UNIVERSITÀ DI PISA
FACOLTÀ DI INGEGNERIA
Tesi di Laurea Specialistica in Ingegneria Aerospaziale
Development of a non-intrusive technique
for temperature and concentration measurements
in a liquid
Relatori: Candidata:
Prof. Giovanni Lombardi Simonini Alessia
Prof. Patrick Rambaud Dr. Maria Rosaria Vetrano
Research is what I’m doing when I don’t know what I’m doing.
Contents
Contents i Nomenclature iii Introduction v 1 Literature survey 1 1.1 Droplet investigation . . . 1 1.2 Jet investigation . . . 41.3 Other kinds of flow . . . 6
2 Technique principle and mathematical model 7 2.1 Principle . . . 7
2.1.1 Absorption . . . 7
2.1.2 Energy conversion and emission . . . 7
2.1.3 Organic dye . . . 8
2.2 Technique . . . 10
2.3 Mathematical model . . . 11
2.4 Data inversion algorithm . . . 13
2.4.1 1-color LIF . . . 14
2.4.2 2-color LIF . . . 14
3 Data processing 17 3.1 Development of a matlab routine . . . 17
3.1.1 Temperature calibration . . . 17 3.1.2 Processing . . . 18 3.1.3 Post-processing . . . 19 4 Experimental Methodology 21 4.1 Considerations . . . 21 4.2 Non-intrusiveness of technique . . . 21 4.3 Temperature calibration . . . 24 4.4 Camera calibration . . . 29 i
4.4.1 Dark and background image . . . 30 4.4.2 Camera alignment . . . 30 5 Experimental set-up 33 5.1 Introduction . . . 33 5.2 PLIF facility . . . 33 5.3 Cell facility . . . 35 5.4 Spray facility . . . 36 6 Results 40 6.1 Introduction . . . 40
6.2 Uniform temperature cell investigation . . . 40
6.2.1 1-C and 2-C PLIF measurement dependence on laser energy . . . 40
6.2.2 Temperature results . . . 45
6.2.3 Concentration results . . . 48
6.3 Spray temperature investigation by 2-C PLIF . . . 49
7 Conclusions and further investigations 61 7.1 Conclusions . . . 61
7.2 Further investigations . . . 62
Appendix 64 A Matlab© Graphic User Interface routine 65 B Components information 83 B.1 Optical components . . . 83
B.1.1 Filters . . . 83
B.1.2 Spectrometer HR4000 . . . 85
B.1.3 Laser Solo PIV I-15 . . . 86
B.1.4 Imager intense CCD camera . . . 88
B.1.5 Objectives . . . 90
B.2 Mechanical components . . . 91
B.2.1 Pump IWAKI MD70RV(M) . . . 91
B.2.2 UniJet fullcone nozzle TGSS1 . . . 93
C Preliminary accuracy study of β 94
D Camera alignment procedure 95
References 99
List of figures 102