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We introduce NRPyElliptic, an elliptic solver for numerical relativity (NR) built within the NRPy+ framework. As its first application, NRPyElliptic sets up conformally flat, binary black hole (BBH) puncture initial data (ID) on a single numerical domain, similar to the widely used TwoPunctures code. Unlike TwoPunctures, NRPyElliptic employs a hyperbolic relaxation scheme, whereby arbitrary elliptic PDEs are trivially transformed into a hyperbolic system of PDEs. As consumers of NR ID generally already possess expertise in solving hyperbolic PDEs, they will generally find NRPyElliptic easier to tweak and extend than other NR elliptic solvers. When evolved forward in (pseudo)time, the hyperbolic system exponentially reaches a steady state that solves the elliptic PDEs. Notably NRPyElliptic accelerates the relaxation waves, which makes it many orders of magnitude faster than the usual constant-wavespeed approach. While it is still ∼12x slower than TwoPunctures at setting up full-3D BBH ID, NRPyElliptic requires only ≈0.3% of the runtime for a full BBH simulation in the Einstein Toolkit. Future work will focus on improving performance and generating other types of ID, such as binary neutron star.
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INTIACC: A 32-bit Floating-Point Programmable Custom-ISA Accelerator for Solving Classes of Partial Differential Equations
We propose a numerical integration accelerator (INTIACC) that speeds up the solution of partial differential equations (PDEs) for scientific computing. In contrast to recent works, INTIACC applies to a variety of PDEs and boundary conditions, has enhanced nonlinear function capability, supports high-order integration algorithms, and uses floating-point arithmetic for orders of magnitude smaller solution error. With all the benefits, our test chip still achieves 40X speed-up over prior accelerators and orders of magnitudes over CPU and GPU based systems.
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- Award ID(s):
- 1840763
- PAR ID:
- 10464827
- Date Published:
- Journal Name:
- ESSCIRC 2022- IEEE 48th European Solid State Circuits Conference (ESSCIRC)
- Page Range / eLocation ID:
- 349 to 352
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ESSCIRC55480.2022.9911441
