Aims

The aims of the course are to:

• analyse and solve a range of practical engineering problems associated with acoustics.

Objectives

As specific objectives, by the end of the course students should be able to:

• understand what sound is and how we perceive it
• understand how sound is generated and propagated
• understand the acoustics of a wide range of music and noise production

Content

We will analyse and solve a range of practical engineering problems associated with acoustics. Examples include modelling of noise sources from jets, fans, musical instruments, human voice, kettles, dripping taps, whistling mice, singing flames, etc. We will also study ways to reduce noise either at the source or through acoustic damping. Upon completion of this module, the students would be well placed to pursue academic research in the area of acoustics and related fields or to work in industry (the topics covered in the course is of interest to GE, Rolls-Royce, Airbus, Dyson, Mitsubishi Heavy Industries, automotive companies, music industry, and acoustic consultancies).

What is sound and how does it propagate? (5L) (Dr A Gregoryl)

• Introduction
• The wave equation
• Some simple 3D wave fields (plane waves, surface waves and spherical waves)
• Sound transmission through different media

Simples sounds sources (2L) (Dr A Agarwal)

• Pulsating sphere
• Oscillating sphere
• Example: loudspeaker with and without a cabinet

General solution to wave eqn (2L) (Dr. A Gregory)

• Green's function
• Sound from general mass and force sources (examples, Bliz siren and singing telephone wires)

Jet noise (Dr A Agarwal) (1 L)

• Scaling of jet noise. How much does jet noise increase by if we double the jet's velocity?
• What do jets and tuning forks have in common?
• Lighthill's acoustic analogy
• Sound of aircraft jets and handdriers 

Duct acoustics (2 L) (Dr A Agarwal)

• Rectangular ducts (example, sound box)
• Low-frequency sound in ducts
• Circular ducts
• Acoustic liners (Helmholtz resonator, blowing over a beer bottle)

Musical acoustics & everyday things (3L) (Drs A Agarwal and A Gregory)

• String instruments 
• Wind instruments 
• Brass instruments 
• Whistling of steam kettles and Rayleigh's Bird Call
• Acoustics of dripping taps

Vocalisation (0.5 L) (Dr A Gregory)

• Human speech, singing and overtone singing
• Mice mating calls

Fan noise (1L) (Dr A Agarwal)

• Rotor alone noise
• Rotor-stator interaction noise

Thermoacoustics instability (0.5 L) (Dr A Agarwal)

• Rijke tube experiment (singing flames)

This syllabus contributes to the following areas of the UK-SPEC standard:

Toggle display of UK-SPEC areas.

 
Last modified: 01/09/2020 10:25

Aims

The aims of the course are to:

• analyse and solve a range of practical engineering problems associated with acoustics.

Objectives

As specific objectives, by the end of the course students should be able to:

• understand what sound is and how we perceive it
• understand how sound is generated and propagated
• understand the acoustics of a wide range of music and noise production

Content

We will analyse and solve a range of practical engineering problems associated with acoustics. Examples include modelling of noise sources from jets, fans, musical instruments, human voice, kettles, dripping taps, whistling mice, singing flames, etc. We will also study ways to reduce noise either at the source or through acoustic damping. Upon completion of this module, the students would be well placed to pursue academic research in the area of acoustics and related fields or to work in industry (the topics covered in the course is of interest to GE, Rolls-Royce, Airbus, Dyson, Mitsubishi Heavy Industries, automotive companies, music and biomedical industries, and acoustic consultancies).

