Name: wind tunnel testing of a dc-6b model
Uploaded: 2023-04-30T07:03:45.000Z
Duration: 14 min 2 s
Channel: JoVE

K12 Standards

Arizona Science Standards

High School

Physical Science

HS.P3

HS.P3U2.7

aerodynamic-performance-of-a-model-aircraft-the-dc-6b

Aerodynamic Performance of a Model Aircraft: The DC-6B

Настройка модели DC-6B по аэродинамическому балансу сил показана ниже. 
<img src="/files/ftp_upload/10456/10456fig1.jpg"> 
Рисунок 1. Монтируется модель DC-6B. А) Модель DC-6B внутри низкоскоростной испытательной секции аэродинамической трубы с внешним аэродинамическим балансом. Б) Модель DC-6B установлена на весах с помощью трех шарнирных точек. Также имеется мотор регулировки угла рысканья, мотор управления тангажем и электронный уровень для калибровки угла тангажа. 
<img src="/files/ftp_upload/10456/10456fig2.jpg"> 
Рисунок 2. Панель управления аэродинамической трубой на низких скоростях. Угол тангажа и угол рыскания могут управляться электроникой с панели во время испытаний в аэродинамической трубе. 
1. Калибровка настроек
<ol>
	<li>Заблокируйте внешний баланс на панели управления аэродинамической трубой. </li>
	<li>Установите стойки на аэродинамический баланс, как показано на рисунке 1. Стойки крепятся болтами к балансу. </li>
	<li>Установите угол рыскания равным нулю, отрегулировав ручку на двигателе рысканья, и установите угол тангажа равным нулю с помощью мотора тангажа. Угол тангажа должен быть откалиброван с помощью электронного уровня. Измерения сначала делаются под разными углами, на месте только стойки, а не модель самолета. Это позволяет вычесть влияние стоек от самолета. </li>
	<li>Включите компьютер и внешнюю систему сбора силы баланса. Необходимо включить систему не менее чем за 30 минут до тестирования. </li>
	<li>Откройте программное обеспечение для управления измерениями. </li>
	<li>Запишите давление и температуру в помещении. Обязательно скорректируйте барометрическое давление с использованием местной температуры и местной силы тяжести. </li>
	<li>Убедитесь, что на испытательной секции и аэродинамической трубе нет мусора, и ослабьте детали, затем закройте дверцы испытательной секции. </li>
	<li>Разблокируйте внешний баланс и установите скорость в аэродинамической трубе на ноль. </li>
	<li>Включите аэродинамическую трубу и систему охлаждения аэродинамической трубы. </li>
	<li>Записывайте силы баланса и моменты. </li>
	<li>Установите динамическое давление на 7 дюймов H2O и запишите силы баланса и моменты. </li>
	<li>Используйте регулятор рысканья, чтобы установить угол рыскания на 5°. При необходимости отрегулируйте динамическое давление на 7 дюймов H2O. </li>
	<li>Записывайте силы баланса и моменты. Измените угол рыскания на 10°. При необходимости отрегулируйте динамическое давление на 7 дюймов H2O. </li>
	<li>Записывайте силы баланса и моменты. </li>
	<li>Выключите аэродинамическую трубу и заблокируйте внешний баланс. </li>
	<li>Установите модель DC-6B с хвостовой частью. </li>
	<li>Калибруйте угол атаки и индикатор тангажа. Откалибруйте угол наклона перед испытанием с помощью электронного уровня. </li>
	<li>Разблокируйте внешний баланс. </li>
	<li>Установите угол атаки, нажав носом вверх или вниз на пульте управления Рисунок 2. Углы атаки для испытаний α = -6°, -4°, -2°, 0°, 2°, 4°, 6°, 8°, 10°. </li>
	<li>Записывайте силы баланса и моменты. </li>
	<li>Повторяйте шаги с 1.19 по 1.20, постепенно увеличивая угол атаки, пока все контрольные точки не будут пройдены. </li>
	<li>Верните угол атаки, α, в ноль и установите угол рысканья. Углы рыскания для испытаний β = 0°, 5°, 10°. </li>
	<li>Записывайте силы баланса и моменты. </li>
	<li>Повторяйте шаги с 1.22 по 1.23, постепенно увеличивая угол рысканья, пока не будут выполнены все контрольные точки. </li>
	<li>Заблокируйте внешний баланс и снимите хвост с модели DC-6B. Установите хвостовой конус и повторите шаги с 1.19 по 1.24. </li>
	<li>Когда все данные будут собраны, выключите систему охлаждения аэродинамической трубы, заблокируйте внешний баланс и выключите аэродинамическую трубу. </li>
</ol>
2. Испытания при ненулевых скоростях ветра
<ol>
	<li>Проверьте, свободны ли испытательная секция и аэродинамическая труба от мусора и ослабленных деталей, а затем закройте дверцы испытательной секции. </li>
	<li>Установите угол тангажа равным нулю. </li>
	<li>Разблокируйте внешний баланс. </li>
	<li>Установите диск скоростей в аэродинамической трубе на ноль и включите аэродинамическую трубу и систему охлаждения ветра. </li>
	<li>Записывайте силы баланса и моменты. </li>
	<li>Установите динамическое давление на 7 дюймов H2O.</li>
	<li>Установите угол атаки, начиная с α = -6°. Углы атаки для испытаний α = -6°, -4°, -2°, 0°, 2°, 4°, 6°, 8°, 10°. </li>
	<li>При необходимости отрегулируйте динамическое давление до 7 дюймов H2O и запишите балансовые силы и моменты. </li>
	<li>Повторяйте шаги 2.7 - 2.8, постепенно увеличивая угол атаки, пока не будут выполнены все контрольные точки. </li>
	<li>Возвращаем угол атаки в ноль и устанавливаем угол рысканья. Следующие углы рыскания должны быть испытаны β = 0°, 5°, 10°. </li>
	<li>При необходимости отрегулируйте динамическое давление до 7 дюймов H2O и запишите балансовые силы и моменты. </li>
	<li>Повторяйте шаги 2.10 - 2.11, постепенно увеличивая угол рысканья, пока не будут выполнены все контрольные точки. </li>
	<li>Медленно уменьшите скорость воздуха до нуля, затем заблокируйте внешний баланс. </li>
	<li>Снимите хвостовой конус модели DC-6B и установите хвостовое оперение в сборе. </li>
	<li>Повторите шаги с 2.7 по 2.12. </li>
	<li>Когда все данные будут собраны, выключите систему охлаждения аэродинамической трубы, заблокируйте внешний баланс и выключите аэродинамическую трубу. </li>
</ol>

