Wind tunnel Definition and 108 Threads

Hi, I teach a high school Aerospace Engineering course. We have a small wind tunnel that can reach about 85 mph, and test objects roughly the size of a 3x5 notecard. It has a pitot tube and force scale. In the past we have constructed airfoils using their 4 or 5 digit NACA codes, then tested...

I'm a student at a community college that was gifted a wind tunnel by a local uni. I'm leading a group of 5+ engineering / science students to refurbish and tune it. The testing chamber is around 12 x 5 x 5 inches, and we have free reign to do anything we'd like. We've had some ideas like...

For my 12th grade school project, I'm planning to research on the effect of vent ratio on the drag coefficient of round parachutes. My idea was to make small model parachutes and drop them from a height, and derive the drag coefficient after certain assumptions. But I also thought it'd be...

Hello all, i posted this on another forum but didn't get much response, I had an 18” centrifugal fan around around and wanted to see if I can push some real air to make a wind tunnel. I'm just a hobbyist, and like to build and modify cars, figured this would be something to look into. Looks...

how do I calculate static and dynamic pressure for the wind tunnel lab report, drag force, and lift force? Please, anyone? thank you.

Greetings Good People, As the title suggests, I'm having some trouble getting to a 2D model. The process is to select an aircraft (or wing model), and model it as a 2D, 2DOF wing-tunnel model. The aircraft I selected was a Cessna 172. This had a tapered wing, which after some calculations and...

An airfoil section in a wind tunnel has many static ports/holes/taps on its upper and lower surface. These static ports can only read static pressure which acts perpendicularly to the local airfoil surface. In place A are static ports that read a pressure value of relative -100 Pa . This...

I assume that air have ##1 kg/m^3## density. Therefore, using Bernoulli equation, on upside and downside of my test object, there is a differential pressure ##\Delta P##: $$\Delta P=0.5*(v_2^2 - v_1^2)$$ From cases: (a) ##v_1 = 1 m/s## and ##v_2 = 2 m/s##, then ##\Delta P = 1,5 Pa## (b) ##v_1 =...

Does wall to wall airfoil produce downwash in wind tunnel ?

Hoping that someone can explain what the optimum angular displacement between the front and rear propellers actually means here in the following paragraph. It concerns the single-rotation case of the experiment: "Both the eight-blade single- and dual-rotating propellers were mounted in four-way...

Hey guys, I'm not sure this is necessarily a physics question, so if it's not I'd appreciate it if someone could point me in the right direction; but here goes. I've been giving some thought to building a wind tunnel lately, I realize this won't be cheap on any large scale, but I just want to...

Hi everyone, I will be conducting wind tunnel tests of a NACA 0012 airfoil to obtain values of lift and drag in a low-speed wind tunnel (approx M = 0.1). I am looking for a really simple way of measuring these forces. Does anyone know of ways to achieve this? I am aware of force balance...

Hello guys, I am trying to calculate the lift force and drag force in a wind tunnel at my school as a part of a project that i am doing. I am varying the length of the airfoils and trying to measure the lift force and drag force. I have 3-d printed 7 airfoils. However, I am not able to find any...

Ive done some wind tunnel experiments for a wing design i made, the wind tunnel was set to 50% power and the incidence angle was increased from -2 to 14 at 2 deg increments, how do i calculate the velocity for each recording? I've done this before but I am just having a mental block on...

Hi everyone, I am new and I hope I'm putting this in the right section. I am currently a Sophomore in High school and I am building a wind tunnel. It's not for a class but rather its is like an independent study. I have been into planes pretty much all my life and I am hoping to get a pilots...

Homework Statement Using a wind tunnel to measure force and velocity at different drive %, we obtained some data for drag. We used one dimpled sphere and one smooth sphere. There are a couple of questions I am stuck on. "The force you have measured is known as the drag force and can be...

Hi everyone, I am currently doing my Computer Science A-Level project and I'm thinking of simulating a wind tunnel but I am also having a really hard time figuring out how to start. I am programming it in Visual Basic (XNA) and using Blender for models. Could anyone guide me in the right...

Hi all, I am trying to design a open circuit wind tunnel, and I've got to the point where a fan should be selected. However, I am not familiar with fans at all, so I am wondering if you could help me! My understanding is that the fan selection process is quite similar to the pump selection...

I want to build a computer simulated wind tunnel. I have experience building physics simulators. I undersand that there are already some existing free wind tunnel simulators out there, but do they work at supersonic speeds? I want to predict the drag coefficient of various rockets and bullets at...

I try to understan this article: https://en.wikipedia.org/wiki/Reynolds_number What does "... such as between an aircraft model in a wind tunnel and the full size version." mean? Why cannot we use a full size version in a wind tunnel or why cannot model be full size? Thank you.

Hi! I would like to submit a model glider to a CFD wind tunnel so I can determine what would be its optimum glide ratio and forward speed at this incidence. I am not supposed to know in advance the range of speed this glider can fly (between stall and structural damage), so the speed I will...

I need 250 m/s of airflow speed in a wind tunnel. I can assume for this purpose, the test section of the wind tunnel has uniform flow. However, the wind tunnel can only generate a flow rate of 100 m/s but the pressure can be increased. I am drawing a blank on how could a generic boundary layer...

I'm nearly at the end of my preliminary testing for a wind tunnel in my A2 physics coursework. My question for my project so far is: "Do different shaped objects exhibit different properties under the influence of high speed air". For my coursework I need to measure or observe something to get a...

I hope this question doesn't have too obvious of an answer. Basically, I still cannot grasp why Bernoulli's equation applies for wind tunnels and pitot-static probes. According to my textbook ("Introduction to Flight" by Anderson), Bernoulli's equation holds only when comparing two points...

Hi All, I'm hoping to work on deriving the governing fluid flow equations for a frisbee in flight theoretically and then to test it on a wind tunnel, and compare results. If u could please help on how do i apply/derive the necessary equations. Respectful Regards

Hi, this is my first post. I teach high school physics and am trying to build a simple wind tunnel. For my first attempt I used a Utilitech high capacity 20 inch fan (nominal 6800 CFM) but the resulting air speed was disappointing – only 4.8 m/s. What type of fan would be better? I was...

I posted this on Eng-tips and no replies yet:( I'm trying to design an as-simple-and-cheap-as-possible supersonic wind tunnel using an air compressor (this even possible? given the energy losses from shock waves...). I have access to a Porter-Cable 150psi, .8hp air compressor. Questions: 1...

I'm looking for a two element 3D wind tunnel app. Any out there that will run on a PC?

Hello.I need help with wind tunnel.The test section is 2m x 2.5 m x 5 m long.How do I work out size of inlet cone.Thanks in advance

Hi All! as you can see I'm new here! i signed up in order to ask for a wee bit of help with my thesis! (now don't get me wrong I am not exactly asking anyone to write it for me!) I've found myself at a small bit of a loose end here, as a mechanical engineering student i am perfectly capable of...

Is there an equation to calculate the oblique shock angle for supersonic flow when the given angle of attack is greater than 0, but less than the half angle? In my particular practical experiment, the half angle of the aerofoil is 5 degrees, so want to get a variety of figures between 5 and -5...

I am a skydiving coach and I am trying to figure out how many pounds of force wind moving approximately 120 mph has on something with a surface area of 25 square inches. I know turbulence and compression play into it as we'll but I just want a general formula to figure it out. The object is...

Homework Statement A wind tunnel is designed to draw in air from the atmosphere and produce a velocity of 100m/s in the test section. THe fan is located downstream of the test section. What pressure is to be expected in the test section if the atmospheric temperature and pressure are -20C...

Hey everyone, I'm a student working on building a wind tunnel with some classmates. I'm in charge of figuring out the drag and lift force sensors. I'm currently looking these two components: http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_2128260_-1...

For my senior design project, I have to reduce the aerodynamic drag of a truck and trailer. I am doing CFD simulations and wind tunnel testing. The dimensions of the wind tunnel (test section) are 94 in long, 13.5 in tall and 20 in wide and a cross-sectional area of 270 in^2 and it could go up...

Hi guys! I am doing a project for my High School, here in Spain, that is obligatory for everyone. As a love everything related with planes and aerodynamics I've decided to create this wind tunnel. Is approximately 2,15 meters long and it weights around 10 kilos. It is made 100% of wood and it...

Hello everyone, the forum looks great and I have been reading it for a long time, but I have only registered. I am writing this post because I have to analyse two flow fields in a wind tunnel. 1) The first flow is generated from a helicopter blade, with Re=2000000, Mach=0.92 and...

Can a wind tunnel get up to scramjet speeds; ie. Mach 6-12?

Hey guys, so I'm building a mini wind tunnel and I would like to calculate the new RPM,HP and Torque since the propeller will act as a load and change the specs of the motor(note I'm using a air wrench as the motor as it's all I had around and have disabled the impact motion) the current specs...

Hi, I am currently researching methods available for manufacturing a half-span wing model (approx 0.5m span, low sweep delta wing of varying cross section) to be used in wind tunnel experiments. A recent paper suggested the use of epoxy and micro glass beads injected into an aluminium mold...

Is there any significance in repeating a water tunnel study in a wind tunnel? If so, would the results be publishable or would it just be considered repetition of a previously published water tunnel study?

Hi, I have built an 8' long wind tunnel for use in an experiment to test the effects of turbulence on several variables. However, seeing as this is an educational-level/novice wind tunnel with a fan rating of ~1800 cfm the wind speeds only really go up to ~10 mph. From my understanding, this...

Hey everybody, I have built a 7' wind tunnel. The test section is 7''x7'' and 24" long. The diffuser opens to 22''. I would like to achieve around 30mph through the test section. I am having trouble finding a fan that can meet that need. I have looked into using an electronic radiator...

How would a strain gage be set up (on top of the model? around the sting?) to measure drag? I don't quite understand the connection between the force of drag and some sort of compression/tension force...? Thanks for the clarification.

Homework Statement Recently I've been given an assignment Build a Wind Tunnel(That can generated wind speed of 20m/s) -Izzit the chamber(whole tunnel) must be sealed ? -The material of the wind tunnel must be transparent(something like plastic?)on the test section?? Homework...

Hello, My name is Ryan and I'm a volunteer instructor with the local Royal Canadian Air Cadet squadron. I'm looking for ways to try and make the kids' aviation lessons more interactive and hands on, and so I've decided I'd like to build them a small wind tunnel, purely for flow visualization...

I am designing a wind tunnel for my final year project. I am am now a little lost at the power requirements area. To select a fan, i understand that i have to overcome the pressure drops through out the tunnel by choosing a fan that has a higher pressure rise. So far i have figured out that i...

when calculating a Reynolds number for an obstacle in wind tunnel Re = air density * air velocity * D / Dynamic viscosity D here is the characteristic length of the immersed body ( frontal length ) 2 dimensional problem Or the Hydraulic diameter which relates the tunnel dimensions to the...

I will do research on the vertical single strut. i want to ask if there is something interesting to study?

Hello, I’m designing a 2D wind tunnel model for my master thesis. It will be a profile equipped with a fixed hinged trailing edge flap. I’m going to measure at different angle of attacks and different flap settings at low speeds (about 70 to 100 m/s). The aim is to measure steady and unsteady...