The document discusses several aerodynamic concepts related to lift, including:
1. Lift depends on dynamic pressure, coefficient of lift, and wing area. It is generated by differences in pressure between the upper and lower wing surfaces.
2. At higher altitudes, true airspeed must increase to compensate for lower air density in order to maintain the same lift.
3. Wingtip vortices form due to pressure differences across the wing and induce downwash, reducing effective angle of attack and causing induced drag. They can be hazardous to following aircraft.
4. Ground effect reduces drag and increases lift when an aircraft is within one wingspan of the ground due to inhibition of wingtip vort
This Powerpoint Presentation reviews on the topic - Aeroplane and Its Parts (With aerodynamics).
It was made for Educational Purpose.
If anyone want source file, E-mail:- moideenthashreef@hotmail.com
Nomenclature and classification of controls in an airplane (slide # 3-4).
Which are the aerodynamic forces acting on airplane (slide # 5).
Working principle of an airplane (slide # 6).
How an airplane flies (basic motions of an airplane) (slide # 7).
How controls play their roles in these motions (slide # 8-22).
Simulate a flight in Cessna Skyhawk (slide # 23-28).
References and Questions & answers (slide # 30).
This Powerpoint Presentation reviews on the topic - Aeroplane and Its Parts (With aerodynamics).
It was made for Educational Purpose.
If anyone want source file, E-mail:- moideenthashreef@hotmail.com
Nomenclature and classification of controls in an airplane (slide # 3-4).
Which are the aerodynamic forces acting on airplane (slide # 5).
Working principle of an airplane (slide # 6).
How an airplane flies (basic motions of an airplane) (slide # 7).
How controls play their roles in these motions (slide # 8-22).
Simulate a flight in Cessna Skyhawk (slide # 23-28).
References and Questions & answers (slide # 30).
A Good Effect of Airfoil Design While Keeping Angle of Attack by 6 Degreepaperpublications3
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In this document of Theory of Flight
we are discussing some topics in detail which are:
Intereference drag
Induced drag
Factors that Affects Induced Drag:
Stabilator
All these topics are discussed in detail hope you like it................
Density altitude by definition is pressure altitude corrected for non-standard temperature. Well what does that mean? Density altitude is better described as where you airplane feels like it's at. No not where location wise but where altitude wise does it feel like it's at?
This is the presentation on flow past an airfoil . An airfoil-shaped body moving through a fluid produces an aerodynamic force. The component of this force perpendicular to the direction of motion is called lift. The component parallel to the direction of motion is called drag. Subsonic flight airfoils have a characteristic shape with a rounded leading edge, followed by a sharp trailing edge, often with a symmetric curvature of upper and lower surfaces.
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Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
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using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
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Planning Of Procurement o different goods and services
lift force
1. LIFT
LIFT COEFFICIENT AND EQUATION
Lift depends on the following variables
The major factor of which is dynamic pressure. Aerofoil pressure
and AoA det the pressure distribution.
Any Aerodynamic force is the product of these 3 major
factors;dynamic press , coeff of force , surface area.
FORCE= DYN PRESS x FORCE COEFF x SURFACE AREA
2. LIFT
LIFT COEFFICIENT AND EQUATION
LIFT is the result of pressure differential between upper and lower
surfaces for a straight and level flight
Lift formula given as:
TAS & AIR DENSITY
For a given IAS, TAS will vary with altitude owing to air density changes
In ISA density at 40,000ft is a quarter of MSL.
To maintain constant lift as the density reduces, all other elements of the
equation should be changed.
If density drops, the TAS must rise, in this case 2x MSL value
3. TAS & AIR DENSITY
Since the density has dropped by four folds at 40,000ft, we need
to double out airspeed to cater for this.
Maintaining a constant IAS will maintain constant lift.
SPEED AND AoA
If speed rises, Cl must be reduced to maintain the same total lift,
usually by reducing AOA
previous value by reducing alpha to keep lift constant.
4. As all other variables cannot be changed we can have:
If speed is increased in level flight by 30% from the min level
flight Speed (Vs). The new Cl can be calculated as the
percentage of Cl max. speed increase of 30% above can be
written as 1.3 giving 1/1.69 =0.59 = 59%
6. DENSITY COEFFICIENT AND ALTITUDE
VELOCITY used in the dynamic equation speed of the aircraft
relative to the that is moving TAS
IAS = dynamic pressure
At a given AoA a constant Dynamic
pressure must be maintained to
maintain the required lift.
