Namespace Example_superposition

The second script is to use the superposition with the generated file.

Pre-computing the 8 simulations

const arch = require('arch.node')
const io   = require('@youwol/io')
const df   = require('@youwol/dataframe')
const math = require('@youwol/math')
const geom = require('@youwol/geometry')
const fs   = require('fs')

const model = new arch.Model()
model.setMaterial ( 0.25, 30e9, 2000 )
model.setHalfSpace( true )

const dataframe  = io.decodeGocadTS( fs.readFileSync('surface.ts', 'utf8') )[0]

const chamber = new arch.Surface(
    dataframe.series.positions.array,
    dataframe.series.indices.array
)
chamber.setBC("dip",    "free", 0)
chamber.setBC("strike", "free", 0)
chamber.setBC("normal", "free", 0)
model.addSurface( chamber )

const remote = new arch.UserRemote() // will be set later on
model.addRemote( remote )

const solver = new arch.Forward(model, 'parallel', 1e-8, 200)
solver.setNbCores(32)              // e.g., using a AMD Ryzen 9 5950X 16x
solver.setAutoReleaseMemory(false) // Important for speed consideration

// ------------------------------------------------

// [minX, minY, minZ, maxX, maxY, maxZ]
const bounds = model.bounds()
const d = Math.max(bounds[3]-bounds[0], bounds[4]-bounds[1])

const grid = geom.generateRectangle({
    a: 2*d,
    b: 2*d, 
    na: 50, 
    nb: 50, 
    center: [(bounds[3]+bounds[0])/2, (bounds[4]+bounds[1])/2, 0] // at z=0
})
const obs = grid.series.positions.array

// [xx, xy, xz, yy, yz, zz, density, shift]
const nbSimulations = 8

const doSimulation = index => {
    const alpha = new Array(nbSimulations).
        fill(0).map( (v,i) => i===(index-1) ? 1 : 0 )
    console.log(`=======> Doing simulation  + ${alpha}` )

    remote.setFunction( (x,y,z) => {
        return [
            alpha[0]*Math.abs(z), // xx
            alpha[1]*Math.abs(z), // xy
            alpha[2]*Math.abs(z), // xz
            alpha[3]*Math.abs(z), // yy
            alpha[4]*Math.abs(z), // yz
            alpha[5]*Math.abs(z)  // zz
        ]
    })
    // Pressure in the cavity
    chamber.setBC( "normal", "free", (x,y,z) => alpha[6]*Math.abs(z) + alpha[7] )

    solver.run()
    const solution = new arch.Solution(model)

    grid.series[`U${index}`] = df.Serie.create({
        array: solution.displ(obs),
        itemSize: 3
    })

    grid.series[`S${index}`] = df.Serie.create({
        array: solution.stress(obs),
        itemSize: 6
    })
}

for (let i=1; i<=nbSimulations; ++i) {
    doSimulation(i)
}

fs.writeFile('simulations.ts', io.encodeGocadTS(grid), 'utf8', err => {})

Using the superposition for realtime computation

// Note that Arch is no longer necessary :-)
const io     = require('@youwol/io')
const geo    = require('@youwol/geophysics')
const fs     = require('fs')

const dataframe  = io.decodeGocadTS( fs.readFileSync('simulations.ts', 'utf8') )[0]

//             xx   xy   xz   yy    yz   zz   rho pe
const alpha = [72,  2,   11,  110,  100, 1,   5,  3 ]

dataframe.series['displ'] = geo.forward.attribute({
    simulations: dataframe,
    name: 'U',
    alpha,
    startIndex: 1
})

dataframe.series['stress'] = geo.forward.attribute({
    simulations: dataframe,
    name: 'S',
    alpha,
    startIndex: 1
})

const bufferOut = io.encodeGocadTS(dataframe)
fs.writeFile('example.ts', bufferOut, 'utf8', err => {})