Flow Boiling in Expanding Microchannels

Chapter 1: Introduction1.1Background1.2Objectives      ReferencesChapter 2: Flow Boiling Heat Transfer and Pressure Drop Characteristics in Expanding Microgap Channel2.1Experimental Setup and Procedure<2.2Bubble characteristics in flow boiling expanding microgap heat sink2.3Comparison of pressure drop between expanding microgap heat sinks2.4Comparison of boiling curves between expanding microgap heat sinks2.5Comparison of local flow boiling heat transfer coefficient between expanding microgap heat sinks2.6Comparison of microgap heat transfer coefficient data with literature2.7Comparison of wall temperature uniformity between expanding microgap heat sinks2.8Conclusions     ReferencesChapter 3: Flow Boiling Instabilities in Expanding Microgap Channel3.1Mass flux effects on flow boiling instabilities in expanding microgap channel3.2Heat flux effects on flow boiling instabilities in expanding microgap channel3.3Microgap size effects on flow boiling instabilities in expanding microgap channel3.4Conclusions     ReferencesChapter 4: Flow Boiling Heat Transfer, Pressure Drop and Instabilities in Straight and Expanding (Sloping Fin) Microchannels - A Comparative Study4.1Experimental Setup and Procedure4.2Flow boiling regimes and bubble dynamics in straight and sloping fin microchannels4.3Comparison of boiling curves between straight and sloping fin microchannels4.4Comparison of heat transfer coefficients between straight and sloping fin microchannels4.5Comparison of pressure drops between straight and sloping fin microchannels4.6Comparison of instabilities between straight and sloping fin microchannels4.7Conclusions     ReferencesChapter 5: Flow Boiling Performance in Scaled Up Expanding Channel Geometries: Stepped Fin Minichannels5.1 Experimental Setup and Procedure5.2 Comparison of boiling curves between straight and stepped fin minichannels5.3 Comparison of heat transfer coefficients between straight and stepped fin minichannels5.4 Comparison of pressure drops between straight and stepped fin minichannels5.5 Comparison of wall temperature uniformity between straight and stepped fin minichannels5.6 Conclusions     ReferencesChapter 6: ClosureAppendix A: Uncertainty AnalysisAppendix B: Data Reduction