Flying at an alt other than the sea level. With increase in alt ==
decrease in density the TAS increases, if the IAS/dynamic press is
maintained
7. DENSITY COEFFICIENT AND ALTITUDE
Pressure altitude – height above 1013.25mba/hPa
Density altitude is pressure altitude corrected for
temperature deviation.
8. LIFT CURVE
The curve plots Cl against α.
This is the lift curve of a symmetrical aerofoil as it starts at zero lift in
0 AoA.
Cl inc with
AoA upto a
max, Cl max,
at the critical
angle, above
which lift decreases sharply, in a condition known as stall.
To maintain a constant lift force any change in dynamic pressure must be
accompanied by an adjustment in AoA.
9. LIFT CURVE
Min dynamic press V is det by Cl max, which occurs at a
specific AoA, the critical angle 14o-16o.
for an increase in weight a greater speed is required to
maintain lift at a given AOA.
The greater the weight the higher the speed required for
level flight.
10. LIFT CURVE
Lift formula manipulation
Can be used to obtain data that can be used in the lift
formula, eg:
find the stall speed;
given mass-60000kg
gravity-9.81m/s2
density-1.225kg/m3
wing area-105m2
Ans =150kts
This formula can be used to obtain speed for any Cl
11. LIFT/DRAG RATIO
Lift curve of different sections
Thickness-if the thickness of
an aerofoil is increased the
Clmax increases. The red line
represents thickness of 6%
the black line is 12%. The blue
represents a cambered aerofoil
At 00 AoA the aerofoil is producing lift and zero lift is achieved at -40
For a cambered aerofoil.
12. LIFT/DRAG RATIO
the greater the Clmax the lower the Vs (min flight speed)
But the thickness required for the low Vs creates more form drag
and large twisting moment at high speed.
Low Vs leads to low efficient cruise speed coz of excessive drag.
Therefore it is better to use aerofoil that is efficient at high speed
which is able to increase camber at low speed when needed eg on
approach ---- use of flaps.
13. LIFT/DRAG RATIO
Drag aerodynamic force that acts parallel to n in the direction of the RAF
Drag is the product of dynamic pressure, drag coefficient and surface area.
Drag coefficient, Cd, is the ratio of drag per unit wing area to dynamic
pressure.
Drag curve is shown
The efficiency of the
production of lift can be
gauged from studying the
ratio between lift & drag.
A high L/D ratio is more
efficient ie more lift than
drag is produced
The l/d curve is shown below
14. The optimum
AoA for L/Dmax
is about 40.
l/d decreases
until Clmax
L/Dmax occurs
at a specific AoA
the A/C will prod
-uce the least
Possible drag For
the lift required
Any other angle of attack results in a lower L/D ratio which will
increase drag against lift required.
To maintain the 40 AoA any speed can be used depending on the weight
LIFT/DRAG RATIO
15. LIFT/DRAG RATIO
Changes in weight in any given configuration or airframe
contamination state, or at speeds below mach 0.4, will not change
L/Dmax.
Different types of aircrafts L/Dmax.
16. LIFT/DRAG RATIO
Changes in weight in any given configuration or airframe
contamination state, or at speeds below mach 0.4, will not change
L/Dmax.
Different types of aircrafts L/Dmax.
18. EFFECT OF LIFT ON OTHER FACTORS
1. Weight
to maintain a given AoA when weight decreases the airspeed required
to maintain the AoA decreases.
The heavier the aircraft is the higher its Stall speed will be.
The stall speed will be considerably higher at to than on ldg
19. EFFECT OF LIFT ON OTHER FACTORS
2. Condition of the surface
Leading edge roughness can considerably reduce Clmax and thereby
increasing stall speed
This is due to reduction in acceleration over the rough surface===
drop in the pressure differential.
Aft of 20% chord, roughness will have little effect on Clmax or the
lift curve slope. Frost, snow and even rain water can increase
roughness.
Ldg edge icing will cause an unknown increase in stalling speed.
