Application of a JPEG 2000-Based Data Compression Algorithm to DNS of Compressible Turbulent Boundary Layers Up to $$Re_\theta =6600$$ R e θ = 6600

This paper presents a performance analysis of the compression library BigWhoop applied to compressible-turbulent-boundary-layer data obtained by direct numerical simulation (DNS). The DNS data are computed for a Mach number of $$M=2.0$$ M = 2.0 and cover a Reynolds-number range of $$Re_\theta =300$$ R e θ = 300 to 6600. Including six flow-field variables, each time step has a data size of about 1 TB. Mainly evaluated for the streamwise velocity component, various compression rates are tested for the flow field of one single time step as data post processing. It is shown that DNS data compressed up to 1 : 200 yield a maximum absolute error of $$0.2\%$$ 0.2 % for the entire domain. This is still accurate enough to reliably perform flow-field investigations in the outer layer of the turbulent boundary layer, notably considering that the maximum error only occurs with extremely low probability. The no-slip wall boundary condition forces the velocity down to zero, and thus the relative error, i.e. the absolute error divided by the local velocity, is significantly larger in the near-wall region. Hence, for flow-field investigations depending on important wall values like the skin friction for instance, the maximum compression ratio should be limited to about 1 : 100, keeping the maximum relative error below $$1\%$$ 1 % in the near-wall region.