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Modern Engineering Design involves the deployment of many computational tools. Research on challenging real-world design problems is focused on developing improvements for the engineering design process through the integration and application of advanced computational search/optimization and analysis tools. Successful application of these methods generates vast quantities of data on potential optimum designs. To gain maximum value from the optimization process, designers need to visualise and interpret this information leading to better understanding of the complex and multimodal relations between parameters, objectives and decision-making of multiple and strongly conflicting criteria. Initial work by the authors has identified that the Parallel Coordinates interactive visualisation method has considerable potential in this regard. This methodology involves significant levels of user-interaction, making the engineering designer central to the process, rather than the passive recipient of a deluge of pre-formatted information.In the present work we have applied and demonstrated this methodology in two different aerodynamic turbomachinery design cases; a detailed 3D shape design for compressor blades, and a preliminary mean-line design for the whole compressor core. The first case comprises 26 design parameters for the parameterisation of the blade geometry, and we analysed the data produced from a three-objective optimization study, thus describing a design space with 29 dimensions. The latter case comprises 45 design parameters and two objective functions, hence developing a design space with 47 dimensions. In both cases the dimensionality can be managed quite easily in Parallel Coordinates space, and most importantly, we are able to identify interesting and crucial aspects of the relationships between the design parameters and optimum level of the objective functions under consideration. These findings guide the human designer to find answers to questions that could not even be addressed before. In this way, understanding the design leads to more intelligent decision-making and design space exploration. Downloaded by ROKETSAN MISSLES INC. on February 8, 2015 | http://arc.aiaa.org |

A pattern recognition technique has been applied to simultaneously sampled multipoint hot-wire anemometry data obtained in the far wake of a circular cylinder. Data from both the streamwise fluctuating velocity field and the temperature field have been analysed employing a computer code that uses a correlation approach to automatically detect and ensemble average flow patterns and patterns for mean-square fluctuations. Statistical tests then allow the significance and contribution to the turbulence intensity of the detected structures to be evaluated. This procedure has been used to infer the three-dimensional topology of the double-roller eddies previously identified in the far-wake region and to relate these to the motions responsible for entrainment. It appears that the two types of motion are not independent, but are linked together, forming parts of horseshoe vortex structures which account for at least 40% of the total turbulence energy. These structures originate near the centre of the flow, may extend across the centreline and typically occur in groups of about three. The resulting picture of the flow dynamics is related to the conclusions drawn from similar data by other workers and a possible regeneration mechanism is presented. The addition to the code of a fine-scale activity indicator, the choice of which is discussed in some detail, has allowed the relationship between these energetic large-scale motions and smaller eddies to be investigated. It seems that the most intense fine-scale activity is associated with the vortical cores of the double-roller eddies. It is shown that this observation is consistent with the concepts of ‘isotropy’ and ‘spotiness’ of the dissipative scales. It also suggests that the horseshoe vortices loose energy both to their own secondary instabilities and to smaller scales resulting from the breakup of other highly strained large eddies.