{ "description": "The bell cymbal (cymbal-bell-v1 geometry, material and listener) hit once with the challenge's stick pulse (1000 N peak, 1 ms) at t = 0.1 s but at 0.64 R, mid-bow, at x = 130.0 mm on the x axis. Same solver and grid as the top of the bell chain (4 mm, 300 symmetric shell modes, two steps per sample), on the GPU; the strike normalization is recomputed for the local surface. Peak 54.6 Pa at the listener; rms 8.90 Pa over 0.1 to 0.6 s and 0.41 Pa over 1 to 2 s; spectral centroid 6283 Hz early and 725 Hz later. Scale 160 Pa.", "challenge_geometry": "cymbal-bell-v1", "strikes": [ { "t": 0.1, "force": 1000.0, "duration": 0.001, "x": 0.13, "y": 0.0 } ], "parameters": { "grid_spacing_m": 0.004, "cells": 8112, "n_dof": 33268, "transverse_modes": 300, "basis_even_in_y": true, "airy_modes": 300, "oversampling": 2, "dt_s": 1.0416666666666666e-05, "highest_transverse_mode_hz": 14038.5 }, "signal_scale_pa": 160.0, "peak_pa": 54.6, "rms_pa": { "0.1-0.6 s": 8.896, "1-2 s": 0.41 }, "spectral_centroid_hz": { "0.1-0.6 s": 6283, "1-2 s": 725 }, "timing_seconds": 646.827, "hardware": "Intel(R) Xeon(R) w5-3435X (32 threads), numpy/scipy for the setup; coupling tensor and time stepping on NVIDIA RTX 6000 Ada Generation (PyTorch 2.14.0+cu130)", "note": "Experiment with a strike position; not a solution of any challenge." }