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Ge i n u s Boeing Project Contract No.EVE-16-2929 <br /> Technology Development CEI Project No. 160731 <br /> See Figure 14 for a layout of stacker crane locations around the 777-300ER aircraft for Case <br /> 1/Scenario 2. See Figure 12 for spray gun details and orientations. <br /> ttsapporik <br /> r � <br /> I <br /> Figure 14: Stacker Crane (And Associated Painting) Locations On 777-300ER For Case <br /> 1 CFD Simulations <br /> 3.2.1 45-04 Pre-Modification CFD Model Configuration <br /> Based on the 3D CAD representation of the 45-04 hangar, pre-modification air supply and <br /> exhaust ducts locations, pre-modification wing stands, tail stands, empennage stand, and 777- <br /> 300ER aircraft representation, a flow volume (building volume minus the internal solid <br /> components of the aircraft, wing/tail/empennage stands, etc.) was developed for the airflow to be <br /> solved (see Figure 15). The gratings present on the wing, tail and empennage stands were <br /> modeled as porous solids of the same thickness and was assigned an empirically-derived <br /> pressure drop normal to the grating (based on the amount of flow occlusion) and zero flow <br /> allowed in directions transverse to the normal — i.e. air is only allowed to flow through the open <br /> area of the grating as one would expect. The pressure drop of the grating is not very high, but it <br /> has the effect of behaving like a flow straightener. Also, major flow blockages from components <br /> below the grating were installed and consisted of light panels, structural supports, and the wing <br /> stand articulation components. Paint guns were numerically simulated as short small diameter <br /> cylinders with an air + overspray vapors with the correct mass flow emanating with an elliptical <br /> flow direction from a sub-patch on the cylinder end face to mimic the spray pattern of the actual <br /> spray gun as specified by the manufacturer under typical flow rate conditions. The specified <br /> (measured/balanced) mass flow rates on a per location basis were then set at the supply and <br /> exhaust locations. Leakage air (to make up for the difference in supply and exhaust flow rates) <br /> was determined to mainly emanate from the hangar door gaps, which have by far the largest <br /> leakage areas compared to any other access doors. <br /> 26 <br />