unusually severe and long lasting, were used to construct the boundary conditions for the simulation. A cloudless January 15 with a medium wind speed (0.5m/s in 8m above ground) was chosen as the worstcase scenario date for the simulation. With this set-up, the simulated day's irradiation is at its highest, and the amount of cooling provided by wind is minimal. The simulation began at 9 a.m. and ended at 10 p.m. Just the average extreme heat hour results, i.e., 2 PM, are considered in the discussion that follows. The scale of the plan changes depending on how many pixels are used in the program. For the selected area to fit in the model of 180 X 200, each pixel represents 4 meters in the plan. The true condition file was created, and four different scenarios were proposed around it. The true condition file is the one that is the closest to the current situation, while the other scenarios use mitigation strategies that promote the use of renewable energy. Simulator settings were applied once the models had been created in the map area and transferred into the simulation settings. Pavement and asphalt are included in the map region along with a variety of building types and heights. The 3D model is being created at the same time as the 2D plan in the case. Because the buildings' heights vary, a scale factor has been used to the 3D to provide a lighter model. Using the ENVI-Area met's Input file editor, the model was rotated by -20° clockwise to match the main development direction of the roadways. A thicker grid towards the ground allows for higher precision in identifying edge effects since the grid has a fixed spacing on the x and y - axis but is telescopic on the z axis (1.20 m is the mean value). As a result, the model's maximum height is 36 m (1.20 30 m). For the model to be numerically stable, the height of the highest building must be at least twice as high as this value. With three types of façade materials (Appendix) and a mix of good and moderate insulation at heights ranging from 18 meters to 36 meters, buildings in the model are taken into consideration for the study. Different plant varieties have been used to model the vegetation. For the most part, the area has been paved with typical soil, with the significant exception of the main road, which is paved with asphalt. All the models use the same basic inputs for their simulations. However, because of the proposed complexity, the values for each case model differ. Each model had a total 6-hour profile set for the same period, and the simulations predicted 48 hours of downtime. Due to the large size of each model, the simulation took on average 50 hours to finish.
Software Limitations ENVI-met is continually being developed, and it is getting new features all the time. Although it comes close to accurately simulating reality, ENVI-met does have certain (significant) drawbacks. The following is a brief list of ENVI-met's most significant limitations: • •
Precipitation in model: ENVI-met is unable to simulate precipitation or temperatures below zero degrees Radiation: In the model area, the radiative fluxes have been neglected. - The above and down diffuse radiation scattering is termed isotropic.
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