AN ELECTRONIC CONTROL UNIT DESIGN FOR A MINIATURE JET ENGINE

A THESIS SUBMITTED TO

THE GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES

OF

MIDDLE EAST TECHNICAL UNIVERSITY

BY

CUMA POLAT

IN PARTIAL FULFILLMENT OF THE REQUIREMENTS

FOR

THE DEGREE OF MASTER OF SCIENCE

IN

MECHANICAL ENGINEERING

DECEMBER 2009

Approval of the thesis:

AN ELECTRONIC CONTROL UNIT DESIGN FOR A

MINIATURE JET ENGINE

submitted by CUMA POLAT in partial fulfillment of the requirements for the degree of

Master of Science Mechanical Engineering, Middle East Technical University by,

Prof Dr. Canan ZGEN __________________

Dean, Graduate School of Natural and Applied Sciences

Prof Dr. Sha ORAL _________________

Head of Department, Mechanical Engineering

Asst. Prof. Dr. Melik DLEN _________________

Supervisor, Mechanical Engineering Dept., METU

Examining Committee Members:

Prof. Dr.Kahraman ALBAYRAK ________________

Mechanical Engineering Dept., METU

Asst. Prof. Dr. Melik DLEN ________________

Mechanical Engineering Dept., METU

Prof. Dr. Nafiz ALEMDAROLU ________________

Aerospace Engineering Dept., METU

Asst. Prof. Dr. Bura KOKU ________________

Mechanical Engineering Dept., METU

Asst. Prof. Dr. A. lhan KONUKSEVEN ________________

Mechanical Engineering Dept., METU

Date: 15.12.2009

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I hereby declare that all information in this document has been obtained and presented

in accordance with academic rules and ethical conduct. I also declare that, as required

by these rules and conduct, I have fully cited and referenced all material and results

that are not original to this work.

Name, Last Name: Cuma POLAT

Signature :

iv

ABSTRACT

AN ELECTRONIC CONTROL UNIT DESIGN FOR A

MINIATURE JET ENGINE

POLAT, Cuma

MS., Department of Mechanical Engineering

Supervisor: Asst. Prof. Dr. Melik DLEN

December 2009, 139 pages

Gas turbines are widely used as power sources in many industrial and transportation

applications. This kind of engine is the most preferred prime movers in aircrafts, power

plants and some marine vehicles. They have different configurations according to their

mechanical constructions such as turbo-prop, turbo-shaft, turbojet, etc. These engines have

different efficiencies and specifications and some advantages and disadvantages compared to

Otto-Cycle engines. In this thesis, a small turbojet engine is investigated in order to find

different control algorithms.

AMT Olympus HP small turbojet engine has been used to determine the mathematical model

of a gas turbine engine. Some important experimental data were taken from AMT Olympus

engine by making many experiments. All components of the engine have been modeled by

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using laws of thermodynamics and some arithmetic calculations such as numerical solution

of nonlinear differential equations, digitizing compressor and turbine map etc. This

mathematical model is employed to create control algorithm of the engine. At first, standard

control strategies had been considered such as P (proportional), PI (proportional integral),

and PID (proportional-integral-differential) controllers. Because of the nonlinearities in gas

turbines, standard control algorithms are not commonly used in literature. At the second

stage fuzzy logic controllers have been designed to control the engine efficiently. This

control algorithm was combined with mathematical of the engine in MATLAB environment

and input-output relations were investigated. Finally, fuzzy logic control algorithm was

embedded into an electronic controller.

