UltraWave: An Open-source Multi-GPU Full-wave Simulator for Acoustic and Elastic Wave Scattering in 3-D Heterogeneous Media.

Fast and accurate three-dimensional (3-D) full-wave ultrasound simulation is critical for applications such as medical imaging, tissue characterization, and synthetic data generation for machine learning. However, computational demands escalate prohibitively at higher resolutions. To address this challenge, we developed UltraWave, an open-source, multi-GPU-accelerated full-wave simulator for acoustic and elastic wave scattering in 3-D heterogeneous media. UltraWave incorporates advanced capabilities including media inhomogeneity, elastic wave propagation, power-law frequency-dependent absorption, and perfectly matched layers. To rigorously validate simulation accuracy, we also developed a companion code suite that computes the scattered waveforms in both time and frequency domains using analytical solutions from scattering theory for several standard scattering scenarios, enabling quantitative benchmarking of numerical simulators and addressing a critical gap in standardized validation tools. We evaluated UltraWave against the widely used k-Wave simulator, and demonstrated its accuracy, computational efficiency, and scalability. For a 3-D elastic scattering simulation, UltraWave achieved equivalent accuracy to k-Wave while reducing the runtime from 8 hours (k-Wave on a single GPU; multi-GPU capability is currently unavailable in k-Wave) to 20 minutes (UltraWave on 4 GPUs). UltraWave offers a powerful and scalable tool for high-resolution wave propagation and scattering simulations in biomedical applications.