for achieving the objective of wining the drag race. This enables competitors to improve their brand perception and come up with innovation. Competitors might be renowned all over the world. But the start of a racing track can position the brand on world stage. The introduction of new facility and new arena for drag racing can create possible entertainment venue for people. Safety of the drivers, better automobile fuels and other innovation can enhance the brand name. Drag racing can attract viewers around the world. A new competitorwho wants to sustain in the competitive market has to innovate and introduce new advance technology. The development of product and technology... The...
8 Pages(2000 words)Research Paper

Drag racing in Terre Haute

... too keyed up to be bothered. I hardly slept Thursday night as I anticipated the next day’s turn of events. Come Friday night and we were all geared up with our own street cars to take part in the race. Our excitement was however dialed down when we had to read the rules concerning the race. Any slight error could lead to disqualification. It was here where I learnt that drag racing was a type of motor vehicle racing where vehicles usually compete in sets of twos to cross a finish line that was set. The race followed a straight course that was short over a distance that was measured. Some of my friends were a bit disappointed with this information since they had hoped it would be a race like that of the world’s greatest drag race... ...
3 Pages(750 words)Assignment

Aerofoils - What Speed Increase do Aerofoils Give to an F1 Car

...of the car with the Aerofoils The primary function of the aerofoils is to create a down force, that aids in pushing the tyres of the car onto the track and consequently improve the cornering forces; and minimise the drag that is brought about by turbulence and finally act to slow the car down (Formula1, 2014). Using the aerofoil software, the lift force, equivalent to the down force in Formula 1 cars, is equal to for an aerofoil of span and chord of. Thus, the total down ward force is equal to the value of the weight of the car, , and the aerofoil down force of . In this case, the centripetal force, , is directly proportional to the...
10 Pages(2500 words)Book Report/Review

Aerofoils - How Wings Work Tasks

...Aerofoil - How Wings Work Tasks Aerofoil - How Wings Work Tasks Introduction In designing operational airplane wings, the most indispensable factors to consider involve size and shape. Size and shape are essential in enabling efficient movement of airplane through space by minimizing resistance to the moving air. It is imperative for airplane designers to comprehend mechanisms leading to generation of drag and lift. Comprehensive understanding of how airplane wings operate in relation to their design is authoritative in realization an efficient aircraft. Question 1 In modern education and society different misconceptions exists in relation to the process of generation of...
9 Pages(2250 words)Book Report/Review

Design Aspects of Riblets for Fluid Drag Reduction: A Review

...shapes on reducing the effects of drag force. Contents ABSTRACT 1 Introduction 2 Analysis of the shark skin 4 Reduction of skin friction 5 Review of Riblet Grooves as a technique of reducing skin friction 7 Conclusion 13 References 14 Introduction Most of fluid dynamic applications rely on the use of energy to either facilitate movement of solid or solid bodies through fluids as well as maintaining fluid motion over the surface of a solid body (Rohr, Anderson and Reidy, 1989).The two cases require energy in overcoming the available drag force (Walsh, 1990). Due to the increased demand of energy to facilitate the success of...
14 Pages(3500 words)Article
sponsored ads
We use cookies to create the best experience for you. Keep on browsing if you are OK with that, or find out how to manage cookies.

Let us find you another Essay on topic Riblets and Tripwires and their role in reducing drag over underwater aerofoils for FREE!

Contact Us