Keywords: Turbojet, Modeling, Control, Fuzzy Logic

vi

Z

KK BR JET MOTORU N ELEKTRONK KONTROL

NTES TASARIMI

POLAT, Cuma

Yksek Lisans, Makina Mhendislii Blm

Tez Yneticisi: Yrd. Do. Dr. Melik DLEN

Aralk 2009, 139 sayfa

Gnmzde kk gaz trbin motorlar, model uaklarda, elektrik retim tesislerinde,

insansz hava aralarnda, dronlarda ve benzeri hava platformlarnda sklkla

kullanlmaktadr. Bu motorlar turbo-prop, turbo-aft, turbo jet gibi farkl kombinasyonlarda

kullanlabilmektedir. Gaz trbin motorlar g/boyut ilikisi dikkate alndnda olduka

byk avantajlara sahiptir. Yksek yakt tketimi ise motorlarn dezavantajlar arasnda

saylabilmektedir. lkemizde de son zamanlarda farkl alanlarda kullanlmaya balanan bu

motorlarn verimli ve gvenli bir ekilde kontrol edilebilmesi almamzn ana konusunu

oluturmaktadr.

Bu almamzda ncelikle AMT Olympus HP gaz trbin motoru iin matematik model

oluturulmutur. Kodun oluturulmas aamasnda gereken teknik veriler ve test deerleri

yine benzer motor ile yaplan testlerden elde edilmitir. Her bir para modellenerek motorun

MATLAB ortamnda termodinamik yasalar kullanlarak tm modeli oluturulmutur.

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Oluturulan matematik model kullanlarak motorun kontrol algoritmas gelitirilmi. Bu

aamada oransal, oransal-tmlevsel ve oransal-tmlevsel-trevsel kontrolcler tasarlanmaya

allm fakat motorun dorusal olmayan yaps gz nnde bulundurularak bulank mantk

algoritmas oluturulmutur. Tasarlanan bulank mantk algoritmas motorun matematik

modeli ile birletirilerek eitli girdilere karlk motorun davran incelenmitir. Son

aamada ise oluturulan bulank mantk algoritmas dsPIC30F4013 mikroilemcisine

gmlerek motorun kontrol salanmtr.

Anahtar Kelimeler: Turbojet, Modelleme, Kontrol, Bulank Mantk

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ACKNOWLEDGMENTS

I am deeply grateful to my thesis Supervisor Asst. Prof. Dr. Melik Dlen his guidance,

advice, criticism, encouragement and insight throughout the research. I would also like to

thank to Prof. Dr. Nafiz Alemdarolu for his suggestions, comments, helps. Special thanks

to my friend alar Atalayer and Murat Ceylan for their assistance on my experiments and

study.

I am grateful to my family, lyas Polat, Fikriye Polat and Dilek Polat and to my love Bahar

Sarkaya for their endless love, support, trust and encouragement. This work has been

supported by METU Microjet Project directed by Prof. Dr. Nafiz Alemdarolu in Aerospace

Engineering Department.

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TABLE OF CONTENTS

ABSTRACT ............................................................................................................................ iv

Z ........................................................................................................................................... vi

ACKNOWLEDGMENTS .................................................................................................... viii

TABLE OF CONTENTS ........................................................................................................ ix

LIST OF TABLES ................................................................................................................. xii

LIST OF FIGURES .............................................................................................................. xiii

LIST OF SYMBOLS ............................................................................................................ xvi

CHAPTERS

1. INTRODUCTION ........................................................................................................... 1

2. REVIEW OF THE STATE OF THE ART ...................................................................... 4

2.1 Introduction .......................................................................................................... 4

2.2 Gas Turbine Engine Control ................................................................................ 4

2.3 Engine Control Programs ..................................................................................... 5

2.4 Mathematical Modeling ....................................................................................... 7

2.4.1 Mathematical Modeling of Gas Turbine Engines ........................................ 7

2.4.1.1 Mathematical Model of the Compressor .................................................. 9

2.4.1.2 Mathematical Model of the Combustion Chamber ................................ 11

2.4.1.3 Mathematical Modeling of the Turbine ................................................. 12

2.4.1.4 Gas Turbine Computer Simulation ........................................................ 15

2.4.1.5 Simulation Results ................................................................................. 17

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2.4.2 Some Important Studies about Modeling, Simulation and Control of Gas

Turbine Engines ................................................