20. EFFECT OF LIFT ON OTHER FACTORS
2. Condition of the surface
21. EFFECT OF LIFT ON OTHER FACTORS
3. Flight at High Lift Conditions
High lift devices like flaps greatly increase Clmax thereby reducing the
min flight speed/(Vs) and thus allow shorter field lengths for T/O n
LDG
22. 3D AIRFLOW
wing terminology
Wing Area- the plan
Surface area of the wing.
Though portion may be
covered by fuselage*
Wing Span-tip-tip dist.
Avg Chord(c)-the geometric
avg.
24. WING TIP VORTICES
Lateral flow over a wing is created by the pressure
differential between upper and lower surfaces.
spanwise flow is induced towards the tips on the lower
surface and towards the roots on the upper surface.
vortices are formed by the crossover of the two spanwise
flow at the trailing edge, and is strongest at the wing tip.
26. WING TIP VORTICES
Induced Downwash
The vertical velocities created by the vortices cause downwash which
results in a reduction in the effective AOA. This continues with increase
in vortex strength
Without vortices, the
lift would be normal to
the free stream airflow,
but with the modified airflow, the lift tilts back creating induced drag
which increases with vortex strength.
28. WAKE TURBULENCE
The high rotational wingtip vortices can be hazardous and are called
wake turbulence.
Vortex generation commences as the nose wheel leaves the ground till
landing.
Exist in every ac including helicopters .
Are maximum in a heavy aircraft in clean configuration at low speed
Weight-the higher the weight the stronger the vortex
Wingspan-shorter influences interference and weakening the 2 vortex
Airspeed- The lower the speed, the stronger the vortex
Configuration- Vortex strength for a given speed and weight is greatest
when ‘clean’
Attitude-the higher the AoA, the stronger the vortices
29. WAKE TURBULENCE
Vortices will stay about ¾ of the wingspan apart, and sink 500-1000ft
Helicopter produces stronger vortices than an aeroplane of the same
weight & speed.
Vortex of a large aircrsfts extend upto 9nm in the air
In still air, vortices will sink to a height 2 wingspan above the ground
then move at above 5kts.
A light crosswind may drift a vortex across a parallel rwy, appch and
climb out, creating a hazard to following aircraft
Vortex disperse with time that’s why we have minimum separation.(ops)
Care should be exercised when approaching a heavier ac especially in
light wind conditions. Always stay above the flight path of preceding ac.
And rotate before it’s lift off point n land beyond its touchdown point
33. GROUND EFFECT
Is the increased lift (force) and decreased aerodynamic drag that an
aircraft's wings generate when they are close to a fixed surface.
When landing, ground effect can give the pilot the feeling that the aircraft is
"floating".
When taking off, ground effect may temporarily reduce the stall speed. The pilot
can then fly just above the runway while the aircraft accelerates in ground effect
until a safe climb speed is reached.
Why is there ground effect??
When an ac is flying at any height significantly higher than it’s own wingspan. The
wing tip vortices is unaffected and the vortex will have norm effect of upwash
before the wing and downwash after the wing
When close to ground i.e. (when height is less than wing span). Vortex generation is
inhibited—reduced upwash n downwash, which alters the effectiveness of the AoA
on wing and tailplane—this is known as ground effect
35. GROUND EFFECT
In ground effect lift will be increased and drag decreased & longitudinal
stability and tailplane pitching moment affected.
Large reduction of Cdi will result when the wing is very close to the ground.
Low wing ac experience a higher ground effect than high wing ac.
Low mounted tailplane will suffer decrease in downwash thereby having a
nose down pitching moment while a high one will be unaffected.
36. GROUND EFFECT
Increasing downwash leads to decrease in tailplane AoA
Decreasing downwash leads to increase in tailplane AoA
37. GROUND EFFECT
Is the increased lift (force) and decreased aerodynamic drag that an
aircraft's wings generate when they are close to a fixed surface.
When landing, ground effect can give the pilot the feeling that the aircraft is
"floating".
When taking off, ground effect may temporarily reduce the stall speed. The pilot
can then fly just above the runway while the aircraft accelerates in ground effect
until a safe climb speed is reached.
Why is there ground effect??
When an ac is flying at any height significantly higher than it’s own wingspan. The
wing tip vortices is unaffected and the vortex will have norm effect of upwash
before the wing and downwash after the wing
When close to ground i.e. (when height is less than wing span). Vortex generation is
inhibited—reduced upwash n downwash, which alters the effectiveness of the AoA
on wing and tailplane—this is known as ground effect
