The Nature of Things - A Design Narrative

The subject of this narrative is the creative process. It concerns a young Chinese graduate who has studied in London. On the eve of her graduation ceremony she learns something important about her abilities. It is a vague hint of the way her creative life might develop, but many years must pass before she can practice her skills and express her understanding. The illustrated narrative is written in both English and Chinese

A numerical analysis of buoyancy-driven melting and freezing

A numerical investigation of transient natural convective heat transfer with coupled phase change is presented. The numerical model attempts to capture the solid-fluid interface using a fixed-grid solution and is applied to two pure substance cases found in published literature, one considering the melting of 95% pure Lauric acid and the other involving the freezing of water. The governing equations are solved in a manner such that if the temperature falls below the freezing isotherm then the convection terms in the equations of motion are effectively disengaged. Variations in the specific heat of the material are incorporated in order to account for the phase change. A non-Boussinesq approach is considered which accounts for any density extrema in the flow, particularly for the density inversion found in water. In both of the cases considered the phase change occurs between fixed temperature boundaries and Rayleigh numbers rest well within the laminar flow regime. From the results obtained it is demonstrated that a relatively simple numerical technique can be applied to capture the physics of buoyancy-driven melting and freezing and that the results are in reasonable concurrence with experimental data

Study of a regenerative pump using numerical and experimental techniques

Regenerative pumps are the subject of increased interest in industry as these pumps are low cost, low specific speed, compact and able to deliver high heads with stable performance characteristics. The complex flow-field within the pump represents a considerable challenge to detailed mathematical modelling as there is significant flow separation in the impeller blading. This paper presents the use of a commercial CFD code to simulate the flow within the regenerative pump and compare the CFD results with new experimental data. The CFD results demonstrate that it is possible to represent the helical flowfield for the pump which has only been witnessed in experimental flow visualisation until now. The CFD performance results also demonstrate reasonable agreement with the experimental tests. The CFD models are currently being used to optimise key geometric features to increase pump efficiency

Fluent User Defined Function: WindCube_comp_sim : NORSEWInD Report UOSNW013

This report describes the Fluent User Defined Function WindCube_comp_sim used to interrogate FLUENT a Fluent data set by simulating the operation of a LeoSphere Windcube LiDAR. The user defined function is contained in the program lidar.c (version 1.06) which has been written in the C programming language. This report contains a listing of the user defined function, describes its method of operation and presents a validation of the analysis process. The report also includes a description of the output data file formats

Feasibility Study of using a LiDAR in the complex flowfield of an offshore platform, to measure wind shear profile.

Offshore wind is the major growth area in the wind industry sector today. However, there remains a key, fundamental missing element - a thorough understanding of the offshore wind climatology and likely wind resource. In 2008 the EU FP7 funded project NORSEWInD was created with a remit to deliver offshore wind speed data at a nominal project hub height acquired in offshore locations in the North, Baltic and Irish seas. Part of the overall NORSEWInD project was the use of LiDAR remote sensing (RS) systems mounted on offshore platforms to measure wind velocity profiles at a number of locations offshore. The data acquired from the offshore RS measurements was fed into a large and novel wind speed dataset suitable for use by the wind industry. The data was also fed into key areas such as forecasting and MESOSCALE modelling improvements. One significant problem identified was the effect of platform interference effects on the RS data. Therefore, part of the fundamental research incorporated into the NORSEWInD project was an investigation into the possible extent and effect of the interference on the measured data from the various mounting platforms. This paper reports on the Computational Fluid Dynamics (CFD) modelling of the wind flows over the platforms and the verification of the CFD models by the use of sub scale wind tunnel models employing three dimensional Constant Temperature Anemometers (CTAs) to measure local velocity vector data

Computational and Experimental Study on the effect of flow field distortion on the accuracy of the measurements made by anemometers on the Fino3 Meteorological mast

This paper reports on the experimental and computational modelling of the flow field around the FINO3 mast and provides an estimate of the amount of distortion that might be expected on instrumentation mounted on such a large structure. The open source C++ toolbox OpenFOAM was used for the CFD analysis. In order to validate the CFD model, experimental work was carried out in an open section wind tunnel using hot wire anemometry to measure the velocity profile around a sub-scale model of part of the FINO3 mast. The experimental data are in good agreement with the data from the CFD simulatio

User Defined Function: lidar_3D : NORSEWInD Report UoSNW006

This report describes the User Defined Function Lidar_3D used to interrogate FLUENT data files to provide the relevant data for the MathCAD LiDAR simulation program. The UDF was written in the C programming language and compiled using Microsoft visual studio 2008. This report contains a listing of the program (version 1.03). This report contains a description of the methodology required to compile the UDF so that it may be called by an "execute on demand" call from FLUENT. The report also includes a description of the input and output data file formats

Introducing instrumentation and data acquisition to mechanical engineering students using LabVIEW

For several years, LabVIEW has been used within the Department of Mechanical Engineering at the University of Strathclyde as the basis for introducing the basic concepts and practice of data acquisition, and more generally, instrumentation, to postgraduate engineering students and undergraduate project students. The objectives of introducing LabVIEW within the curriculum were to expose students to instrumentation and experimental analysis, and to create courseware that could be used flexibly for a range of students. It was also important that staff time for laboratory work be kept to manageable levels. A course module was developed which allows engineering students with very little or no previous knowledge of instrumentation or programming to become acquainted with the basics of programming, experimentation and data acquisition. The basic course structure has been used to teach both undergraduates and postgraduates as well as laboratory technical staff. The paper describes the objectives of the use of LabVIEW for teaching, the structure of the module developed, and the response of students who have been subjected to the course, and how it is intended to expand the delivery to greater student numbers

Comparison of Zephir and Windcube measurements in the same complex flowfield

Offshore wind is the major growth area in the wind industry sector today. However, there remains a key, fundamental missing element - a thorough understanding of the offshore wind climatology and likely wind resource. In 2008 the EU FP7 funded project NORSEWInD was created with a remit to deliver offshore wind speed data at a nominal project hub height acquired in offshore locations in the North, Baltic and Irish seas. Part of the NORSEWInD project is the use of LiDAR remote sensing (RS) systems mounted on offshore platforms to measure wind velocity profiles. The data acquired from the offshore RS measurements are fed into a large wind speed dataset suitable for use by the wind industry. One significant problem identified was the effect of platform interference effects on the RS data. Another significant effect on the quality of the data produced was the method by which the wind speed and direction was acquired as the method by which LiDARs measure the wind vector is significantly different from a point measurement. Whilst this will have no effect in a homogeneous flow field if there is significant flow distortion, which might be found in close proximity to a large structure or in complex terrain, then the effect of this spatially averaged measurement might cause a significant deviation from a point measurement. This paper reports on the modelling of two different types of LiDAR, the Natural Power ZephIR and the Leosphere Windcube, in a computational fluid dynamics simulation of the flow around a large offshore structure. The paper discusses the difference in the measured wind vector when compared to a point measurement at the measurement height