The gas-absorption/chemical-reaction (GACR) method used in chemical engineering to quantify gas-liquid interfacial area in reactor systems is adapted for the first time to measure the effective air-water interfacial area of natural porous media. Experiments were conducted with the GACR method, and two standard methods (X-ray microtomographic imaging and interfacial partitioning tracer tests) for comparison, using model glass beads and a natural sand. The results of a series of experiments conducted under identical conditions demonstrated that the GACR method exhibited excellent repeatability for measurement of interfacial area (A(ia)). Coefficients of variation for A(ia) were 3.5% for the glass beads and 11% for the sand. Extrapolated maximum interfacial areas (A(m)) obtained with the GACR method were statistically identical to independent measures of the specific solid surface areas of the media. For example, the A(m) for the glass beads is 29 (1) cm(-1), compared to 32 (3), 30 (2), and 31 (2) cm(-1) determined from geometric calculation, N2/BET measurement, and microtomographic measurement, respectively. This indicates that the method produced accurate measures of interfacial area. Interfacial areas determined with the GACR method were similar to those obtained with the standard methods. For example, A(ia)s of 47 and 44 cm(-1) were measured with the GACR and XMT methods, respectively, for the sand at a water saturation of 0.57. The results of the study indicate that the GACR method is a viable alternative for measuring air-water interfacial areas. The method is relatively quick, inexpensive, and requires no specialized instrumentation compared to the standard methods.

Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The expansion of the global fuels industry has caused an increase in the quantity of hydrocarbons produced as a by-product of refinery gas-to-liquid processes. Conversion of hydrocarbons to higher value products is possible using bioprocesses, which are sustainable and environmentally benign. Due to the deficiency of oxygen in the alkane molecule, the supply of sufficient oxygen through aeration is a major obstacle for the optimization of hydrocarbon bioprocesses. While the oxygen solubility is increased in the presence of hydrocarbons, under certain process conditions, the enhanced solubility is outweighed by an increase in viscosity, causing a depression in overall volumetric oxygen transfer coefficient (KLa). The rate at which oxygen is transferred is defined in terms of a concentration driving force (oxygen solubility) and the overall volumetric oxygen transfer coefficient (KLa). The KLa term comprises an oxygen transfer coefficient (KL) and the gas-liquid interfacial area (a), which are dependent on the uid properties and system hydrodynamics. This behaviour is not well understood for hydrocarbon bioprocesses and in a bubble column reactor (BCR). To provide an understanding of oxygen transfer behaviour, a model hydrocarbon bioprocess was developed using a BCR with a porous sparger. To evaluate the interfacial area, the Sauter mean bubble diameter (D32) was measured using an image analysis algorithm and gas holdup (ϵG) was measured by the change in liquid height in the column. Together the D32 and ϵG were used in the calculation of interfacial area in the column. The KLa was evaluated with incorporation of the probe response lag, allowing more accurate representation of the KLa behaviour. The probe response lag was measured at all experimental conditions to ensure accuracy and reliability of data. The model hydrocarbon bioprocess employed C14-20 alkane-aqueous dispersions (2.5 - 20 vol% hydrocarbon) with suspended solids (0.5 - 6 g/l) at discrete super ficial gas velocity (uG) (1 - 3 cm/s). For systems with inert solids (corn our, dp = 13.36 m), the interfacial area and KLa were measured and the behaviour of KLa was described by separation of the in uences of interfacial area and oxygen transfer coefficient (KL). To further the understanding of oxygen transfer behaviour, non-viable yeast cells (dp = 5.059 m) were used as the dispersed solid phase and interfacial area behaviour was determined. This interfacial area behaviour was compared with the behaviour of systems with inert solids to understand the differences with change in solids type. In systems using inert solids, a linear relationship was found between G and uG. An empirical correlation fo rthe prediction of this behaviour showed an accuracy of 83.34% across the experimental range. The interfacial area showed a similar relationship with uG and the empirical correlation provided an accuracy of 78.8% for prediction across the experimental range. In inert solids dispersions, the KLa increased with uG as the result of an increase in interfacial area as well as increases in KL. An increase in solids loading indicated an initial increase in KLa, due to the in uence of liquid-film penetration on KL, followed by a decrease in KL at solids loading greater than 2.5 g/l, due to diffusion blocking effects. In systems with yeast dispersions, the presence of surfactant molecules in the media inhibited coalescence up to a yeast loading of about 3.5 g/l, and resulted in a decrease in D32. Above this yeast loading, the fine yeast particles increased the apparent viscosity of the dispersion sufficiently to overcome the in uence of surfactant and increase the D32. The behaviour of G in yeast dispersions was similar to that found with inert solids and demonstrated a linear increase with uG. However, in yeast dispersions, the interaction between alkane concentration and yeast loading caused a slight increase in dispersion viscosity and therefore G. An empirical correlation to predict G behaviour with increased uG was developed with an accuracy of 72.55% for the experimental range considered. Comparison of yeast and inert solids dispersions indicated a 37.5% lower G in yeast dispersions compared to inert solids as a result of the apparent viscosity introduced by finer solid particles. This G and D32 data resulted in a linear increase in interfacial area with uG with no significant in uence of alkane concentration and yeast loading. This interfacial area was on average 6.7% lower than interfacial area found in inert solid dispersions as a likely consequence of the apparent viscosity with finer particles. This study provides a fundamental understanding of the parameters which underpin oxygen transfer in a model hydrocarbon bioprocess BCR under discrete hydrodynamic conditions. This fundamental understanding provides a basis for further investigation of hydrocarbon bioprocesses and the prediction of KLa behaviour in these systems. / AFRIKAANSE OPSOMMING: Die uitbreiding van die internasionale brandstofbedryf het 'n toename veroorsaak in die hoeveelheid koolwaterstowwe geproduseer as 'n deur-produk van raffinadery gas-tot-vloeistof prosesse. Omskakeling van koolwaterstowwe na hoër waarde produkte is moontlik met behulp van bioprosesse, wat volhoubaar en omgewingsvriendelik is. As gevolg van die tekort aan suurstof in die alkaan molekule, is die verskaffing van voldoende suurstof deur deurlugting 'n groot uitdaging vir die optimalisering van koolwaterstof bioprosesse. Terwyl die suurstof oplosbaarheid verhoog in die teenwoordigheid van koolwaterstowwe, onder sekere proses voorwaardes is die verhoogde oplosbaarheid oortref deur 'n toename in viskositeit, wat 'n depressive veroorsaak in die algehele volumetriese suurstofoordragkoëffisiënt (KLa). Die suurstof oordrag tempo word gedefinieer in terme van 'n konsentrasie dryfkrag (suurstof oplosbaarheid) en KLa. Die KLa term behels 'n suurstofoordragkoëffisiënt (KL) en die gas-vloeistof oppervlakarea (a), wat afhanklik is van die vloeistof eienskappe en stelsel hidrodinamika. Hierdie gedrag is nie goed verstaan vir koolwaterstof bioprosesse nie, asook in kolom reaktors (BCR). Om 'n begrip van suurstof oordrag gedrag te voorsien, is 'n model koolwaterstof bioproses ontwikkel met 'n BCR met 'n poreuse besproeier. Om die oppervlakarea te evalueer, is die gemiddelde Sauter deursnit (D32) gemeet deur 'n foto-analise algoritme en gas vasvanging ( G) is gemeet deur die verandering in vloeibare hoogte in die kolom. Saam is die D32 en G gebruik in die berekening van die oppervlakarea in die kolom. Die KLa is geëvalueer met insluiting van die meter se reaksie sloering, om n meer akkurate voorstelling van die KLa gedrag te bereken. Die meter reaksie sloering was gemeet op alle eksperimentele toestande om die akkuraatheid en betroubaarheid van data te verseker. Die model koolwaterstof bioproses gebruik n-C14-20 alkaan-water dispersies (2.5 - 20 vol% koolwaterstof) solide partikels (0.5 - 6 g/l) op diskrete oppervlakkige gas snelhede (1 - 3 cm/s). Vir stelsels met inerte solides (koring meel, dp = 13.36 m), is die oppervlakarea en KLa gemeet en die gedrag van KLa beskryf deur skeiding van die invloede van oppervlakarea en KL. Om die begrip van suurstof oordrag se gedrag te bevorder, is nie-lewensvatbare gisselle (dp = 5.059 m) gebruik as die verspreide solide fase en oppervlakarea is bepaal. Hierdie oppervlakarea gedrag is vergelyk met die van stelsels met inerte solides om die verskille met verandering in solide tipes te verstaan. In stelsels met inerte solides, is 'n line^ere verwantskap gevind tussen G en uG. 