Ship Resistance and Propulsion

Learning Outcomes

Knowledge and Understanding

Having successfully completed this module, you will be able to demonstrate knowledge and understanding of:

• Select a main engine and analyse propeller engine matching.
• Design of a propeller for a given operation.
• Predict the delivered power of a ship or marine vehicle.
• Estimate the components of propulsive efficiency.
• Assess the operation of marine propulsion devices.
• Calculate the resistance of a ship or marine vehicle.
• Identify the components of ship resistance.

Transferable and Generic Skills

Having successfully completed this module you will be able to:

• Use small-scale physical models to deduce full-scale quantities through a combination of testing and analysis based on first principles.
• Use simple mathematical models, computational tools and empirical evidence to derive engineering estimates of physical quantities.
• Evaluate alternative models (e.g. analytical, computational, and physical) to determine the most appropriate for solving a specified engineering task.

Subject Specific Intellectual and Research Skills

Having successfully completed this module you will be able to:

• Design propeller and select engine to fulfil the service requirements of ship or marine vehicle.
• Analyse the powering requirements of a ship or marine vehicle based on your understanding of the physical nature of the fluid flow around the vessel.

Subject Specific Practical Skills

Having successfully completed this module you will be able to:

• Use your understanding of a marine propeller in order to carry out a simple propeller design.
• Apply your knowledge of the components of propulsive efficiency to estimate the delivered power of a ship or marine vehicle.
• Apply your understanding of the physical components of ship resistance to estimate the resistance of a ship or marine vehicle.

Learning Outcomes

Having successfully completed this module you will be able to:

• C1/M1 In the course work assignments and exam paper questions, the students must demonstrate their ability and skills in applications of mathematical tools and physical laws underlining the breakdown of ship resistance components and the developments of the scaling procedures for the full scale ship resistance from the model test data. C2 In propeller design process in the course work assignment and exam questions, the students need to analyse the given question and, based on their understanding of the propeller charts, derive a set of suitable propeller parameters for given propeller working condition. C3/M3 To complete the power estimation and propeller design assignment, the students need to select appropriate data sets and solution methods available from the design software and carry out the necessary calculations and then discuss the related outcome from the software tools. C5 In individual propeller design assignment, the ship particulars and associated parameters are given and the students must derive suitable propeller work condition parameters taking consideration for both cavitation and efficiency using design software. The analysis at off-design working performance is also required. C12/M12 The resistance lab requires the students to make use of the state-of-art towing tank and associated data acquisition system to obtain data for the scaled model of a ship and the outcome is submitted for assessment in a group report. C13 For the resistance lab, the students need to undertake the model set up process and the calibration of the data acquisition system. During the lab, the multiple speed runs are conducted and the students need to process the data and discuss the associated errors. C16 The resistance lab is carried out in groups of 3 or 4 students and the assessment is via a group report. By completion of lab running and report production, the students demonstrate how they have worked effectively as individuals as well as a member of a team.

General introduction to ship resistance and propulsion and definitions.

• Physical components of ship resistance.
• Dimensional analysis and scaling.
• Practical scaling methods: CT = CF + CR and CT = (1+k) CF + CW
• Systems of coefficients used in ship powering.
• Boundary layer and friction.
• Flat plate friction formulae: Froude, Schoenherr and I.T.T.C.
• Geosim series: description and applications.
• Wave resistance: general principles: wave system interference and cancellation.
• Standard series data: Taylor-Gertler, BSRA series - description and applications; references to other series.
• Regression analysis techniques: discussion and references.
• General survey of propulsion devices.
• Definitions and brief description of the components of propulsive efficiency.
• Marine propeller geometry and design parameters.
• Dimensional analysis and propeller coefficients.
• Standard series propeller design charts:KT-KQ; description, applications and examples.
• Cavitation: outline of origins and effects; preliminary cavitation criterion and choice of blade area ratio.
• The analysis of wake: self-propulsion tests and derivation of wT, t, nR and QPC.
• Overview of main engine selection considerations.
• Introduction to ship power train components. Stern tubes, shafts, bearings.
• Propeller engine matching.

Teaching methods include

• Lectures, tutorials,
• Two labs in towing tank
• One ship powering assignment

Learning activities include

• Self-learning through reading and study
• Directed problem solving exercises
• Ship resistance experiment in a towing tank
• Propeller open water test in a towing tank
• Report writing for the labs and course work assignment

Summative

This is how we’ll formally assess what you have learned in this module.

Referral

This is how we’ll assess you if you don’t meet the criteria to pass this module.

Repeat

An internal repeat is where you take all of your modules again, including any you passed. An external repeat is where you only re-take the modules you failed.