What is sound and how does it propagate? (5L) (Dr A Agarwal)

• Introduction
• The wave equation
• Some simple 3D wave fields (plane waves, surface waves and spherical waves)
• Sound transmission through different media

Simples sounds sources (2L) (Dr A Agarwal)

• Pulsating sphere
• Oscillating sphere
• Example: loudspeaker with and without a cabinet

General solution to wave eqn (2L) (Dr. A Agarwal)

• Green's function
• Sound from general mass and force sources (examples, Bliz siren and singing telephone wires)

Jet noise (Dr A Agarwal) (1 L)

• Scaling of jet noise. How much does jet noise increase by if we double the jet's velocity?
• What do jets and tuning forks have in common?
• Lighthill's acoustic analogy
• Sound of aircraft jets and handdriers 

Duct acoustics (2 L) (Dr A Agarwal)

• Rectangular ducts (example, sound box)
• Low-frequency sound in ducts
• Circular ducts
• Acoustic liners (Helmholtz resonator, blowing over a beer bottle)

Musical acoustics & everyday things (3L) (Drs A Agarwal)

• String instruments 
• Wind instruments 
• Brass instruments 
• Whistling of steam kettles and Rayleigh's Bird Call
• Acoustics of dripping taps

Vocalisation (0.5 L) (Dr A Agarwal)

• Human speech, singing and overtone singing
• Mice mating calls

Fan noise (1L) (Dr A Agarwal)

• Rotor alone noise
• Rotor-stator interaction noise

Thermoacoustics instability (0.5 L) (Dr A Agarwal)

• Rijke tube experiment (singing flames)

This syllabus contributes to the following areas of the UK-SPEC standard:

Toggle display of UK-SPEC areas.

 
Last modified: 21/05/2021 13:24

Aims

The aims of the course are to:

• introduce students to fundamental combustion concepts, and their influence on internal combustion engine preformance and emissions.

Objectives

As specific objectives, by the end of the course students should be able to:

• Understand fundamental concepts in combustion
• Understand combustion issues particularly relvant to gas turbines
• Understand the performance and efficiency characteristics of IC engines
• Understand the formation and aftertreatment of pollutants in IC engines, and tradeoffs with performance

Content

Chemical thermodynamics and equilibrium (1L)

Conservation laws for multicomponent mixture, multispecies equilibrium and calculation method

Chemical kinetics (1L)

Principles of chemical kinetics – law of mass action, activation energy, order & degree of a reaction, hydrocarbon reaction chains
, pollutant formation 
multistep reactions, chemical explosion, chemistry reduction using steady state and partial equilibrium approximations

Applications of chemical kinetics: limit reators (1L)

Common approximations used in combustion analysis – perfectly stirred reactor, plug flow reactor, thermal explosions, autoignition & spark ignition

Laminar premixed flames (1L)

Concepts and measurements,
 conservation equations in one and multiple dimensions, characteristic time and space scales, Zeldovich number, solution for 1D flame, flame speed and its dependence on mixture composition, temperature and pressure

Laminar non-premixed flames (1L)

Mixture fraction concept and its physical significance, conserved scalar approach, state relationship, simple solution for diffusion flame, droplet combustion as an example for diffusion flame

Pollution from Combustion (1L)

Nature of pollution emitted by combustion and its effect on environment & human health, features of pollution generation chemistry, typical techniques used for emission reduction

Turbulent Combustion (1L)

A brief introduction to turbulent combustion, its importance, applications, and scientific methods used to study turbulent combustion

Introduction to Internal Combustion Engines (1L)

Types of engines – Spark Ignition Engines, Diesel Engines, Homogeneous Charge Compression Ignition (HCCI) Engines; Thermodynamic cycles and Efficiency; Emissions control

Outlook for Energy and Transport (1L)

Transport energy outlook – drivers for change, prospects for alternatives to internal combustion engines and conventional fuels, challenges of full electrification, importance of internal combustion engines and the necessity and potential for improving them

Practical Transport Fuels (1L)

Composition, properties, manufacturing, & specifications

Deposits in Engines and Fuel Additives (1L)

Fuel system, intake system and combustion chamber deposits in SI engines, diesel injector deposits in diesel engines, mechanisms of formation, effects on engine performance and operation, controlling methods

Fuel Anti-Knock Quality and Knock in SI Engines (1L)

Knock and SI engine performance, fuel antiknock quality, RON, MON and octane index, lessons learnt from HCCI studies, future fuel requirements

Insights into knock onset, knock intensity, superknock and preignition (1L)