'n Empiriese korrelasie vir die voorspelling van hierdie gedrag is opgestel met 'n akkuraatheid van 83.34% in die eksperimentele reeks. Die oppervlakarea het 'n soortgelyke verhouding met uG en die empiriese korrelasie verskaf 'n akkuraatheid van 78,8% vir die voorspelling van oppervlakarea oor die eksperimentele reeks. In inerte solide dispersies, het die KLa toegeneem met uG as die gevolg van 'n toename in grens oppervlak asook stygings in KL. 'n Toename in solides belading het n aanvanklike styging in KLa aangedui, as gevolg van die invloed van die vloeistof-film penetrasie op KL, gevolg deur 'n afname in KL op vastestowwe ladings groter as 2.5 g/l, te danke aan diffusie blokkeer effekte. In stelsels met gis dispersies, het die teenwoordigheid van benattings molekules in die media samesmelting geïnhibeer tot 'n gis lading van ongeveer 3.5 g/l, en het gelei tot 'n afname in D32. Bo hierdie gis lading, het die fyn gis partikels die skynbare viskositeit van die verspreiding verhoog genoegsaam om die invloed van benattings molekules te oorkom en die D32 te verhoog. Die gedrag van G in gis dispersies was soortgelyk aan die van inerte solides en dui op 'n lineêre toename met uG. Maar in gis dispersies, het die interaksie tussen alkaan konsentrasie en gis lading 'n effense toename veroorsaak in die verstrooiing viskositeit en dus in G. 'n Empiriese korrelasie is ontwikkel om G gedrag te voorspel en het 'n akkuraatheid van 72,55% vir die eksperimentele verskeidenheid beskou. Vergelyking van gis en inerte patrikel dispersies wys 'n 37.5% laer G in gis dispersies in vergelyking met inerte vaste stowwe as 'n gevolg van die skynbare viskositeit bekendgestel deur fyner vastestowwe partikels. Hierdie G en D32 data het gelei tot 'n linere toename in grens oppervlak met uG met geen beduidende invloed van alkaan konsentrasie en gis lading nie. Die oppervlakarea was gemiddeld 6.7% laer as oppervlakarea gevind in inerte partikel dispersies as 'n waarskynlike gevolg van die skynbare viskositeit met fyner partikels. Hierdie studie bied 'n fundamentele begrip van die veranderlikes wat die suurstof oordrag definieer in 'n model koolwaterstof bioproses BCR onder diskrete hidrodinamiese voorwaardes. Hierdie fundamentele begrip bied n basis vir verdere ondersoek van koolwaterstof bioprosesse en en die voorspelling van KLa gedrag in hierdie stelsels.

For the investigation of stratified two-phase flow, two horizontal channels with rectangular cross-section were built at Forschungszentrum Dresden-Rossendorf (FZD). The channels allow the investigation of air/water co-current flows, especially the slug behaviour, at atmospheric pressure and room temperature. The test-sections are made of acrylic glass, so that optical techniques, like high-speed video observation or particle image velocimetry (PIV), can be applied for measurements. The rectangular cross-section was chosen to provide better observation possibilities. Moreover, dynamic pressure measurements were performed and synchronised with the high-speed camera system. CFD post-test simulations of stratified flows were performed using the code ANSYS CFX. The Euler-Euler two fluid model with the free surface option was applied on grids of minimum 4∙105 control volumes. The turbulence was modelled separately for each phase using the k-ω based shear stress transport (SST) turbulence model. The results compare well in terms of slug formation, velocity, and breaking. The qualitative agreement between calculation and experiment is encouraging and shows that CFD can be a useful tool in studying horizontal two-phase flow. Furthermore, CFD pre-test calculations were done to show the possibility of slug flow generation in a real geometry and at relevant parameters for nuclear reactor safety. The simulation was performed on a flat model representing the hot-leg of the German Konvoi-reactor, with water and saturated steam at 50 bar and 263.9°C. The results of the CFD-calculation show wave generation in the horizontal part of the hot-leg which grow to slugs in the region of the bend.

