What is Aerodynamics: Definition and 241 Discussions
Aerodynamics, from Greek ἀήρ aero (air) + δυναμική (dynamics), is the study of motion of air, particularly when affected by a solid object, such as an airplane wing. It is a sub-field of fluid dynamics and gas dynamics, and many aspects of aerodynamics theory are common to these fields. The term aerodynamics is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air.
The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simulations has formed a rational basis for the development of heavier-than-air flight and a number of other technologies. Recent work in aerodynamics has focused on issues related to compressible flow, turbulence, and boundary layers and has become increasingly computational in nature.
The Navier-Stokes equation is solved in a vector grid in a Cartesian coordinate system. That is, rectangular. But does a rectangular mesh relate to what happens in a gas or liquid, and is it better to use a triangular mesh?
Undoubtedly, it is incredibly difficult to take into account all the...
For the avaliable power to be harvested in free-streaming wind:
P=1/2QU^2_infinite (Q: mass flow rate, U_infinite: velocity of free-streaming wind)
And
Q is defined as: p x U_infinite x A_d. (p: density of air, A_d: Area of disc)
I cannot understand the reason of taking the area of disc, A_d...
Hi everyone. I was wondering if you guys could explain me why I saw people say that:
Induced drag changes for a factor of 1/V2
Induced drag coefficient for a factor of 1/V4
If I don't make any mistakes, Drag = 1/2 rho * S * V² * Cd.
Manipulating the formula I find, 1/Cd = 1/2 rho * S * V² *...
I have a model for airs density as a function of height
I would imagine the speed can be describes as the angular velocity times length
The coefficient of drag can be found online, seems to be around 1.17 for a cylinder
It seems to me that im going to need an integral somewhere, but can't quite...
I am currently taking some time off of college (I am a sophomore), and I'm trying to continue coding and experimenting with Calculus-y math as I'll be going into Calculus II and then III when I go back. I am currently trying to develop a 3D baseball pitch visualizer for my own purposes. I am not...
I am putting this in General Discussion because it could go into either biology or aerodynamics.
Remember how bumble bees were not supposed to be able to fly aerodynamically?
This explains why that is wrong.
Here is a podcast I just found (came out in 2019).
The two podcast guys interview...
TL;DR Summary: Using the surrounding airflow to deduce the physics around UAP/UFO
Now that NASA is in the mix for investigating UAP/UFOs - I started wondering at what their approach might be. I'm thinking they might be able to work from the outside in, toward the object/sensor(y) artifact...
TL;DR Summary: I want to know some good resourced on aerodynamics and the viability of a project I want to make.
Hey everyone! First post here, so if I do something wrong please do tell me :)
What are some good resources for getting into aerospace engineering and aerodynamics? I currently have...
This is question for aerodynamicist, so I put it here in aerospace department.
(Mechanical engineers don't learn aerodynamics at university)
What is aerodynamic function of active front lip spoiler (on video) and what is function of flexibile plate infront of front tyers(picture)?
Why reduce...
Hello,
Can someone recommend me a good textbook to (self-)study aerodynamics, optimally with focus on aircrafts. I am a graduated student in physics and therefore familiar with all the basic concepts of fluiddynamics and calculus. But, apart from that, I have no further knowledge in the field...
Summary:: I'm looking for recommendations of recent aerodynamics monographs which treat high Mach number subsonic (pre-transsonic) flight thoroughly.
I'm looking for recommendations of recent aerodynamics monographs which treat high Mach number subsonic (pre-transsonic) flight thoroughly. I...
Hi all,
I have some data from an automatic weather station, with recordings of both 2m air temperature and 2m air pressure and also the surface temperature. Is it possible to estimate vertical wind speeds between the AWS and the surface based upon this data? Imagine T_a = 15 degrees and T_s =...
First off: I'm currently working on an RC car heavily focused on aerodynamics for a Project I'd like to add to my Uni application. I've created a model, ran it through CFD and came up with some numbers. Now I'd love to plot out an equation that displays either speed or acceleration in dependence...
We know that the definition of the pressure coefficient is $$C_p=\frac{p-p_\infty}{q_\infty}$$, where ##p## is the pressure at a point, ##p_\infty## is the ambient pressure (free-stream), and ##q_\infty## is the free-stream dynamic pressure.
We also know that the Bernoulli's equation is...
Hello,
I would like to ask one question. What is the equation for the lift force of a rotating sphere when flying through the air:
m = 0.25 g
v = 130 m/s
angular velocity = 105 rad/s
radius = 3 mm
air density = 1.2292 kg/m^3
air pressure = 101200 Pa
air temperature = 15 °C = 288.15 K
If anyone...
