In the previous project, a grasshopper parametric model for the tensile fabric roof structure of the Olympiastadion in Munich was created. A few details were later added such as the posts, which could be added of subtracted parametrically as per the the number of raised points. Their heights could be modified as well.
The goal of this project, however is the design optimization of the structure on the basis of solar radiation. This shall be performed using Galapagos Evolutionary Solver and the Ladybug Environmental plugin.
ANALYZE MUNICH'S CLIMATE:
DBT, RH AND WIND SPEED:
The first step is to use the Ladybug plugin to generate the charts of the elements of climate (Munich). The charts for temperature, humidity and wind speed were generated although more could have been generated. To do this, the epw file for Munich was downloaded from the link energyplus.net/weather. This file was inserted in grasshopper using the 'file path' component.
Then the 'importepw' component (Ladybug) was linked to the filepath which uses the file to generate the information. From the 'importepw' component, the dry bulb temperature output was connected to the '3DChart' node. The chart colors, high-low bounds and the legend were modified as shown above. The relative humidity and the wind speed output were also fed into the same 3DChart component. The following are the result viewed in Rhino:
But we are concerned with the dry bulb temperature so that we can identify the hottest months of the year to which the structure is to be optimized. For this a high bound of 26 celsius (79F in red) and a low bound of 8 celsius ( 46F in blue) was set.
From the above, it is seen that the months from May to September are the hottest in Munich and the roof must curtail the sunlight in these months.
SUNPATH DIAGRAM
Similarly, the sunpath diagram of Munich could also be generated. The location and dry bulb temperature outputs of the 'importepw' component were connected into '_location' and 'AnnualHourlyData_' inputs of the 'sunpath' component. The results were seen below:
RADIATION ANALYSIS:
This was done to visualize the amount of radiation received on the ground with the structure as the shading device. The link to the epw file for Munich was connected '_epwfile' input of the 'genCumulativeSkyMtx' component. After that the following steps were taken as shown below and in this project we are interested in the months from May to September and in the hours from 10 AM to 5 PM.
Setting the toggle to 'True' generates the following result which is the amount of radiation received on the ground:
DESIGN OPTIMIZATION
The final task is to optimize the design using Galapagos. The objective is to minimize the solar radiation received on the ground (shown as the mesh on the base) using the tensile fabric structure as the shading device. This is to be achieved by rotating the structure along the z-axis and tilting it along x-axis. So the best rotation and tilt is to be determined here using Galapagos.
A tilt and a rotation component was added to the mesh roof structure. This shall serve as to the link to the 'Genome' of the Galapagos Evolutionary Solver whereas the 'totalRadiation' output of 'radiationAnalysis' component is linked to the 'Fitness'.
Next step is to run the simulation using Galapagos solver.
The above is a part of the result that was extracted. Due to the time taken to run the simulation, the solver was stopped at this point. The high density of the base mesh is causing the delay.
To complete the simulation, the base mesh was simplified (x=20 and y = 20 instead of 100 each). The following is the completed simulation at the 61st iteration though the best result is probably at the 7th iteration. The structure rotates and tilts towards south in the final iteration.
The link to the video:
