代爾夫特理工大學(xué)可具體申請(qǐng)專(zhuān)業(yè)信息列表

1、Vacant PhD topics at Delft University of Technology as of Note that below overview is by no means exhaustive, so in case you wish to pursue a PhD on topics other than given below, please contact Mr Cees Timmers at HYPERLINK mailto: SubjectDesign of Pd-alloys for hydrogen separation membranesResearch

2、erTo be decidedContact TU Delft Assoc. Professor. Dr. A. J. Bttger, Materials Science and Engineering, Delft University of TechnologyShort descriptionThe development of highly selective hydrogen membranes is one of the main technical challenges associated with the production of high-purity hydrogen

3、in membrane reactors. The membranes should withstand the demanding industrial conditions of high temperatures and pressures in multi-component corrosive gaseous environments. Metal-based membranes, in particular, Pd-based membranes are suitable for this purpose. The lifetime of pure Pd membranes in

4、thermal cycles from operational conditions to room temperature is limited. Failure occurs due to deformation and fracture caused by the large specific volume change upon hydride formation. Longer operation lifetime can be achieved through the addition of specific alloying elements that prevent hydri

5、de formation. The nature of the specific alloying elements i.e. their concentration and distribution in the metal lattice influences the hydrogen solubility and the diffusion through these membranes. This implies that knowledge of the structure and the stability of phases formed during hydrogen abso

6、rption/desorption in Pd alloys is crucial for the prediction of properties such as permeation.This research project aims at the design of metal alloys (fcc and bcc) with tailored properties such as a particular critical temperature for hydride formation. The design is based on a thermodynamic model,

7、 developed at the Delft University, that incorporates the interactions of a binary host metal alloy with interstitials (hydrogen). This enables to predict order-disorder transitions, phase stabilities and specific volumes. In this project (i) the model has to be extended to multi-component alloys an

8、d (ii) has to be applied to design new multi-component alloys. To be able to develop new alloys with not yet know properties, i.e. for systems for which no experimental thermodynamic data are available, ab-initio calculations are required. The calculations of the ground state energies will be prefor

9、med using VASP. The results of the ab-initio calculations serve as an input to the extended statistical thermodynamic model that will be used to determine phase boundaries and other properties.SubjectDevelopment of stable Pd-membranes for hydrogen separation from gas mixturesResearcherTo be decidedC

10、ontact TU Delft Assoc. Professor. Dr. A. J. Bttger, Materials Science and Engineering, Delft University of TechnologyShort descriptionHydrogen is widely used in petroleum refining, production of fertilizers, metallurgical processes and as clean fuel. The energy needed to fulfill the current worldwid

11、e H2 production, i.e. 1.7 billion m3/day, is huge and amounts 1000 TW per year. Most of the H2 is produced from steam reforming of methane that is obtained from natural gas and coal gasification. The energy efficiency of CH4 conversion can be improved considerably by using membrane reactors. By remo

12、ving H2 from the reacting gases, during the combined steam reforming and water gas shift reactions, the CH4 conversion increases from 40% in conventional plants to 90% in a membrane reactor. Besides its energy efficiency, the high purity of the H2 manufactured and the lack of green-house gas emissio

13、n by capture of CO2 are big advantages with respect to conventional technologies. The use of membrane reactors is hindered by the limited lifetime of the membrane material, i.e. the mechanical, thermal and chemical stability under process conditions. Stringent requirement for membrane performance, h

14、igh perm-selectivity and stability, restrict the materials choice. Pd-based membranes are currently the most promising. The lifetime is limited by mechanical failure due to phase transformation, temperature-induced grain growth and segregation as well as fouling. Grain growth and segregation can occ

15、ur at operation temperatures of a membrane reactor. The changes in the microstructure and surface characteristics largely reduce the permeability. By careful alloying many of these issues can be solved.This project aims at the development of thin film membranes with a stable microstructure. To this

16、end experimental observations will be used to determine the dominating processes that cause microstructural changes and to describe these processes on the basis of physical - chemical models. The main experimental tools will be X-ray diffraction and mechanical testing. The MSE-lab is equipped with s

17、everal diffractometers, an in-situ tensile test set-up and an in-situ high-temperature chamber are available.SubjectShockwave-induced spraying of reinforced composite coatingsResearcherTo be decidedContact TU Delft Assoc. Professor Dr. A. J. Bttger, Materials Science and Engineering, Delft Universit

18、y of TechnologyShort descriptionShockwave-Induced Spraying process (also indicated by pulsed gas dynamic spraying) is a recently developed solid-state spraying process for deposition of metals, alloys, cermets on virtually any type of substrate at low temperatures. The relatively low temperatures us

19、ed prevent phase transformations of the feedstock powder. The spraying technique shows higher deposition efficiencies and deposition rates than traditional thermal spray processes. Shockwave-induced spraying can produce relative thick layers (from 200 micron up to 5 mm). Contrary to laser cladding o