Испытание малогабаритной модели с использованием аэродинамического баланса в аэродинамической трубе позволяет определить основные аэродинамические характеристики самолета. 6-компонентные весы измеряют три компонента силы: подъемную силу, сопротивление и боковые силы, а также три компонента момента: момент тангажа, рысканья и крена.
Когда достигнуто динамическое сходство между полномасштабным объектом и моделью, например, число Рейнольдса одинаково для случая несжимаемого стационарного потока, ...

Аэродинамические характеристики модели самолета: dc-6b

Источник: Хосе Роберто Морето и Сяофэн Лю, факультет аэрокосмической техники, Государственный университет Сан-Диего, Сан-Диего, Калифорния
Низкоскоростная аэродинамическая труба является ценным инструментом для изучения аэродинамических характеристик самолета и оценки летно-технических характеристик и устойчивости самолета. Используя масштабную модель самолета DC-6B, который имеет съемное хвостовое оперение и 6-компонентный внешний аэродинамический баланс сил, мы можем измерить коэффициент подъемной силы (CL), коэффициент лобового сопротивления (CD), коэффициент момента тангажа (CM), и коэффициент момента рыскания (CN) модели самолета с хвостовым оперением и без него, а также оценить влияние хвостового оперения на аэродинамическую эффективность, продольную устойчивость и путевую устойчивость. 
В данной демонстрации аэродинамические характеристики, летные характеристики и устойчивость самолета анализируются с использованием метода измерения баланса аэродинамических сил. Этот метод широко используется в аэрокосмической промышленности и исследовательских лабораториях для разработки самолетов и ракет. Здесь модель самолета DC-6B анализируется при различных условиях течения и конфигурациях, а также анализируется ее поведение при подверженности резким изменениям.

