No description available.

Geometrical parameterisation has an important role in the aircraft design process due to its impact on the computational efficiency and accuracy in evaluating different configurations. In the early design stages, an aircraft geometrical model is normally described parametrically with a small number of design parameters which allows fast computation. However, this provides only a course approximation which is generally limited to conventional configurations, where the models have already been validated. An efficient parameterisation method is therefore required to allow rapid synthesis and analysis of novel configurations. Within this context, the main objectives of this research are: 1) Develop an economical geometrical parameterisation method which captures sufficient detail suitable for aerodynamic analysis and optimisation in early design stage, and2) Close the gap between conceptual and preliminary design stages by bringing more detailed information earlier in the design process. Research efforts were initially focused on the parameterisation of two-dimensional curves by evaluating five widely-cited methods for airfoil against five desirable properties. Several metrics have been proposed to measure these properties, based on airfoil fitting tests. The comparison suggested that the Class-Shape Functions Transformation (CST) method is most suitable and therefore was chosen as the two-dimensional curve generation method. A set of blending functions have been introduced and combined with the two-dimensional curves to generate a three-dimensional surface. These surfaces form wing or body sections which are assembled together through a proposed joining algorithm. An object-oriented structure for aircraft components has also been proposed. This allows modelling of the main aircraft surfaces which contain sufficient level of accuracy while utilising a parsimonious number of intuitive design parameters.

Geometrical parameterisation has an important role in the aircraft design process due to its impact on the computational efficiency and accuracy in evaluating different configurations. In the early design stages, an aircraft geometrical model is normally described parametrically with a small number of design parameters which allows fast computation. However, this provides only a course approximation which is generally limited to conventional configurations, where the models have already been validated. An efficient parameterisation method is therefore required to allow rapid synthesis and analysis of novel configurations. Within this context, the main objectives of this research are: 1) Develop an economical geometrical parameterisation method which captures sufficient detail suitable for aerodynamic analysis and optimisation in early design stage, and2) Close the gap between conceptual and preliminary design stages by bringing more detailed information earlier in the design process. Research efforts were initially focused on the parameterisation of two-dimensional curves by evaluating five widely-cited methods for airfoil against five desirable properties. Several metrics have been proposed to measure these properties, based on airfoil fitting tests. The comparison suggested that the Class-Shape Functions Transformation (CST) method is most suitable and therefore was chosen as the two-dimensional curve generation method. A set of blending functions have been introduced and combined with the two-dimensional curves to generate a three-dimensional surface. These surfaces form wing or body sections which are assembled together through a proposed joining algorithm. An object-oriented structure for aircraft components has also been proposed. This allows modelling of the main aircraft surfaces which contain sufficient level of accuracy while utilising a parsimonious number of intuitive design parameters ... [cont.].

This thesis deals with the aerodynamic analysis and shape modifications of the ARES aircraft. The analysis focuses on the evaluation lift, drag, and pitching moment coefficient, and further to identify the locations of stripping stream which is characterized by high drag. Before the analysis calibration of the CFD solver is done with the model, which has been measured in the wind tunnel. The aim of calibration is to verify the accuracy and veracity of the methodology used in mesh creation and calculated values. Calculated values are compared with measured data. The shape modifications of the aircraft are focused on conceptual design of the suction inlets for cooling radiators and engine aircraft. Aerodynamic analysis is performed with the modified model in order to determine the variation of lift, drag and pitching moment coefficient from its original configuration.

This thesis deals with determination of effect of wing flexibility on load distribution. FSI analysis using modal superposition was used for determination of effect of wing flexibility. Analysis was verified by analytic calculation. Differences of load distribution, between rigid and flexible wing, was determined for the selected flight regimes. Change of the bending moment was up to 3,9 %. Thesis shows importance of including effect of wing flexibility for sailplane design.

Thesis deals with design of a single-engine aircraft. The purpose of this aircraft design is to carry up nine passengers. The work outlines technical solution of several structural elements. The design starts with aerodynamic calculations, mass analysis and concludes with calculation of flight performance and development cost estimation.

No description available.