20、r hot spraying, where the powder is melted, the (pre-heated) powder is fused to the substrate mainly by means of the kinetic energy of the powder jet. This has several potential advantages over laser cladding and conventional hot spraying: no development of brittle intermetallics and the residual st

21、resses in the coatings are negligible. The coatings also have a significantly improve wear resistance.The project aims at exploring new feedstock powders and applications of the shockwave-induced spraying process and investigating the microstructural changes in the material upon deposition. In relat

22、ion to properties._Investigation of the unsteady aerodynamics and fluid-structure interactions of a flapping-wing MAVFlapping wing aerodynamics: CFD simulation (left) and the Delfly MAV (right)Flapping-wing propulsion is an attractive configuration for small observation MAVs, in view of the advantag

23、es for the flight envelope, permitting both efficient and stable hovering and forward flight conditions. The present research aims to support this development by increasing the understanding of the aerodynamics of flapping wings. More in particular, the aerodynamic performance of the “Delfly” is inv

24、estigated, which is a flapping-wing MAV developed as an autonomous camera platform for observation (see .nl). The higher goal objectives of the research are to exploit this better knowledge of the aerodynamic behaviour of the Delfly in improving its design and performance, especially in the next ste

25、p of further miniaturization of the design. In this project the Aerodynamics Group closely cooperates with the development lab of the Delfly. The interest in the research lies in identifying the relevant phenomena that determine the Delflys flight performance, where in particular the following aspec

26、ts are involved: (1) the highly unsteady and complex vertical flow induced by the flapping wings, especially in the clap-and-fling phase, and the role of vortex generation on flight performance; (2) the impact of wing structure and skin foil flexibility in the interaction of the wing with the flow (

27、fluid-structure interaction). These topics will be investigated by a combination of experimental and numerical analysis techniques.Supervisors: Dr.ir. B.W. van Oudheusden, Prof.dr.drs.ir. H. Bijl (Aerodynamics Group) and Ir.ing B. Remes (MAV lab)_Multimodel coupling for fluidstructure interaction No

28、nlinear aeroelastic phenomena occur in aircraft and wind turbine applications. Accurate prediction of these unwanted fluidstructure interactions requires solution of the coupled flow and structure equations. Typically these are solved in a partitioned manner, coupling a separate (NavierStokes) flow

29、and structure solver. In partitioned fluidstructure interaction computations, strongly coupled physical problems may require a subiterating technique, solving the flow and structure equations several times per time step. These subiterations are computationally expensive as they require solving flow

30、and structure multiple times for a single time step. Acceleration of these subiterations can be obtained by using a multilevel approach, resolving a correction term on a coarse level representation for a defect on the fine level. When the coarse level model consists of a coarse computational mesh, t

31、he method resembles a multigridlike technique. In this project the aim is to use a reduced order model as coarse level representation of the fluidstructure interaction problem. The idea is that the reduced order model can accelerate the convergence of the highfidelity model and that the highfidelity

32、 model can be used to improve (e.g. coefficients of) the reduced order model. The challenge is to develop an algorithm that defines the defect and correction terms and the transfer of data between the fine and coarse level models. Possible complications are differences in dimensionality, nonmatching

33、 computational domains, etc._Ground and fuselage engine inlet vortex study for aircraft engine integration Under certain, not very well classified/understood conditions, the flow induced around a stationary or slowly moving (taxiing) aircraft on the ground will separate from the fuselage, roll up in

34、to an axial vortex and cause significant distortion of the flow in the engine intake plane. Just like in the case with the wake of the aileron, the distortion of the flow not only reduces the engine efficiency, it also introduces unsteady loads on the engine parts and thereby reduces the life expect

35、ancy of the engine adding to the operational costs. The passenger discomfort is a secondary disadvantage. Since the trend in modern aero engines is to increase the inlet diameter driven by quieter and more efficient operations, the proximity of the engines to the ground or fuselage is affected. This

36、 may put the engines in a position that may be more susceptible to be in a condition where inlet vortices could occur. Also new configurations like the blended wing-body configuration, where up to now no research about this problem has been done, need to be considered. Other developments in engine t

37、echnology like the unducted fan, in the near future a serious alternative for the turbofan engine in e.g. fuselage mounted engine configurations where no information is available on this subject, need to be considered seriously. The inlet vortex itself is known for more than fifty years and several

38、studies have been conducted to analyze this phenomenon. From simple observational studies to numerical simulations performed in recent years. The analysis of the problem in terms of fluid dynamic characteristics is still rather sparse. A thorough research project should consider the low speed phenom

39、enological aspects of the engine flow. Starting with the concept of a modern high bypass ratio engine (VHBR or UHBR), several configurations should be studied for their tendency to create an inlet vortex in various ambient flow conditions: still air, head wind, tail wind and side wind. This should b

