The exploded axonometric of the MWT. 

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... design phase. These programs focus mainly on providing graphical representations for the qualitative analysis of wind flow, a user-friendly interface and the integration with other architectural CAM programs such as Autodesk Revit. Thus, one aim of this research was to understand the limits of the performance of these programs for visualizing and feeding back wind effects in various architectural design contexts for particular design typological problems (see Figure 1). To this end they were used in parallel with testing physical models using electronic sensing to gather data for analysis. The models tested both in the CFD and Miniature Wind Tunnel and sensing environments were of complex porous screens for microclimatic control of an indoor environment in an apartment building. Wind tunnel tests have existed since 1871 [7] and wind tunnel tests have been conducted for architectural purposes since the early 1890s [8]. Yet simulating the wind for architectural design is challenging - the dynamics in wind around buildings involves the turbulent nature of the atmospheric boundary layer [9]. The first wind tunnel studies focused on reproducing real wind flows in 12m long tunnels. Subsequent wind tunnels were designed to reproduce the atmospheric boundary layer with a section 2.4m wide, 2.15m height and 33m long [10]. Industrial scale wind tunnels are large and expensive facilities, may require advanced data acquisition systems and processing systems that require specialist training to operate [11-13]. Techniques of visualization used in wind tunnels include tracer methods of the airflow such as fog/smoke emission, the use of floating particles or gas bubbles. Other methods trace air movement patterns on model surfaces using dye or oils to draw wind patterns [14] i.e. the erosion technique [15]. In general they provide a qualitative approach to visualizing the pattern of wind vortices, separation flows, turbulence and changes of wind direction. Quantitative techniques typically involve the analysis of results after the experiment has taken place. Hot-wire anemometry, pressure transduced anemometry (such as a pitot static tube) or tracer methods (such as the particle image velocimetry (PIV) technique) require post analysis for the evaluation of the physical design [16]. It is feasible to note that these techniques could be used to provide near real-time visualizations of the wind. The physical wind sensing system using a MWT and MEMS provides near real-time digital visualizations of the wind, using transduced signals from hot-element anemometers [17,18]. Digital visualizations of scientific data can augment the real world with ̳real-time‘ qualitative representations that enhance communication within groups. For example, animations that depict wind flows around physical models of architectural form can help communicate the behaviors of complex wind phenomena across design teams where not all members have an extensive knowledge of wind dynamics. This holds true even when the representations are not as accurate as traditional methods of simulating wind flows, as demonstrated in the Tangible Teamwork Table (TTTHub) project [19]. Digital and physical representations were combined to communicate the complexity of wind flow dynamics for a team undertaking an exercise in urban planning [19]. In a similar manner, the augmentation of physical wind through the quantification of wind at strategic points in space around physical building models or building details can provoke productive design discussions. The use of physical models to test wind dynamics allows architects to experiment with complex designs and environmental patterns without needing to use advanced numerical simulation tools to verify their experiments. The use of miniature wind tunnels can allow designers to observe how the wind may interact with a complex screen configuration. The use of a MWT can inform the designer through various visualization techniques to aid the design process towards more desirable interior microclimatic conditions. The particular wind tunnel used in this study incorporated a microelectronic wind sensing system which allowed the users to observe how the screen may affect environmental parameters such as: the dynamics in air movement, temperature and relative humidity that may be produced by the simulation of rain. These kinds of experiments are much more feasible to conduct using physical means, such as the MWT, even if the simulated airflow does not match the full scale in situ conditions. The idea is to conduct these experiments with a platform of low cost technology that can gather digitally airflow data and visualize it with a graphical interface to provide real-time feedback for architects. The design and improvement of the MWT is a work-in-progress, experiments are being conducted to evaluate the performance of the MWT to an industrial scale wind tunnel. The MWT is designed to be portable and is constructed by hand (see Figure 2). All of its parts are provided as templates that can be cut using a laser cutter and quickly assembled without the need for any tools. It consists of a test chamber containing four modules. Each module has a dimension of 0.9m wide, 0.9m high and 0.6m long The tunnel walls consist of 8 sheets of 0.6m x 0.9m x 6mm MDF, 8 sheets of 0.6m x 0.9m x 3mm Acrylic. Laser cut 6mm MDF sheets were used for the structural frame. The vertical bracings were designed with two sections, which are then replicated — one corner section and one spanning section (8 of each are required per module). The lateral bracing requires one section type (16 are required per module). Connectors for the frame elements and between the modules are also required. In addition, four fans are installed in the inlet zone to produce a continuous airflow of approximately 4m/s. In general, the wind tunnel is not designed to reproduce full- scale wind flow conditions such as atmospheric boundary layer or turbulence intensity profiles. However, it presents a controlled and stable wind flow environment for reasonable observations of the dynamics in environmental parameters that, in situ, exist in a similar manner. The test domain and sensor configuration utilized for observing the effects of porous screens within the miniature wind tunnel had the following attributes (Figure 3):  0.3m wide, 0.3m high and 0.6m long Acrylic square sectioned tube  Centrally suspended within the MWT test section  0.3m wide by 0.3m high prototype screen to be placed at inlet  Outlet configured for three scenarios: open, closed and doorway-sized opening to simulate variations in cross ...