Knock fundamentals, ignition delay and Livengood-Wu integral, stochastic nature of knock, knock intensity, developing detonation and superknock, difference between preignition and superknock, application of fundamental insights to practical understanding

Fuel effects in compression ignition engines (1L)

Particulate/NOx control and ignition delay, Gasoline Compression Ignition (GCI) engines, fuel effects, advantages, challenges and prospects for GCI, dual fuel approaches to low NOx/low soot combustion

Evolution of future transport energy and implications for future fuels (1L)

Summary of previous 7 lectures. Future fuels and engines

This syllabus contributes to the following areas of the UK-SPEC standard:

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Last modified: 19/03/2019 14:43

Aims

The aims of the course are to:

• develop the basic ideas necessary to understand some advanced concepts in aerodynamics.
• cover the aerodynamic effects that constrain an aircraft design.

Objectives

As specific objectives, by the end of the course students should be able to:

• have an appreciation of the aerodynamic factors likely to feature in the designs of new aircraft.
• have an understanding of the behaviour of boundary layers over swept wings in compressible flow.
• estimate the position of laminar-turbulent transition.
• estimate wing drag, and to be familiar with techniques for avoiding turbulent flow.
• have sufficient knowledge to be able to predict the different supersonic zones on a wing.
• understand how the basic physics can be integrated into the design of an aircraft.
• understand how to make design trade-offs.
• have a basic appreciation of the impact of aviation on the environment and possible responses.

Content

This course aims to develop the basic ideas necessary to enable the student to understand some advanced concepts in aerodynamics. In particular the course will cover the aerodynamic effects that constrain an aircraft design. The course will highlight those factors determining the configuration of aircraft for different duties relating them to the effect of compressibility at transonic speeds, the control of boundary layers to benefit from laminar flows and the estimation of aerodynamic loads on the aircraft structure. Coursework will illustrate basic physics, via transonic airfoil design and the integration of these basics via a study of the trade-offs made in producing a design for a given specification. The course will end by reviewing the environmental impact of aviation and show how aircraft design might change to reduce this impact.

Introduction to transonic wings (3L, Dr J P Jarrett)

• Review of 3A3 material: boundary layers and drag estimation;
• Transonic flow about two-dimensional aerofoils;
• Shock-boundary layer interaction;
• Supercritical aerofoils with delayed shock-induced drag rise.

Transonic aerofoil design (4h coursework, Dr J P Jarrett)

This coursework section will allow the interactive design of a transonic aerofoil profile on a workstation in the DPO. The aim is to consolidate the lecture material and illustrate how the various design constraints compete in practice.

Advanced aerodynamics (3L, Dr J P Jarrett)

• Aerodynamic challenges of high-speed flight
• Airframe/Intake integration
• Stability of swept wing aircraft
• Practical swept wing design
• Delta and slender ogival wings
• Vertical / short take-off and landing

Aviation and the environment (6L, Prof CA Hall)

The impact of air transport on the environment; the relationship between technology, operational practice, regulation and economics.

• Basic modelling
• The environment - overview of atmospheric chemistry, fluid dynamics & mixing; the greenhouse effect; radiative forcing.
• Airframe - aircraft range & endurance, the Breguet equation; ML/D payload, fuel and structure weight; choice of fuel. Why do airplanes fly at the altitude they do? Payload and fuel efficiency.
• Engine - simple modelling of a high-bypass ratio turbofan engine. Cycle efficiency and propulsive efficiency, trading production of NOx and CO2.
• What would an airplane look like if optimised to reduce environmental impact?

Greener by Design (Coursework, Prof CA Hall)

The coursework consists of a choice of one from three case studies, based on the simple modelling above to study from the perspective of environmental impact the trade-offs associated with (A) design range;(B) cruise altitude;and (C) engine overall pressure ratio. It is intended that the case studies will be spreadsheet based.

This syllabus contributes to the following areas of the UK-SPEC standard:

Toggle display of UK-SPEC areas.

 
Last modified: 12/09/2024 15:22