40、e further studied in order to obtain deeper insight into the interaction of the pressure field with the solid boundary in order to obtain configuration independent criteria for the occurrence of vortices upstream of an engine inlet. Also the severity of the negative effects on the engine should be t

41、aken into account. It should follow logically that this is then expanded into propellers and unducted fans. In summary, for the establishment of reliable design rules and design tools a thorough analysis is required. This analysis can only be successfully performed by combination of a numerical and

42、an experimental simulation into a single approach. The numerical approach will need good experiments to provide validation of turbulence modeling and separation locations. The experiments validate parameter space and modifications with great efficiency. They must start with simple preliminary data g

43、athering tests at the TUD and end (with the support of the EU commission) in a large-scale simulation of realistic future configurations in the LLF of the DNW._Error Estimation and Uncertainty quantification for Coupled FluidStructure Simulations The good news is that nowadays we can solve nonlinear

44、 fluidstructure interactions, numerically solving the coupled flow and structure equations. The bad news is that the result of the simulation often does not coincide with observations. This can be due to numerical errors or model errors or uncertainties. In this project an error and uncertainty quan

45、tification technique will be further developed and applied to aeroelastic problems. For the numerical error a posteriori error estimation has been demonstrated as a valuable tool in aerodynamic analysis, delivering reliable estimates of error in integrated quantities that allow an engineer to judge

46、seriously the quality of a simulation. The coupled fluidstructure case is more difficult but also more critical, as there are a greater number and variety of sources of numerical error and the results have more practical value. Model uncertainties (i.e. in the structural model parameters or the turb

47、ulence model) can be efficiently quantified with uncertainty quantification techniques developed in Delft. In this project they will be further developed and applied to aeroelastic problems._Experimental Data-Assimilation in CFD with Least-Square Finite Element Methods Current practice for flow anal

48、ysis is to either perform a computational simulation or an experiment. In case both are performed only end results are compared. We believe that much can be gained by truly combining both approaches in one rigorous methodology. As the Aero Group in delft both has an experimental as well as a numeric

49、al section, there lies an opportunity. Integration of modern CFD and experimental capabilities for aerodynamic analysis has the potential for enormous synergistic effects. The usefulness of experimental data could be enhanced greatly by computing values that can not be directly measured (e.g. obtain

50、ing pressure and boundary information from PIV velocity data), and the accuracy and reliability of simulation could be improved by incorporating experimental information (particularly with respect to turbulence modeling). However there is currently no general framework for performing this assimilati

51、on of experimental data. This PhD will concentrate on one possible approach based on the LeastSquares Finite Element Method (LSFEM). This method allows the flexible introduction of additional constraints on the numerical discretization in an appropriate and meaningful way. The overdetermined system

52、is then solved in a leastsquares manner. The accuracy of the experimental input information can be rigorously accounted for by weighting. The finite element context makes highorder accuracy, adaptation and error estimation possible. After its development, the data assimilation method is applied to a

53、nalyse steady and unsteady flows around airfoils. Experimental PIV data are available._Active flow separation control using plasma actuatorsIn the design of future transport aircraft the need for high fuel efficiency aircraft over the complete flight envelope is of crucial importance. The cruise con

54、dition requires further improvement in the development of low drag designs. To enable a reduction of the induced drag generated by the wings application of light weight structures is inevitable. Hence smooth wing designs with limited number of moving parts is required. The profile drag of these desi

55、gns may be reduced by postponement boundary layer transition through the applications of so called Dielectric-Barrier-Discharge (DBD) plasma actuators. Currently a research project on this topic is being performed within the aerodynamics group of the Faculty of Aerospace Engineering. However in the

56、low speed, high lift regime, the maximum lift that can be attained is the limiting factor through the occurrence of flow separation on either the main wing of the extended flap. To enable a further performance improvement of conventional fowler flap designs as well as novel flapless future wing desi

57、gns, the application of plasma flow control actuators will investigated. The project will be performed both numerically and experimentally and is based on experience with single DBD actuators that was recently obtained in the aerodynamics labs of the faculty. High Reynolds and Mach number tests are

58、foreseen in larger wind tunnel facilities of DNW at a later stage. This project will be performed in close cooperation with: NLR, the Dutch Aerospace Laboratory Dassault Aviation / AirBus NeqLab b.V. _Reduced-Order Models for Wall-Bounded Turbulent Flow Control(S. J. Hulshoff, Aerodynamics Group, TU

59、 Delft)Wall-bounded turbulent flows are widespread in engineering applications, and have substantial negative economic impact due to their high rates of energy dissipation. Consequently, there is considerable motivation to develop microscale sensor and control systems which canreduce turbulent energ

60、y dissipation 2. However, due to the limitations inherent in turbulent flow characterisation using only surface measurements, such systems require accurate reduced-order flow models in order to become fully effective.The standard approach to reduced-order modelling is to determine a modal expansion