title: The effect of inlet conditions on the air side hydraulic resistance and flow maldistribution in industrial air heaters

authors: Hoffmann-Vocke, Jonas

subjects: flow maldistribution

abstract: Experimental system hydraulic resistance measurements on a scale air heater unit have highlighted the excessive hydraulic resistance of typical industry configurations. Both poor header inlet conditions and large header expansion angles are shown to contribute to system hydraulic resistance magnitudes 20–100% higher than suitable benchmark cases. Typical centrifugal fan system efficiencies well under 80% multiply the system resistance effects resulting in larger fan power penalties. Velocity profile measurements taken upstream and downstream of the test heat exchanger under flow maldistribution conditions provide insight into the flow maldistribution spreading caused by the heat exchanger resistance. The anisotropic resistance of the plate fin-and-tube heat exchanger is shown to result in resistance induced flow dispersion being concentrated in the axis parallel to the plate fins.

text: The effect of inlet conditions on the air side hydraulic resistance and flow maldistribution in industrial air heaters Experimental system hydraulic resistance measurements on a scale air heater unit have highlighted the excessive hydraulic resistance of typical industry configurations. Both poor header inlet conditions and large header expansion angles are shown to contribute to system hydraulic resistance magnitudes 20–100% higher than suitable benchmark cases. Typical centrifugal fan system efficiencies well under 80% multiply the system resistance effects resulting in larger fan power penalties. Velocity profile measurements taken upstream and downstream of the test heat exchanger under flow maldistribution conditions provide insight into the flow maldistribution spreading caused by the heat exchanger resistance. The anisotropic resistance of the plate fin-and-tube heat exchanger is shown to result in resistance induced flow dispersion being concentrated in the axis parallel to the plate fins.

year: 2011

title: Syntheses and ligand interconversions of copper(II) derivatives of the metalloligand [Pt₂(µ-S)₂(PPh₃)₄]

authors: Devoy, Sarah M.

abstract: The reactivity of the metalloligand [Pt₂(µ-S)₂(PPh₃)₄] towards a variety of copper(II)–ligand systems has been studied. Reaction of [Pt₂(µ-S)₂(PPh₃)₄] with copper(II) halide complexes [CuCl₂L](L = 2,2 -bipyridine and 1,10-phenanthroline) gave trinuclear dicationic products [Pt₂(µ-S)₂(PPh₃)₄CuL]²⁺, and the 8-hydroxyquinolinate (hq) complex [Cu(hq)₂] gave [Pt₂(µ-S)₂(PPh₃)₄Cu(hq)]⁺, isolated as their BPh₄⁻ or PF₆⁻ salts. Related cationic complexes with other ancillary amine ligands (1,2-diaminoethane, 1,2-diaminopropane, 1,2-diaminocyclohexane) were obtained by reactions of [Pt₂(µ-S)₂(PPh₃)₄] with CuCl2 and the amine. In contrast, reaction of [Pt₂(µ-S)₂(PPh₃)₄] with CuCl₂ and NH₃ in methanol gave the intensely blue methoxy-bridged dicopper complex [{Pt₂(µ-S)₂(PPh₃)₄Cu(OMe)}₂]²⁺, isolated as its hexafluorophosphate salt. Copper β-diketonate complexes reacted with [Pt₂(µ-S)₂(PPh₃)₄] giving [Pt₂(µ-S)₂(PPh₃)₄Cu(β-diketonate)]⁺PF₆⁻ complexes, with the CH₃COCHCOCH₃(acac) and CF₃COCHCO(2-thienyl)(tta) derivatives characterised by X-ray structure determinations. The local Cu(II) environment ranges from distorted square-planar to an intermediate form of square-planar and tetrahedral. The β-diketonate derivatives show varying stability towards methanolysis, giving [{Pt₂(µ-S)₂(PPh₃)₄Cu(OMe)}₂]²⁺.

