TABLE OF CONTENTS 1 INTRODUCTION ......................................................................................................... 1 2 BACKGROUND ........................................................................................................... 2 2.1 main solar collector designs .................................................................................. 3 2.1.1 Flat-plate collectors ........................................................................................... 3 2.1.2 Evacuated tube collectors .................................................................................. 4 2.1.3 Concentrating collectors .................................................................................... 7 2.2 Solar theory ........................................................................................................... 9 2.2.1 Solar radiation.................................................................................................... 9 2.2.2 Sun position relative to the collector surface ..................................................... 9 2.2.3 Two additional angles for special collector designs ........................................ 12 2.3 Collector performance ......................................................................................... 13 2.3.1 Flat-plate collector performance ...................................................................... 13 2.3.2 Evacuated tube collector performance ............................................................ 15 2.3.3 Concentrating collector behaviour ................................................................... 17 3 METHOD .................................................................................................................... 22 3.1 Test methods: From the real collector to its model ............................................. 22 3.1.1 Measurement of the collector performance ..................................................... 22 3.1.2 Installation required for measurements ........................................................... 22 3.1.3 The models ...................................................................................................... 23 3.2 Exploitation of the measured data ....................................................................... 26 3.2.1 A zoom into the Quasi-Dynamic Testing method ........................................... 26 3.2.2 The regression tool .......................................................................................... 28 3.3 Optimization possibilities for the quasi dynamic test method ............................ 33 3.3.1 Dynamic inlet temperature change .................................................................. 33 3.3.2 Increased angular resolution ............................................................................ 35 3.3.3 Night time measurements ................................................................................ 36 4 RESULTS.................................................................................................................... 39 4.1 Theoretical findings for improving the quasi-dynamic test method ................... 39 4.1.1 Dynamic inlet temperature change .................................................................. 39 4.1.2 Higher angular resolution ................................................................................ 44 4.1.3 Night time measurements ................................................................................ 45 4.2 Experimental verification of the theoretical findings .......................................... 52
4.2.1 Dynamic inlet temperature change .................................................................. 52 4.2.2 Higher angular resolution ................................................................................ 55 4.2.3 Night time measurements ................................................................................ 58 5 DISCUSSION ............................................................................................................. 64 6 CONCLUSION ........................................................................................................... 67 NOMENCLATURE .......................................................................................................... 68 BIBLIOGRAPHY .............................................................................................................. 73 A APPENDIX ................................................................................................................... I A.1 Dynamic Inlet Temperature .................................................................................. I A.2 Night time Measurements .................................................................................