The Aerodynamics of the Aircraft (Chapter 2) Động lực học hàng không của máy bay

1. Introduction Turbine Engines (Ch. 1) – The Atmosphere2. The Aerodynamics of the Aircraft (Ch. 2) – Specific Fuel Consumption3. The Creation of Thrust in a Jet Engine (Ch. 3) – Newton’s Second Law4. Gas Turbine Principles (Ch. 4) – Diagrams of Temperature – Entropy 5. The Gas Turbine Efficiency (Ch. 4) – Thermal and Cycle Efficiency 6. The Principle and Layout of Jet Engine (Ch. 5) – Turbine Inlet Temperature7. Fluid Mechanics of Compressible Gases (Ch. 6) – Energy Equation8. Fluid Mechanics of Compressible Gases (Ch. 6) – Mass Flow per Unit Area9. Selection of Bypass Ratio (Ch. 7) – Jet Velocity and the Fan Pressure Ratio10. Selection of Bypass Ratio (Ch. 7) – Bypass Ratio for Minimum Specific Fuel Consumption11. Dynamic Scaling and Dimensional Analysis (Ch. 8) – Nondimensional Treatment of Thrust12. Turbomachinery: Compressors and Turbines (Ch. 9) – Flow Coefficient and Work Coefficient13. Turbomachinery: Compressors and Turbines (Ch. 9) – Axial Turbine and Axial Compressor14. Overview of the Civil Engine Design (Ch. 10) 15. CFM56 Engines

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Turbine Engines - Week 2: Động lực học hàng không của máy bay - Động cơ tua-bin khí 1

Tuần 2 – The Aerodynamics of the Aircraft (Chapter 2)

Động lực học hàng không của máy bay

1 Large Aircraft

2 Sizing the Wing

3 Lift, Drag, Fuel Consumption and Range

4 Breguet Range Equations - Specific Fuel Consumption

5 Selecting the Engine Thrust

6 Engine Weight and Fuel Consumption

Các nội dung chính của môn học (15 tuần theo textbook)

1 Introduction - Turbine Engines (Ch 1) – The Atmosphere

2 The Aerodynamics of the Aircraft (Ch 2) – Specific Fuel Consumption

3 The Creation of Thrust in a Jet Engine (Ch 3) – Newton’s Second Law

4 Gas Turbine Principles (Ch 4) – Diagrams of Temperature – Entropy

5 The Gas Turbine Efficiency (Ch 4) – Thermal and Cycle Efficiency

6 The Principle and Layout of Jet Engine (Ch 5) – Turbine Inlet Temperature

7 Fluid Mechanics of Compressible Gases (Ch 6) – Energy Equation

8 Fluid Mechanics of Compressible Gases (Ch 6) – Mass Flow per Unit Area

9 Selection of Bypass Ratio (Ch 7) – Jet Velocity and the Fan Pressure Ratio

10 Selection of Bypass Ratio (Ch 7) – Bypass Ratio for Minimum Specific Fuel Consumption

11 Dynamic Scaling and Dimensional Analysis (Ch 8) – Non-dimensional

3

Largest Jet Engine in the world (2017) is the General Electric’s GE90-115B which has a maximum diameter of 3.4 meters It generates 115,300 pounds of thrust and is currently the biggest and most powerful turbofan engine in the world These big engines can be found on Boeing 777 models.

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JFK Airport, New York, 2017

1 Large Aircraft

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Boeing 777-9X with 2 engines

Four or two engines?

The A380 is to have four engines, two stung under each wing and the same arrangement is adopted for the New Large Aircraft

Not long ago it would have been unthinkable to have a trans-oceanic aircraft with only two engines because reliability of the engines was

inadequate Now two-engine aircrafts are very common, being the

dominant type now crossing the Atlantic, but four engines offer

advantages for the New Large Aircraft for two reasons

First, every aircraft must be able to climb from takeoff with one engine totally disabled For a two-engine aircraft this means that there must be twice as much thrust available at takeoff as that just necessary to get the aircraft safely into the air The engines must be oversized for

takeoff, implying too much available thrust at cruise (and therefore

excess weight) with the engines ‘throttled back’ For a four-engine

aircraft the same rule requires that there is only 4/3 times as much

thrust available at takeoff, and for the aircraft designed for very long

flights it is desirable to carry as little surplus weight as possible

The success of the Boeing 777 as a very long range aircraft hasundermined this argument in recent years; as is discussed in later chaptersthe apparent disadvantage with two engines can be mitigated by cruising athigher altitude and the benefits in reduced first cost and maintenance costcompensates for a small increase in fuel consumption.

The second reason for having four engines is that it is not consideredpractical to make the wing much higher off the ground than current aircraftlike the 747-400, since to do so would raise the cabin and if the cabin wereraised higher, the existing passenger handling facilities at airports would beunusable; it would also make the undercarriage much bigger and heavier Ifthe New Large Aircraft, or the Airbus A380, were to have only two enginesthese would be too large to fit under the wings at their current height fromthe ground It should be added in parenthesis, however, that becauseengines are expensive to buy and to maintain it is likely that smaller aircraftthan the New Large Aircraft we are considering here will have only twoengines, even when they are to be operated over large distances Recentexamples are the Airbus 330 and the Boeing 777; both of these large twinsare used for flights that are sufficiently long that until recently a four-engineaircraft would have been needed

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2 Sizing the Wing (for Lift = Weight)

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3 Lift, Drag, Fuel Consumption and Range

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4 Breguet Range Equations - Specific Fuel Consumption

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5 Selecting the Engine Thrust

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6 Engine Weight and Fuel Consumption

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TURBOFAN ENGINES

Engine Core

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TURBOFAN ENGINES

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3 The Creation of Thrust in a Jet Engine (Ch 3) – Newton’s Second Law

Nguyên lý lực đẩy của động cơ phản lực

• Làm bài tập - Exercises of Chapter 2

• Làm bài tập - Exercises of Chapter 2