This thesis is based around examination of three mainstream inhaled drugs Formoterol, Budesonide and Beclomethasone for treatment of asthma and COPD. The areas investigated are these which have been raised in reports and studies, where there are concern, for drug use and assessment of their use. In reporting this work the literature study sets out a brief summary of the background and anatomy and physiology of the respiratory system and then discuses the mechanism of drug deposition in the lung, as well as the methods of studying deposition and pulmonary delivery devices. This section includes the basis of asthma and COPD and its treatment. In addition, a short section is presented on the role of the pharmacist in improving asthma and COPD patient's care. Therefore the thesis is divided into 3 parts based around formoterol, budesonide and beclomethasone. In the first case the research determines the in-vitro performance of formoterol and budesonide in combination therapy. In the initial stage a new rapid, robust and sensitive HPLC method was developed and validated for the simultaneous assay of formoterol and the two epimers of budesonide which are pharmacologically active. In the second section, the purpose was to evaluate the aerodynamic characteristics for a combination of formoterol and the two epimers of budesonide at inhalation flow rates of 28.3 and 60 L/min. The aerodynamic characteristics of the emitted dose were measured by an Anderson cascade impactor (ACI) and the next generation cascade impactor (NGI). In all aerodynamic characterisations, the differences between flow rates 28.3 and 60 were statistically significant in formoterol, budesonide R and budesonide S, while the differences between ACI and NGI at 60 were not statistically significant. Spacers are commonly used especially for paediatric and elderly patients. However, there is considerable discussion about their use and operation. In addition, the introduction of the HFAs propellants has led to many changes in the drug formulation characteristics. The purpose of the last section is to examine t h e performance of different types of spacers with different beclomethasone pMDIs. Also, it was to examine the hypothesis of whether the result of a specific spacer with a given drug/ brand name can be extrapolated to other pMDIs or brand names for the same drug. The results show that there are different effects on aerodynamic characterisation and there are significant differences in the amount of drug available for inhalation when different spacers are used as inhalation aids. Thus, the study shows that the result from experiments with a combination of a spacer and a device cannot be extrapolated to other combination.

Αντικείμενο της εργασίας είναι η αεροδυναμική και αεροακουστική ανάλυση στροφείων ανεμοκινητήρων οριζοντίου άξονα (α-ο-α). Ο υπολογισμός του πεδίου ροής και των αεροδυναμικών συντελεστών του στροφείου ενός ανεμοκινητήρα επιτυγχάνεται κατά δύο τρόπους, με σκοπό την άμεση σύγκριση των αποτελεσμάτων με κριτήρια αφενός την ακρίβεια και αφετέρου την ευκολία ή πρακτικότητα που προσδιορίζεται κύρια σε όρους χρόνου υπολογισμού και διαθεσιμότητας υπολογιστικών πόρων. Οι δύο επιλεγμένοι τρόποι που διαφοροποιούνται στην φυσικο-μαθηματική μοντελοποίηση του προβλήματος ροής γύρω από το στροφείο του ανεμοκινητήρα, αποτελούν δύο δοκιμασμένες μεθοδολογίες ή τεχνικές ανάλυσης και σχεδιασμού περιστρεφόμενων στροφείων, τα οποία μπορούν να λειτουργούν ως κινητήριες μηχανές ή ως εργομηχανές, είναι η μέθοδος των επιφανειακών στοιχείων και η αριθμητική επίλυση των εξισώσεων Navier-Stokes. Για την αξιολόγηση των υπολογιστικών αποτελεσμάτων επιλέχθηκε ως στροφείο αναφοράς, ο πειραματικός ανεμοκινητήρας NREL phase II. Ο αλγόριθμος των επιφανειακών στοιχείων συμπλέχτηκε με ολοκληρωτικά σχήματα πρόλεξης και υπολογισμού του οριακού στρώματος με σκοπό να συμπεριληφθούν τα φαινόμενα συνεκτικότητας της ροής. Πραγματοποιήθηκε παραμετρική ανάλυση του δρομέα του ανεμοκινητήρα για διαφορετικές συνθήκες λειτουργίας του. Η σύγκριση των αποτελεσμάτων των συντελεστών πίεσης των περιστρεφόμενων πτερυγίων για τέσσερις θέσεις κατά το εκπέτασμα του πτερυγίου με τα πειραματικά δεδομένα δείχνει ικανοποιητική συμφωνία. Για την ανάλυση του πεδίου ροής που παράγεται γύρω από περιστρεφόμενους δρομείς α-ο-α χρησιμοποιήθηκε η μέθοδος της υπολογιστικής ρευστοδυναμικής (CFD). Πραγματοποιήθηκαν RANS προσομοιώσεις για διαφορετικές συνθήκες λειτουργίας του ανεμοκινητήρα και για τέσσερα διαφορετικά μοντέλα τύρβης. Το k-ω SST μοντέλο τύρβης έχει τις μικρότερες αποκλίσεις με τα πειραματικά αποτελέσματα. Η αεροακουστική ανάλυση του στροφείου ενός ανεμοκινητήρα επιτυγχάνεται με την επίλυση της ακουστικής εξίσωσης Ffowcs-Williams Hawkings, μέσω ενός υπολογιστικού κώδικα που αναπτύχθηκε γι’ αυτό το σκοπό. Από τα αποτελέσματα των προσομοιώσεων, φάνηκε στα ροδογράμματα κατευθυντικότητας του ήχου, τα επίπεδα της ακουστικής πίεσης να είναι υψηλότερα για θέσεις παρατηρητή ανάντη και κατάντη του ανεμοκινητήρα. / The aim of this study is to represent the aerodynamic and aeroacoustic analysis of horizontal axis wind turbine (ΗAWT) rotors. The calculation of the flow field and the aerodynamic coefficients over the wind turbine rotor are performed using two methodologies, the panel method and the numerical solution of Navier-Stokes equations. These two methodologies are differentiated in the mathematical modeling approach of the flow around the rotor and are utilized in the design and manufacturing phases of horizontal axis wind turbine rotors. Moreover, the results of these two methodologies are compared in terms of the accuracy and the computational time required. For the evaluation of the computational results the experimental wind turbine NREL phase II is chosen as the reference rotor. An invicid/viscous interaction algorithm is developed using integral boundary layer equations coupled with the low order panel method solution in order to account the viscous effects. A parametric analysis of the wind turbine rotor is conducted for different operating conditions. The comparison of the results of the pressure coefficients of the rotating blades for four spanwise positions along the blade with the experimental data shows satisfactory agreement. The analysis of the near and far flow field of HAWT is obtained via CFD by RANS simulations of four different turbulence models (Spalart-Allmaras, k-ε, k-ε RNG and k-ω SST). From the conducted study, it is confirmed the ability of analysis of a HAWT rotor flow field with the RANS equations and the good agreement of the computations with experimental data, when the k-ω SST turbulence model is used. The aeroacoustic analysis of the HAWT is based on the solution of the Ffowcs Williams-Hawkings (FW-H) equation via a computer code developed for this purpose. The radiation patterns of the calculated aeroacoustic noise show that high level amplitudes are calculated for upwind and downwind positions.