text: Syntheses and ligand interconversions of copper(II) derivatives of the metalloligand [Pt₂(µ-S)₂(PPh₃)₄] The reactivity of the metalloligand [Pt₂(µ-S)₂(PPh₃)₄] towards a variety of copper(II)–ligand systems has been studied. Reaction of [Pt₂(µ-S)₂(PPh₃)₄] with copper(II) halide complexes [CuCl₂L](L = 2,2 -bipyridine and 1,10-phenanthroline) gave trinuclear dicationic products [Pt₂(µ-S)₂(PPh₃)₄CuL]²⁺, and the 8-hydroxyquinolinate (hq) complex [Cu(hq)₂] gave [Pt₂(µ-S)₂(PPh₃)₄Cu(hq)]⁺, isolated as their BPh₄⁻ or PF₆⁻ salts. Related cationic complexes with other ancillary amine ligands (1,2-diaminoethane, 1,2-diaminopropane, 1,2-diaminocyclohexane) were obtained by reactions of [Pt₂(µ-S)₂(PPh₃)₄] with CuCl2 and the amine. In contrast, reaction of [Pt₂(µ-S)₂(PPh₃)₄] with CuCl₂ and NH₃ in methanol gave the intensely blue methoxy-bridged dicopper complex [{Pt₂(µ-S)₂(PPh₃)₄Cu(OMe)}₂]²⁺, isolated as its hexafluorophosphate salt. Copper β-diketonate complexes reacted with [Pt₂(µ-S)₂(PPh₃)₄] giving [Pt₂(µ-S)₂(PPh₃)₄Cu(β-diketonate)]⁺PF₆⁻ complexes, with the CH₃COCHCOCH₃(acac) and CF₃COCHCO(2-thienyl)(tta) derivatives characterised by X-ray structure determinations. The local Cu(II) environment ranges from distorted square-planar to an intermediate form of square-planar and tetrahedral. The β-diketonate derivatives show varying stability towards methanolysis, giving [{Pt₂(µ-S)₂(PPh₃)₄Cu(OMe)}₂]²⁺.

year: 2005-07-01

title: Tito Waiata-Tito Pūoro: extending the Kīngitanga music tradition.

authors: Rollo, Te Manaaroha Pirihira

subjects: Kīngitanga

abstract: Since 1858, music has always been an integral part of the Kīngitanga movement in New Zealand. As this music tradition evolves with the introduction of new musical idioms, genres and digital technology, so too do the practices of composing new works. 

The objective of this research was to construct a model for combining waiata, taonga pūoro and New Zealand electroacoustic music, in order to create new works that enhance the Kīngitanga music tradition.  Developing a model for composing and integrating these idioms within a Māori context presented problems, as traditional Māori music conflict with contemporary Western forms. 

To generate a framework and practical model for composing hybrid music, an examination of selected New Zealand works was first carried out through: a) the collection of 50 traditional and contemporary waiata relating to the Kīngitanga b) the collection of 10 New Zealand taonga pūoro works and c) a collection of 10 New Zealand electroacoustic music. An analysis of the music and compositional processes of each idiom implementing the ‘de-construct in order to re-construct’ approach to understand how they work musically and compositionally was accomplished. 

To demonstrate the outcome of my models, six original compositions were presented exploring different aspects of musical composition. These models focused on sound architecture and explored a) communicative relationships between composer, performer, and audience b) Holistic Co-hear-ence, implementing the horizontal and vertical layering model, and c) technical approaches using digital technology. To comply with Māori principles of composition and performance, each model and new work demonstrated Kaupapa Māori , Wairua  and Te Mana - Te Ihi - Te Wehi - Te Tapu . 

The findings and original contributions of this research provide a model that combines two musical traditions and three music idioms, and in turn, may guide contemporary composers in creating new works that extend the Kīngitanga music tradition.

text: Tito Waiata-Tito Pūoro: extending the Kīngitanga music tradition. Since 1858, music has always been an integral part of the Kīngitanga movement in New Zealand. As this music tradition evolves with the introduction of new musical idioms, genres and digital technology, so too do the practices of composing new works. 

The objective of this research was to construct a model for combining waiata, taonga pūoro and New Zealand electroacoustic music, in order to create new works that enhance the Kīngitanga music tradition.  Developing a model for composing and integrating these idioms within a Māori context presented problems, as traditional Māori music conflict with contemporary Western forms. 

To generate a framework and practical model for composing hybrid music, an examination of selected New Zealand works was first carried out through: a) the collection of 50 traditional and contemporary waiata relating to the Kīngitanga b) the collection of 10 New Zealand taonga pūoro works and c) a collection of 10 New Zealand electroacoustic music. An analysis of the music and compositional processes of each idiom implementing the ‘de-construct in order to re-construct’ approach to understand how they work musically and compositionally was accomplished. 

To demonstrate the outcome of my models, six original compositions were presented exploring different aspects of musical composition. These models focused on sound architecture and explored a) communicative relationships between composer, performer, and audience b) Holistic Co-hear-ence, implementing the horizontal and vertical layering model, and c) technical approaches using digital technology. To comply with Māori principles of composition and performance, each model and new work demonstrated Kaupapa Māori , Wairua  and Te Mana - Te Ihi - Te Wehi - Te Tapu . 

The findings and original contributions of this research provide a model that combines two musical traditions and three music idioms, and in turn, may guide contemporary composers in creating new works that extend the Kīngitanga music tradition.

year: 2014