В ходе этой демонстрации были измерены эксплуатационные характеристики и характеристики устойчивости модели DC-6B в двух конфигурациях. В одной конфигурации к модели крепился обычный самолетный хвост (tail-on), а во второй конфигурации хвост был удален и заменен на конус (tail-off). Для каждой конфигурации определялось изменение коэффициента подъемной силы и коэффициента лобового сопротивления в зависимости от угла атаки (рис. 3). Также было исследовано изменение коэффициента момента танг...

Аэродинамические характеристики модели самолета: DC-6B

Source: Jose Roberto Moreto and Xiaofeng Liu, Department of Aerospace Engineering, San Diego State University, San Diego, CA
The low-speed wind tunnel is ...

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Aeronautical Engineering

Авиационная техника

wind tunnel testing of a dc-6b model

A low-speed wind tunnel can be used to study the aerodynamics of a DC-6B model aircraft. It helps measure how the airplane performs and how stable it is in flight. This type of testing is useful for understanding aircraft behavior under controlled airflow.

The model used here has a removable tail and a 6-component external aerodynamic force balance. That setup lets researchers measure lift coefficient (CL), drag coefficient (CD), pitching moment coefficient (CM), and yaw moment coefficient (CN). These values are compared for the airplane with and without its tail.

The tail’s effect on aerodynamic efficiency, longitudinal stability, and directional stability can then be evaluated. The model DC-6B is tested at different flow conditions and configurations. Its response is also analyzed when it is subjected to sudden changes.

This aerodynamic force balance method is widely used in aerospace industry and research labs. It supports aircraft and rocket development. The demonstration shows how wind tunnel measurements can be used to analyze flight performance and stability in a realistic model airplane.

Wind Tunnel Testing of a DC-6B Model

aerodynamic performance of a model aircraft: the dc-6b

A low-speed wind tunnel can be used to study the aerodynamics of a DC-6B model aircraft. It helps measure how the airplane performs and how stable it is in flight. This type of testing is useful for understanding aircraft behavior under controlled airflow. The model used here has a removable tail and a 6-component external aerodynamic force balance. That setup lets researchers measure lift coefficient (CL), drag coefficient (CD), pitching moment coefficient (CM), and yaw moment coefficient...

propeller characterization: variations in pitch, diameter, and blade number on performance

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Propeller Slip and Blade Design Effects

Propellers are twisted airfoils used to move aircraft and watercraft. The chord angle changes along the radial station of the propeller, which affects how the blade pushes air. Because propellers are important in propulsion systems, engineers study them to help design high-performance vehicles. A key propeller feature is pitch, or twist. Pitch is usually measured as a length and describes the theoretical distance a propeller would move through the air in one full revolution. In real...

airfoil behavior: pressure distribution over a clark y-14 wing

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Measuring Lift with a Clark Y-14 Airfoil

A Clark Y-14 airfoil is used to measure pressure distribution and estimate lift. An airfoil is a 2-dimensional wing section that helps show key wing performance features. In this demonstration, the pressure distribution around the airfoil is measured with a wind tunnel. Pressure distribution is closely related to the lift generated by an airfoil. The Clark Y-14 model used here has a thickness of 14% and a flat lower surface from 30% of the chord length to the back. The model also includes 19...

clark y-14 wing performance: deployment of high-lift devices (flaps and slats)

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Wing Lift Control with Flaps and Slats

The Clark Y-14 wing shows how flaps and slats can change airplane lift during takeoff and landing. A wing is the main part of an airplane that generates lift, and high-lift devices help improve its performance when extra lift is needed. Flaps are located on the trailing edge of the wing. Slats are located on the leading edge. In this experiment, both devices are added to a Clark Y-14 wing so their aerodynamic effects can be studied in a wind tunnel. The wind tunnel creates set airspeeds for...