For the investigation of stratified two-phase flow, two horizontal channels with rectangular cross-section were built at Forschungszentrum Dresden-Rossendorf (FZD). The channels allow the investigation of air/water co-current flows, especially the slug behaviour, at atmospheric pressure and room temperature. The test-sections are made of acrylic glass, so that optical techniques, like high-speed video observation or particle image velocimetry (PIV), can be applied for measurements. The rectangular cross-section was chosen to provide better observation possibilities. Moreover, dynamic pressure measurements were performed and synchronised with the high-speed camera system. CFD post-test simulations of stratified flows were performed using the code ANSYS CFX. The Euler-Euler two fluid model with the free surface option was applied on grids of minimum 4∙105 control volumes. The turbulence was modelled separately for each phase using the k-ω based shear stress transport (SST) turbulence model. The results compare well in terms of slug formation, velocity, and breaking. The qualitative agreement between calculation and experiment is encouraging and shows that CFD can be a useful tool in studying horizontal two-phase flow. Furthermore, CFD pre-test calculations were done to show the possibility of slug flow generation in a real geometry and at relevant parameters for nuclear reactor safety. The simulation was performed on a flat model representing the hot-leg of the German Konvoi-reactor, with water and saturated steam at 50 bar and 263.9°C. The results of the CFD-calculation show wave generation in the horizontal part of the hot-leg which grow to slugs in the region of the bend.

O processo de absorção do CO2 em soluções aquosas de alcanolaminas foi estudado em uma coluna de parede molhada empregando-se uma tela metálica, de 28 mesh, como promotor de película e operando em contracorrente. As alcanolaminas testadas nos diferentes experimentos foram: monoetanolamina (MEA), 2-amino-2-metil-1-propanol (AMP) e piperazina (PZ). Os experimentos de absorção foram realizados nas soluções aquosas individuais da MEA e AMP; e, nas misturas MEA:AMP e AMP:PZ; visando avaliar a velocidade de absorção do CO2 em diferentes vazões do líquido, a saber: 3.10-7, 6.10-7 e 10.10-7 m3/s. O presente sistema de absorção foi caracterizado através da determinação dos principais parâmetros de transferência de massa: área interfacial efetiva, coeficiente de transferência individual da fase gasosa e o coeficiente volumétrico global médio de transferência de massa. Determinou-se a área interfacial efetiva da coluna, por meio da absorção do CO2 diluído em ar em uma solução aquosa de NaOH, para as diferentes vazões de líquido, sendo os resultados obtidos igual a 106, 126 e 144 m2/m3, respectivamente. O coeficiente volumétrico de transferência de massa da fase gasosa foi determinado por meio da absorção de SO2 diluído em ar em uma solução aquosa de NaOH. Os resultados experimentais mostram que o coeficiente volumétrico individual de transferência de massa e a área interfacial são função da vazão do líquido. As velocidades de absorção do CO2 diluído em ar, em soluções de aminas e suas misturas foram determinadas experimentalmente para diferentes vazões de líquido, sendo os resultados expressos na forma de coeficientes globais de transferência de massa e parâmetros cinético-difusivos da fase líquida. As velocidades de absorção em MEA são bem superiores aos de AMP e NaOH. No caso das misturas foram obtidas velocidades superiores em comparação às das aminas individuais. A velocidade de absorção em AMP é fortemente incrementada na presença de PZ, mesmo em baixa concentração. / The CO2 absorption process in alkanolamine aqueous solutions was studied in a wetted wall column employing a film promotor of thin stainless steel woven wire, 28 mesh, which was operated in countercurrent. The tested alkanolamines were monoethanolamine (MEA), 2-amino-2-methyl-1-propanol (AMP) and piperazine (PZ). The absorption experiments were performed in individual aqueous solutions of MEA and AMP and the mixtures MEA:AMP and AMP:PZ, with the aim of evaluating the CO2 absorption rate in different liquid flow rates, namely: 3.10-7, 6.10-7 e 10.10-7 m3/s. This absorption system was characterized through determining of the main parameters of mass transfer: effective interfacial area, individual mass transfer coefficient of the gas phase and the average overall mass transfer volumetric coefficient. The effective interfacial area was determined by the absorption of CO2 diluted in air into an aqueous solution of NaOH for the different liquid flow rates, and the results obtained are 106, 126 and 144 m2/m3, respectively. The mass transfer volumetric coefficient of the gas phase was determined by chemical method of the absorption of SO2 diluted in air into an aqueous solution of NaOH. The experimental results show that the individual mass transfer coefficient and interfacial area are a function of liquid flow rate. On the other hand, the results of the performance of CO2 absorption into amine aqueous solutions were expressed in function of the average overall mass transfer volumetric coefficient and liquid phase diffusive kinetic parameters, which were measured experimentally for different liquid flow rates. The absorption rate in MEA are higher in comparison with AMP and NaOH. In the case of the blended, the absorption rate in AMP is enhanced by piperazine, even in low concentration.