This thesis is based around examination of three mainstream inhaled drugs Formoterol, Budesonide and Beclomethasone for treatment of asthma and COPD. The areas investigated are these which have been raised in reports and studies, where there are concern, for drug use and assessment of their use. In reporting this work the literature study sets out a brief summary of the background and anatomy and physiology of the respiratory system and then discuses the mechanism of drug deposition in the lung, as well as the methods of studying deposition and pulmonary delivery devices. This section includes the basis of asthma and COPD and its treatment. In addition, a short section is presented on the role of the pharmacist in improving asthma and COPD patient¿s care. Therefore the thesis is divided into 3 parts based around formoterol, budesonide and beclomethasone. In the first case the research determines the in-vitro performance of formoterol and budesonide in combination therapy. In the initial stage a new rapid, robust and sensitive HPLC method was developed and validated for the simultaneous assay of formoterol and the two epimers of budesonide which are pharmacologically active. In the second section, the purpose was to evaluate the aerodynamic characteristics for a combination of formoterol and the two epimers of budesonide at inhalation flow rates of 28.3 and 60 L/min. The aerodynamic characteristics of the emitted dose were measured by an Anderson cascade impactor (ACI) and the next generation cascade impactor (NGI). In all aerodynamic characterisations, the differences between flow rates 28.3 and 60 were statistically significant in formoterol, budesonide R and budesonide S, while the differences between ACI and NGI at 60 were not statistically significant. Spacers are commonly used especially for paediatric and elderly patients. However, there is considerable discussion about their use and operation. In addition, the introduction of the HFAs propellants has led to many changes in the drug formulation characteristics. The purpose of the last section is to examine t h e performance of different types of spacers with different beclomethasone pMDIs. Also, it was to examine the hypothesis of whether the result of a specific spacer with a given drug/ brand name can be extrapolated to other pMDIs or brand names for the same drug. The results show that there are different effects on aerodynamic characterisation and there are significant differences in the amount of drug available for inhalation when different spacers are used as inhalation aids. Thus, the study shows that the result from experiments with a combination of a spacer and a device cannot be extrapolated to other combination.