Aerosol particles with an average diameter of 5 μm and a density of 1000 kg / m3 are spread to a room with a floor area of 20 m2 and a height of 3.5 m. How long does it take for all 5 μm particles to settle on the floor (dry deposition)? The answer should be 1 hour and 20 minutes.
Hey all,
I recently took an aerodynamics exam that included the question "Please Explain how the Bernoulli Equation can be Applied Inside a Boundary Layer". Now, it is my belief that the Bernoulli equation, defined by my textbook as P+0.5ρV2=ℂ, requires inviscid flow to be properly applied...
Hey everyone,
I'm coming to the end of my Mechanical Engineering B.S. degree and I've been in the process of applying to mechanical and aerospace PhD programs. I want to do research in fluid mechanics; I have some expereience in hypersonics from a Research Expereince for Undergraduates NSF...
I thought it would make sense to use the formula f=m*a, but I do t know the acceleration and I don't know what is the average acceleration of a hockey club (guess it depends on strength of the player?).
What is best theoretical shape of undertray for maximum downforce , maybe wing shape or venturi shape?
classic "venturi shape" with diffuser
"wing shape"
Earlier today I realized that, when a strong gust of wind would blow through my area, it would pick up leaves off the ground and typically blow them in circular patterns, and typically the leaves would go in at least several complete circles before coming to rest back down on the ground. Why is...
I am trying to understand how birds fly. If you consider a plane, using it's engine & streamline shape of the wings, it can create a low pressure region above the wings and high pressure region below and this makes it fly and the upward force is proportional to the speed.
Birds seem to flap its...
Hello, all. I work in a warehouse, and in an elevated work area. It's warmer up there because heat rises, but we have a few fans meant to help cool us. Unfortunately, one out of three fans is facing toward another, and I've been trying to explain to my coworkers that if one fan faces another...
Summary:: How can I measure the friction of a train with its rails and the air.
How can I measure the friction of a train with its rails and the air. You can assume that the face of the train is like the picture below.
If you need any specifications just let me know
Short of picking up an aerospace engineering book and learning a lot of complex math, I figured I'd ask here.
Looking at the wing tips of planes like the Spitfire, P-63 Air Cobra, P-47 Thunderbolt, A6M Zero, etc... you'll notice the wing tips are rounded.
Looking at the wing tips of the P-51...
My son and i were discussing aerodynamics and he brought up a paper from https://phys.org/news/2012-01-wings.html It seems that the latest discussions seem to completely discount the differential velocity of air flow as a cause of differential pressure, but point to a differential pressure...
I don't understand aerodynamics and want to learn it.
For example, there are three different cars, car 1, car 2, and car 3 (please see attached image).
The power of all cars are similar, 1000 HP.
The nose (front) of the car 1 is 90 deg, car 2 is 60 deg, and car 3 is 30 deg.
They all have to run...
Why does a helicopter blades operates in an advancing direction while the other, the retreating blades travels backwards? That is, what would happen to the helicopter if the retreating blades were to travel forward like their advancing blades counterparts?
Summary: Basicly i am trying to find out if there's anyway to calculate the diffrence in pressure underneath and above the car so i can calculate the downforce
Hello I am doing a project about aerodynamics of a formula 1 car
when i wanted to do calculations of how much downforce each...
Summary: What could affect Magnus force's magnitude and direction except for speed and spin?
Most golf flight simulators model the coefficient for drag (Cd) and lift (Cl) as a function of the relative spin ratio (rsr), where rsr = spin * radius / speed. In Figure 1, parameters of two similar...
Hi!
I have had this question for ages, nearly impossible to find anything on the web. My experiments confused me even further! Its concerning the blockage effects of surfaces ahead of a propeller. For example let's consider the usual dual vectoring propellers on the sides of airshipcars like...
Hi,
I have a question regarding the tragic crash of the latest 737 Max.
Is it not a huge error in the flight laws and the MCAS software to execute a nose down maneuver at any altitude? Should the system not have a rule to prohibit such a maneuver below a minimum altitude threshold?
I'm also...
Hi,
is there an appropriate method to get the maximum lift coefficient (cl_max) of a wing from the polars of the section airfoils?
The background is that I cut a arbitrary wing into a certain number of sections. After that I use Xfoil to compute the local cl_max. Since this approach neglects...
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
For a flow that is incompressible and low-speed, the aerofoil has a peak pressure coefficient of -0.41. Using the Prandtl-Glauert rule, determine the aerofoil critical Mach number.
Homework Equations
$$c_p = \frac{c_{p,0}}{\sqrt{1-M_{\inf} ^2)}}$$
Ans for Mcr=0.74
The...
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...
I have collected velocity data for a 3-D grid of test section of a low speed wind tunnel.I have tested airfoils for pressure distribution in the same test section for similar free stream conditions. How do I calculate the impact of flow quality in the test section on the test results of pressure...
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...