Nach einer kurzen technischen Beschreibung der Mehrzweck-Thermohydraulikversuchsanlage TOPFLOW und der verwendeten Messtechnik werden die theoretischen Grundlagen zur Modellierung der Kondensation von Dampf in einer Wasserströmung erläutert. Dabei gehen die Autoren besonders auf die Auswahl geeigneter Modelle zur Beschreibung des Wärmeübergangs und der Zwischenphasengrenzfläche im Druckbereich zwischen 10 und 65 bar detailliert ein. Außerdem werden verschiedene Drift-Flux-Modelle auf ihre Tauglichkeit anhand von experimentellen Daten geprüft. Da Veränderungen thermodynamischer und strömungstechnischer Parameter hauptsächlich in axialer Richtung stattfinden, wurden diese Modelle in einen eindimensionalen Code eingebettet, mit dem der Strömungsverlauf entlang einer vertikalen Rohrleitung mit einer Länge von 8 m und einem Nenndurchmesser von 200 mm berechnet werden kann. Anschließend werden Aufbau und Funktion dieses Programms vorgestellt. Nachfolgend vergleichen die Autoren experimentelle und berechnete Strömungsverläufe bei der Kondensation von Dampf sowohl in einer unterkühlten Wasserströmung als auch nahe der Siedetemperatur. Dabei wird der Einfluss wichtiger Randbedingungen, wie z.B. Druck oder Primärblasengröße, auf die Kondensationsintensität analysiert. Eine Einschätzung der Fehlerbanden für die experimentellen Daten, die verwendeten Gittersensoren und die numerische Simulation schließen den Bericht ab.

Interfacial partitioning tracer tests (IPTT) are one method available for measuring air-water interfacial area (A(ia)).This study used the standard approach comprising tracer injection under steady unsaturated-flow conditions with a uniform water-saturation distribution within the column. Sodium dodecylbezene sulfonate (SDBS) and pentafluorobenzoic acid (PFBA) were used as the partitioning and nonreactive tracers, respectively. Three types of porous media were used for the study: a sandy soil, a well-sorted sand, and glass beads. Initial water saturations, S(w), were approximately 80%, 80%, and 26 % for the soil, sand, and glass beads, respectively. Water saturation was monitored gravimetrically during the experiments. The maximum interfacial areas (A(ia)/(1-S(w))) calculated from the results of the experiments are compared among the three porous media used in this work, and compared to previous air-water interfacial area studies.