turbulence sphere method: evaluating wind tunnel flow quality

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Measuring Wind Tunnel Turbulence with a Sphere

Wind tunnel turbulence can be measured with a smooth sphere as a test model. Wind tunnel tests help engineers design vehicles and structures that will face airflow during use. The air flows are applied in a controlled way, and the model is usually a smaller version of the full-sized object. For low-speed wind tunnel tests, the flow around the model must match the flow around the real object as closely as possible. This is called dynamic similarity, and it depends on the Reynolds number. The...

cross cylindrical flow: measuring pressure distribution and estimating drag coefficients

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Cylinder Flow in a Wind Tunnel: Pressure Drag

Cylinder flow in a wind tunnel shows how pressure changes around a circular object and how those changes relate to drag. The lesson focuses on cross cylindrical flow, where air moves across a cylinder and the pressure on its surface is measured. It also compares real fluid behavior with the simpler results predicted by ideal inviscid potential flow theory. For an ideal fluid, the pressure around a cylinder is vertically symmetric. The pressure upstream and downstream of the cylinder is also...

nozzle analysis: variations in mach number and pressure along a converging and a converging-diverging nozzle

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Nozzle Flow Regimes in Converging Nozzles

Nozzle flow changes as the nozzle cross-section changes. A nozzle can accelerate or slow a fluid by shaping the flow path. In aerospace propulsion, nozzles are widely used to help produce thrust. In rockets, propellant leaves the chamber and passes through a nozzle. The nozzle speeds up the propellant and creates a reaction force that moves the system forward. In jet engines, a nozzle converts energy from a high-pressure source into kinetic energy in the exhaust. The flow in a nozzle is...

schlieren imaging: a technique to visualize supersonic flow features

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Supersonic Shock Waves with Schlieren Imaging

Schlieren imaging is used to show shock waves and compression waves in supersonic flow. It helps make air motion visible when the flow becomes compressible. In this demonstration, a Mach 2.0 flow over a cone is examined with a Schlieren system. Military jet fighters and projectiles can travel faster than the speed of sound. The speed of sound is the rate at which a sound wave moves through a medium, and it is 343 m/s. Mach number compares an object’s speed to the speed of sound. An object at...

flow visualization in a water tunnel: observing the leading-edge vortex over a delta wing

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Delta Wing Vortex Flow in a Water Tunnel

Delta wing vortex flow can be studied with a water tunnel and dye visualization. A delta wing is a common wing shape for high-speed airplanes because it performs well in transonic and supersonic flight. It has a small aspect ratio, which means the wing span is short compared with the average chord, and a high sweep angle. These features help reduce drag at high subsonic, transonic, and supersonic speeds. A delta wing also has a high stall angle. Stall happens later than it does for a high...

surface dye flow visualization: a qualitative method to observe streakline patterns in supersonic flow

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Supersonic Surface Flow Patterns with Dye

Supersonic surface flow patterns can be studied with dye flow visualization. This method uses dye on the surface of a body to show how gas moves across it. The resulting streakline patterns help reveal flow paths and surface behavior. Flow visualization is a key tool in aerodynamics research. It helps researchers study flow structure and check ideas about fluid motion. Visualization methods are often grouped into off-the-surface and surface flow techniques. Off-the-surface methods look at the...

pitot-static tube: a device to measure air flow speed

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Measuring Airspeed with Pressure Differences

A Pitot-static tube measures airspeed by comparing air pressure differences. It is widely used to find unknown speeds in airflow, including airplane airspeed. The method relies on Bernoulli's principle, which links changes in pressure to changes in airflow speed. The tube senses stagnation pressure and static pressure. Stagnation pressure is the pressure where the air is brought to rest, and static pressure is the pressure of the moving air around it. The tube connects to a manometer or a...

constant temperature anemometry: a tool to study turbulent boundary layer flow

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Measuring Skin Friction in a Turbulent Boundary Layer

A turbulent boundary layer forms near a solid surface when fluid flow becomes irregular and mixed. In this region, viscous effects and viscous shear stress dominate because friction between the fluid and the surface slows the flow. Outside the boundary layer, the flow is inviscid, which means friction, thermal conduction, and mass diffusion do not create dissipative effects. The boundary layer idea, first introduced by Ludwig Prandtl in 1904, helps simplify the Navier-Stokes equation for flow...

pressure transducer: calibration using a pitot-static tube

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Pitot-Static Pressure Measurement Calibration

Pitot-static pressure measurement calibration uses a wind tunnel, a manometer, and a pressure transducer to link flow pressure to an electrical signal. Fluid pressure is an important flow property for understanding the aerodynamics of a system. In this setup, a pitot-static probe measures stagnation and static pressure during subsonic flow. A U-tube manometer is one of the oldest pressure measurement systems still used today. It is a U-shaped glass tube partly filled with liquid. Because it...

real-time flight control: embedded sensor calibration and data acquisition

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Autopilot Sensors for UAV Flight Control

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multicopter aerodynamics: characterizing thrust on a hexacopter

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Hexacopter Thrust Testing in a Wind Tunnel

Hexacopter thrust testing shows how a six-rotor drone produces lift and drag. Multicopters are popular for hobby and commercial use. They are commonly built as quadcopters, hexacopters, or octocopters, depending on whether they use four, six, or eight thrusters. This study uses a small modular hexacopter platform with propulsion unit redundancy. Redundancy means the vehicle has backup capability if one motor fails. The team first measured static motor thrust with a dynamometer while changing...

aeronautical engineering

This collection introduces fundamental concepts in aeronautical engineering with a focus on methods to evaluate aerodynamic performance, techniques to visualize subsonic and supersonic flow patterns, and procedures to calibrate measurement systems for real-time flight control.

Explore how a DC-6B model aircraft is tested in a low-speed wind tunnel to measure lift, drag, pitching moment, yaw moment, and stability.

Wind Tunnel Testing of a DC-6B Model | JoVE K12

Texas Essential Knowledge and Skills

Physics

PHYS.2

PHYS.2.D

Chemistry and Physics

IPC.2

IPC.2.D

Jose Roberto Moreto

Xiaofeng Liu

Department of Aerospace Engineering

San Diego State University

Concepts

Calibration of Setup

Force Measurements at a Non-zero Windspeed

Results

Position and Displacement

The position of an object defines its location relative to a convenient frame of reference at any particular time. A frame of reference is an arbitrary ...

Average Velocity

To calculate the other physical quantities in kinematics, we must introduce the time variable. The time variable allows us not only to state the position ...

Average Acceleration

The importance of understanding acceleration spans our day-to-day experiences, as well as the vast reaches of outer space and the tiny world of subatomic ...

Instantaneous Acceleration

Acceleration is in the direction of the change in velocity, but it is not always in the direction of motion. When an object slows down, its acceleration ...

velocity-and-position-by-graphical-method

Velocity and Position by Graphical Method

Velocity and position can be calculated from the known function of acceleration as a function of time. The total area under the acceleration-time graph ...

Kinematic Equations - I

When an object moves with constant acceleration, the velocity of the object changes at a constant rate throughout the motion. The kinematic equations of ...

Kinematic Equations: Problem Solving

When analyzing one-dimensional motion with constant acceleration, the problem-solving strategy involves identifying the known quantities and choosing the ...

Force

Forces affect every moment of our life. Our bodies are held to the Earth by force, and they are held together by the forces of charged particles. When we ...

Mass and Weight

Mass and weight are often used interchangeably in everyday conversation. For example,&#160; medical records often show our weight in kilograms, but never ...

Newton's Laws of Motion

Source: Andrew Duffy, PhD, Department of Physics, Boston University, Boston, MA
This experiment examines at various situations involving two interacting ...

