3003 W CASINO RD PAINT HANGAR BOUNDARIES 2023-07-20

4 • DI Geminus Boeing Project Contract No.EVE-16-2929 Technology Development CEI Project No. 160731 3 CFD-Based Analysis Validation (Case 1) 3.1 CFD Model Validation Approach & Methodology The goal of validation of the CFD model is to ensure that (a) there are no gross errors in the model setup (particularly the supply airflow and exhaust specifications); (b) the constructed CFD model is capable of sufficiently accurately predicting the observed/measured airflow distribution around an 777-300ER aircraft inside the 45-04 hangar during the measurements described in the TAB report [5]; and (c) computed % of LEL values for the 45-04 are conservatively computed and are consistent with measurements of % of LEL at various points during painting operations in the 45-04. Exact comparisons and validation against 45-04 TAB airflow data and 45-04 % of LEL measurements are not possible due to ambiguities in the measurement details, exact internal configuration of the paint hangar at the time of measurements, daily environmental conditions (which were not recorded and vary throughout the year), exact conditions of paint applications, etc. Thus two general validation cases were specified by Boeing [23], one for general air flow comparison (Case 1/Scenario 1) and qualitative comparison of predicted to measured % of LEL levels taken in the 45-04 under similar conditions (Case 1/Scenario 2). This is the same validation procedure followed in the 45- 01 Paint Hangar analysis [1] and 45-03 Paint Hangar analysis [2]. 3.2 Pre-Modification Airflow Pattern Predictions & % of LEL Comparison Airflow directional velocity measurements at key locations around the aircraft are available in the October 2005/2006 TAB Report performed by Neudorfer Engineers, Inc. [5]. CFD Case 1, Scenario 1 replicates as best as possible the hangar conditions present during these airflow measurement tests so that computed airflow velocities can be quantitatively compared to measured values. Supply and exhaust flow rates were also measured in the TAB report and are incorporated into Case 1 scenarios. No paint activity was in progress when these data were collected so CFD Case 1, Scenario 1 has no paint guns or stacker cranes in the model (i.e, they were "parked" or retracted in some un-recorded, but typically out-of-the-way location during the measurements). Additional model verification was performed in Case 1/Scenario 2 by adding stacker cranes and active paint guns. Volatile vapor concentrations are computed in this scenario. Measured % of LEL (or PPM) data is available for Hangar 45-04, and are contained in [24] and [25]. The same paint procedure is used for Case 1 that is used for Case 2 and Case 3 (see Table 1). The following model components differ between Case 1 and Case 2: • Hangar ventilation supply and exhaust — Additional supply and exhaust locations added in Case 2 that are not present in Case 1. • Ventilation modes — Case 1 uses measured airflow rates for supply and exhaust which differ from the ventilation modes in Case 2. • Aircraft—777-300ER used in Case 1, 777-9X used in Case 2. • Wing stands, horizontal stabilizer platforms, empennage stands—Modifications to these platforms for Case 2 that are not present in Case 1. • Stacker crane and paint gun locations —These are placed in different locations for Case 1 and 2 but are in the same position relative to each aircraft. 25