O processo de absorção do CO2 em soluções aquosas de alcanolaminas foi estudado em uma coluna de parede molhada empregando-se uma tela metálica, de 28 mesh, como promotor de película e operando em contracorrente. As alcanolaminas testadas nos diferentes experimentos foram: monoetanolamina (MEA), 2-amino-2-metil-1-propanol (AMP) e piperazina (PZ). Os experimentos de absorção foram realizados nas soluções aquosas individuais da MEA e AMP; e, nas misturas MEA:AMP e AMP:PZ; visando avaliar a velocidade de absorção do CO2 em diferentes vazões do líquido, a saber: 3.10-7, 6.10-7 e 10.10-7 m3/s. O presente sistema de absorção foi caracterizado através da determinação dos principais parâmetros de transferência de massa: área interfacial efetiva, coeficiente de transferência individual da fase gasosa e o coeficiente volumétrico global médio de transferência de massa. Determinou-se a área interfacial efetiva da coluna, por meio da absorção do CO2 diluído em ar em uma solução aquosa de NaOH, para as diferentes vazões de líquido, sendo os resultados obtidos igual a 106, 126 e 144 m2/m3, respectivamente. O coeficiente volumétrico de transferência de massa da fase gasosa foi determinado por meio da absorção de SO2 diluído em ar em uma solução aquosa de NaOH. Os resultados experimentais mostram que o coeficiente volumétrico individual de transferência de massa e a área interfacial são função da vazão do líquido. As velocidades de absorção do CO2 diluído em ar, em soluções de aminas e suas misturas foram determinadas experimentalmente para diferentes vazões de líquido, sendo os resultados expressos na forma de coeficientes globais de transferência de massa e parâmetros cinético-difusivos da fase líquida. As velocidades de absorção em MEA são bem superiores aos de AMP e NaOH. No caso das misturas foram obtidas velocidades superiores em comparação às das aminas individuais. A velocidade de absorção em AMP é fortemente incrementada na presença de PZ, mesmo em baixa concentração. / The CO2 absorption process in alkanolamine aqueous solutions was studied in a wetted wall column employing a film promotor of thin stainless steel woven wire, 28 mesh, which was operated in countercurrent. The tested alkanolamines were monoethanolamine (MEA), 2-amino-2-methyl-1-propanol (AMP) and piperazine (PZ). The absorption experiments were performed in individual aqueous solutions of MEA and AMP and the mixtures MEA:AMP and AMP:PZ, with the aim of evaluating the CO2 absorption rate in different liquid flow rates, namely: 3.10-7, 6.10-7 e 10.10-7 m3/s. This absorption system was characterized through determining of the main parameters of mass transfer: effective interfacial area, individual mass transfer coefficient of the gas phase and the average overall mass transfer volumetric coefficient. The effective interfacial area was determined by the absorption of CO2 diluted in air into an aqueous solution of NaOH for the different liquid flow rates, and the results obtained are 106, 126 and 144 m2/m3, respectively. The mass transfer volumetric coefficient of the gas phase was determined by chemical method of the absorption of SO2 diluted in air into an aqueous solution of NaOH. The experimental results show that the individual mass transfer coefficient and interfacial area are a function of liquid flow rate. On the other hand, the results of the performance of CO2 absorption into amine aqueous solutions were expressed in function of the average overall mass transfer volumetric coefficient and liquid phase diffusive kinetic parameters, which were measured experimentally for different liquid flow rates. The absorption rate in MEA are higher in comparison with AMP and NaOH. In the case of the blended, the absorption rate in AMP is enhanced by piperazine, even in low concentration.

Nach einer kurzen technischen Beschreibung der Mehrzweck-Thermohydraulikversuchsanlage TOPFLOW und der verwendeten Messtechnik werden die theoretischen Grundlagen zur Modellierung der Kondensation von Dampf in einer Wasserströmung erläutert. Dabei gehen die Autoren besonders auf die Auswahl geeigneter Modelle zur Beschreibung des Wärmeübergangs und der Zwischenphasengrenzfläche im Druckbereich zwischen 10 und 65 bar detailliert ein. Außerdem werden verschiedene Drift-Flux-Modelle auf ihre Tauglichkeit anhand von experimentellen Daten geprüft. Da Veränderungen thermodynamischer und strömungstechnischer Parameter hauptsächlich in axialer Richtung stattfinden, wurden diese Modelle in einen eindimensionalen Code eingebettet, mit dem der Strömungsverlauf entlang einer vertikalen Rohrleitung mit einer Länge von 8 m und einem Nenndurchmesser von 200 mm berechnet werden kann. Anschließend werden Aufbau und Funktion dieses Programms vorgestellt. Nachfolgend vergleichen die Autoren experimentelle und berechnete Strömungsverläufe bei der Kondensation von Dampf sowohl in einer unterkühlten Wasserströmung als auch nahe der Siedetemperatur. Dabei wird der Einfluss wichtiger Randbedingungen, wie z.B. Druck oder Primärblasengröße, auf die Kondensationsintensität analysiert. Eine Einschätzung der Fehlerbanden für die experimentellen Daten, die verwendeten Gittersensoren und die numerische Simulation schließen den Bericht ab.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18272号 / 工博第3864号 / 新制||工||1593(附属図書館) / 31130 / 京都大学大学院工学研究科原子核工学専攻 / (主査)教授 功刀 資彰, 教授 中部 主敬, 准教授 横峯 健彦 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM