Aerodynamics Definition and 245 Threads

Homework Statement hello, i have been given a piece of homework which is determining the characteristics on an aerofoils boundary layer. In the brief the following statement is made with no context “Aerofoil is flying in chord Reynolds number 0.2x10^6” am i correct in saying that is the point...

<< Mentor Note -- thread moved from the technical forums so no Template is shown >> Hello, I built a hovercraft not long ago for an experiment. What I did was applying more power to the motor and looking at how high the hovercraft could go. However, the formula that I was planning to use, uses...

Hi! I'm trying to analyse how aerodynamics affect a rockets movement, I am having a bit of trouble though. Any tips on how i would start out or look? The method is supposed to include differential equations which i am familiar with but have a bit of trouble tieing it all together. Where do i...

Problem How to calculate the drag force of the model helicopter using the given data above? Research Question How does increasing the length of the wing planform of a model paper helicopter affect the time it takes the helicopter to fall to the ground and hence the air resistance? Variables...

What is the coefficient of drag on a flat surface? Note: The body is in free fall The object has 2 wings planform (it's a paper helicopter), which is flat The object's wing spin in a circular motion (anti-clockwise) during free fall

Homework Statement How to find the velocity of the air flow around the aerofoil? Homework Equations U - freesteam velocity β - angle of wing camber The Attempt at a Solution To find the velocity of the air flow at each section of the aerofoil, am I right to say that the horizontal velocity...

Hello! I am a High School senior planning on doing a project for my Diploma which is based on Aerodynamics. Now, I have looked into the basic physics that goes behind airfoils and their forces. However, I am looking for an experiment idea that is somewhat higher level (maybe undergrad level). I...

Homework Statement - Question: Which cyclist (A, B or C) profits the most from cyclist slipstream (also called “aerodynamic drafting”)? - Given: the direction of the wind, the positions of each cyclist; an illustration representing this - NOTE that I am expected to solve this question...

According to wikipedia "The onset of turbulence can be predicted by the Reynolds number, which is the ratio of inertial forces to viscous forces within a fluid which is subject to relative internal movement due to different fluid velocities, in what is known as a boundary layer in the case of a...

Hello all... I have a question about an engine-driven propeller. While a propeller is being spun, the air resists it and the maximum power of the engine will turn at "max rpm" when the drag from the air interacting with the propeller becomes equal to the torque generated by that engine. Now...

When I type "drag coefficient" in Google, and view some of the images, the standard list of geometrical shapes come into view, such as this one: https://upload.wikimedia.org/wikipedia/commons/thumb/3/37/14ilf1l.svg/220px-14ilf1l.svg.png If we take the cone for example, there is a drag...

Hello, I am currently doing research on the aerodynamic properties of a rotating cylinder in a cylindrical housing. The cylinder represents a rotor in a electric motor. The air gap between rotor and stator is about 0.5mm. I'm looking for a theoretical analysis and calculation on the...

Hello. I read an article about aerodynamics. http://www.cyclist.co.uk/in-depth/2873/fat-v-skinny-who-goes-downhill-faster I'm a little bit confused with this statement regarding mass, drag, and velocity: "When you increase the mass the speed increases by cubic function, whereas if you...

How does speed effect the recirculation zone and wake for supersonic and hypersonic speeds? Does it get longer, wider? Also this is for a blunt body like apollo reentering

This is a question about reentry aerodynamics How are aerodynamic characteristics found? I know that aerodynamic equations are not that accurate, and the best way to do it is by simulation. I also heard that if you want it to be precise, you add corrective factors to the calculations. How do...

I'm going to be an aerospace/mechanical engineering student at UAH next year and I am coming up with my four year plan. Two courses, "fundamentals of aerodynamics" and "compressible aerodynamics", are not prerequisites for each other, and they are both required. Based on your experience with...

I created a model on autodesk inventor of a concept model kite that would stay in high altitudes and take in wind energy through the cone opening. Is there any advice you can give me about the aerodynamics of this model? (There are balloons that provide lift above the wings, and I want the...

I am curious about a reverse wing sweep because it could be used on an aircraft for turning at high speeds at higher than Mach two.

Could multiple, smaller rotors on a wind turbine (on the same shaft) be more effective than a single, larger rotor? Why do most wind turbines have only one big rotor? I was thinking about doing a science fair project on this topic, but I have been unable to find a conclusive answer to this...

Homework Statement The single wheel of an aircraft can undergo a max of 7500N at a vertical velocity of 8 m/s on landing. The vertical spring moves in SHM and has a stiffness of 600N/mm. The systems vertical damper has a damping coefficient of 38 x 10^3 Ns.m-1 Homework Equations F=Kx...

I have a huge interest in aviation and aerodynamics, despite being an EE student. I took Fluid Mechanics courses as electives, and I'm learning some aerodynamics on my own. I was thinking if there is any field of work where the knowledge of both an EE and aerodynamics/flight mechanics would be...

Let's imagine that we fire a cannon located on a platform high above the ground and we want to compute the time after which the horizontal velocity of the cannonball will be zero. Let's assume that we shoot at 0 degree angle. 1. Air resistance force F = C_d \frac{\rho v^2}{2}S 2. Assuming that...

I have been involved in a fairly furious debate about a fluid dynamics experiment regarding the pressure of air passing through a tube attached to a moving car. It is similar in concept to the issue of whether or not an opening in an aeroplane fuselage would suck people out, where the opening...

Homework Statement This problem is from "Fundamentals of aerodynamics" by John D. Anderson, Jr (Fifth edition, page 101): Consider a flat plate at zero angle of attack in a hypersonic flow at Mach 10 at standard sea level conditions. At a point 0.5 m downstream from the leading edge, the local...

I am currently engineering my v2 version of my f1 in schools car, it is a small scale car powered by a CO2 cartridge designed to go down a 25m track, my current version does 25m in under 1.4s, however, I would like to shave off another 0.3-0.2s I believe my main issues are the bearings (only...

Hi there people, I am Leroy Leon, a film maker and playwright in Nigeria, and I am writing some science fiction films and I need answers with questions on Aerodynamics, slipstream and drag. So, my question is, if I want to create a land vehicle that can travel at hypersonic speeds, the...

I'm working with data across an airfoil and need some help. We've got Kulite sensor data along 3 chord lengths of a certain NACA airfoil. The case is of an incompressible flow. I need to determine the coefficient of pressure at these sensor locations using total pressure measured and I...

I'm now taking classes on mechanical vibrations and fluid dynamics, and those are two fields that are very interesting to me. I've always liked the subject of aerodynamics, but now I'm really liking to study mechanical vibrations, very interesting field of study. I'm looking for some specialty...

I'm looking to just do some great reading on my own and want some suggestions. I could only use one prefix.

So I've decided to subject my little Suzuki Samurai to some home-spun garage surgery. Converting to a full sequential MPFI. (and doing a little porting along the way). Now for the physics(ish) bit. See image of intake cutaway. The blue arrow points to the sharp ('cut -off') trailing edge of the...

I'd like to experimentally simulate air flow turbulences around obstacles. Building the obstacles in one thing, but providing a well characterised flow (and mix it with something visible like smoke...) is something else. In general, I think the whole idea is easier to acomplish compared to fluid...

Hi Great Engineers, Need you help. I am required to calculate drag load on sticker to ensure it is not peeling off in operation. The vehicle may moves as fast as 220 km/hr with rectangular sticker size of 30 cm x 40 cm, thickness 0.0635 mm on its body. Wind direction is parallel to 40 cm length...

Homework Statement In the three-dimensional flow from a point source, the streamlines radiate in all directions from a point. If we designate the strength of the course as Λ' show that |V|= Λ'/4*Pi*r^2 So I've been trying to read the text and understand what this asking/how to solve but I...

Homework Statement The absolute value of the velocity and the equation of the streamlines in a velocity field are given, respectively, |V|=sqrt(x^2+2xy+2y^2) and y^2+2xy = C Find expressions for u and v. Homework Equations dy/dx = v/u |v| = sqrt(u^2+v^2) The Attempt at a Solution included...

A flying object is moving in 3D space having translational velocity and the object is also rotating. Consider a body frame (xb-yb-zb) attached to the C.G of the moving body. Hence the body attached frame is also translating and rotating (as the object is flying) with respect to a fixed inertial...

Homework Statement So, I have this problem here that's pretty basic, but the solution manual sets different axes, and I'm having a bit of trouble understanding the geometry part, meaning how he applies the given forces to the new axes. A model airplane of mass 0.750 kg fl ies with a speed...

Hi, my name is Andy. I'm a B.Sc. (physics) from McGill in 1982. Ph.D. (mech. and aerospace eng.) from Rutgers in 1994. I'm a cycling aerodynamicist for pro and Olympic teams.

I know that the surface roughness plays an role in the Magnus force exerted of a rotating cylinder. But, i cannot find an equation that includes the surface roughness in the equation of the Magnus force. If someone could state the formula (and preferably a source to read up more on it) it would...

To approximate windspeeds we normally use the natural logarithm relation: u_air = V ln [ (z-d) / z_0 ]Where: V - Characteristic speed, constant z - height from the ground z_0 - roughness length, constant d - zero plane displacement, constant The Betz limit tells us that in theory that the max...

What is the difference between an automotive spoiler and an automotive wing? Is there a difference? My understanding has always been that a wing is an airfoil, and is used to produce downforce, while a spoiler is is just a lip that is used to reduce drag by creating a pocket of stagnant air...

I'm wondering about theoretical maximum velocities of supersonic electric aircraft. I think the fastest demonstration of any type of aircraft has been close to mach 10. This was done using a rocket engine, so propulsion would not be limited by air characteristics as much as a fan's propulsion...

I am a computer science undergrad (almost done, so I can't switch to engineering sadly) and I was wondering if someone from the physics/engineering community could advise me on this. I know it sounds crazy but my question is: Is it possible/reasonable to teach oneself the physics, aeronautical...

How would one calculate the drag on a projectile (in this case a 1cm3 cube) that was launched at 0°. The vertical drop, initial velocity, distance, and time (taken to travel distance) where measured. I want to say that I could compare these experimental drop (bellow hight that projectile was...

I've noticed that many later-model sport sedans and some other vehicles have a new shape for their wheel well fenders. The fenders flare from the car body, and end with a several centimeter flat section before the wheel well. It seems to be a feature across several car brands and models, and...

Doing my undergrad thesis on a ramjet and am confused about scramjets. A ramjet's diffuser slows down supersonic inlet flow to low subsonic to allow combustion. But a scramjet's diffuser first slows the flow down, then speeds it back up in the "diverging" section for supersonic combustion. Why...

In class, of all the shapes we tested, the pinwheel won in the total amount of current and voltage, power generated. (used a regular fan and blew a bunch of different blade designs) Question is, why don't we see pinwheels designs for turbines? Where else can I look for turbines designs? Thanks.

I set up two canister vacuum cleaners facing each other: I had the idea that if there was some circulation in the air (provided by the small fan) then a vortex would form between the inlets. This does not seem to work. I don't have much knowledge or intuition about aerodynamics. Would this...

I've read somewhere that supersonic waves behave like supercritical flow of fluids and that subsonic waves behave similarly to that of subcritical flow. I guess an example of subcritical flow is pinching a hose and supercritical is how water flows over rocks (a bit more confused on that). Can...

As I have looked through the internet and did my research I have found some information on how to calculate the drag coefficient, however none of what I have search for matches what I need. Currently I am doing a physics assignment for grade 12 and I am investigating the physics behind...

The question is which is better from the efficiency point of view: One big propeller or multiple smaller ones? Or are they the same? My general impression is that a bigger one will have much more better efficiency as if you consider the following points: 1. lift is proportional to the area of...