Engine SystemsProblem 1: Modeling of an Intake Manifold

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Important notes 1/3

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Structure of the exercises – a reminder

Theory Exercises

Assigments 1-6

Matlab/Simulink Exercises

Intake Manifold

Exercise

Idle Speed Control

Exercise

Week 1-3

Week 4-13

The intake

manifold

prepares you

very well for

the much more

complex ISCS-

Exercise!

Important notes 2/3

02.10.2017 3ETH Zurich - DMAVT - IDSC www.idsc.ethz.ch

You do not have to hand in any material for the intake

manifold exercise.

Feel free to hand in a little report on October 13 which we

will proofread. This is to make sure you know what you are

doing before we start the idle speed control exercise.

We will discuss intermediate steps in each exercise class

and recommend you solve these tasks within the following

week.

Important notes 3/3

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Theory sheet #2 is online

Complete sheet #1 by October 9th

Complete sheet #2 by October 23th

Intake Manifold Exercise Part 2

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So far: You should have created a working

Simulink model

Data: «Manifold Identification Data» from the webpage

Intake Manifold Exercise Part 2

So far: You should have created a working

Simulink model

Data: «Manifold Identification Data» from the webpage

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Ugly layout Hard to debug

Nice layout

much easier to debug

Intake Manifold

Exercise Part 2

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Helpful blocks: Goto

Simulink/Signal Routing

From

Simulink/Signal Routing

Fcn

Simulink/ User-Defined Functions

Intake Manifold Exercise Part 2

Still to come:

Parameter Identification (task of this week)

Linearization/Normalization (task of next week)

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General remarks There are many approaches to do a parameter identification

Different approaches often differ substantially in their efficiency

We use fminsearch, a Matlab-function that minimizes a user-defined cost function.

Very easy to use

Can be used to solve a large class of problems

Well suited for the given problem

Generally very inefficient

Parameter Identification using fminsearch

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Task for this week

Parameter Identification using fminsearch

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Study the files in ParIdDemo.zip on the webpage

Task for this week

Download «Manifold Identification Data» from the webpage

Normalize & Linearize the nonlinear model

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Define nominal input

Equilibrium point: run your model with nominal inputs

until it reaches steady-state conditions and choose these

values as equilibrium around which you want to linearize

your model

Use the command linmod to perform the linearization

Theory behind normalizing/linearizing can be found in the

exercise instructions

Task for next week

Compare the system response of the linearized

and normalized model with the nonlinear model

Task for next week

A, B, C, D Matrices

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Just do it!