Newton's First Law: Introduction

Motion draws our attention. Motion itself can be beautiful, causing us to marvel at the forces needed to create spectacular sights, such as that of a ...

first-law-particles-in-one-dimensional-equilibrium

First Law: Particles in One-dimensional Equilibrium

Newton&#39;s first law of motion states that a body at rest remains at rest, or if in motion, remains in motion at constant velocity, unless acted on by a ...

Newton's Second Law

Newton&#39;s second law is closely related to his first law of motion. It mathematically gives the cause-and-effect relationship between force and changes ...

Force and Acceleration

Source: Nicholas Timmons,&#160;Asantha Cooray, PhD, Department of Physics &#38; Astronomy, School of Physical Sciences, University of California, Irvine, ...

Second Law: Motion under Same Force

Newton&#39;s laws can be applied to bodies at rest and bodies in motion. Newton&#39;s first law is applied to bodies in equilibrium, whereas the second ...

Newton's Third Law: Introduction

Whenever one body exerts a force on a second body, the first body experiences a force equal in magnitude and opposite in direction, to the force that it ...

Drawing Free-body Diagrams: Rules

The first step in describing and analyzing most phenomena in physics involves the careful drawing of a free-body diagram. Free-body diagrams are useful in ...

Free Body Diagrams: Examples

Solving problems that involve forces is easy using free-body diagrams. A free-body diagram is a sketch showing all the external forces that are acting on ...

Equilibrium and Free-body Diagrams

Source: Ketron Mitchell-Wynne, PhD, Asantha Cooray, PhD, Department of Physics &#38; Astronomy, School of Physical Sciences, University of California, ...

Collect, analyze and interpret data regarding the change in motion of an object or system in one dimension, to construct an explanation using Newton’s Laws.

HS.P3U1.6

Solving Problems in Physics

Problem-solving is the ability to apply general physical principles to specific situations, usually expressed by equations. It is an essential skill in ...

Problem Solving in Statics

Problem-solving in statics is a crucial aspect of engineering and physics that involves resolving issues associated with bodies in a state of equilibrium. ...

An Introduction to Mechanics

Humans have been making ships, shelters, pyramids, weapons, agricultural equipment, and many more items without recording the process or theory behind ...

Introduction to Structures

A structure is defined as a system of interconnected members designed to support or transfer forces and successfully withstand the loads acting on them. ...

Simple Trusses

A truss is a structural framework consisting of slender members connected at joints, designed to support external loads while minimizing material usage ...

Method of Joints

The method of joints is a commonly used technique to analyze the forces in structural trusses. The method is based on the principle of equilibrium, which ...

Rigid Body Equilibrium Problems - I

A rigid body is said to be in static equilibrium when the net force and the net torque acting on the system is equal to zero. To solve for rigid body ...

Stability of structures

Consider two rods connected at point O by a pin and a torsional spring of constant k. The ends of both the rods are pin-connected.
If both the rods are ...

Buckling of Steel Columns

Source:&#160;Roberto Leon, Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA
In the design of civil works, it is important ...

Machines

Machines are complex structures consisting of movable, pin-connected multi-force members that work together to transmit forces. One example of a machine ...

DC Motors

Source: Ali Bazzi, Department of Electrical Engineering, University of Connecticut, Storrs, CT. 
The DC machine operates with DC currents and voltages as ...

Rolling Resistance

When a solid cylinder rolls steadily on a rigid surface, the normal force applied by the surface on the cylinder is perpendicular to the tangent at the ...

Propulsion and Thrust

Source: Alexander S Rattner; Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA
Aircraft, rockets, ...

Rocket Propulsion in Empty Space - I

The driving force for the motion of any vehicle is friction, but in the case of rocket propulsion in space, the friction force is not present. The motion ...

Airfoil Behavior: Pressure Distribution over a Clark Y-14 Wing

Source: David Guo, College of Engineering, Technology, and Aeronautics (CETA), Southern New Hampshire University (SNHU), Manchester, New Hampshire
An ...

Use mathematics and computational thinking to explain how Newton’s laws are used in engineering and technologies to create products to serve human ends.

Wind Tunnel Testing of a DC-6B Model

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