{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:GMX5HFZ2LJC35XKTIYVBEBQMP2","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"fee29bee0ebb630bcfbdb682175cdb76b67038443d9459f480fc2b56a4a7b117","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-12-05T23:14:12Z","title_canon_sha256":"5d719b98638b8998ee6ac91fb0c673719ea6cb0d0e6a7c5d02435e370bdd0a6e"},"schema_version":"1.0","source":{"id":"1812.02265","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1812.02265","created_at":"2026-07-05T02:07:43Z"},{"alias_kind":"arxiv_version","alias_value":"1812.02265v1","created_at":"2026-07-05T02:07:43Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1812.02265","created_at":"2026-07-05T02:07:43Z"},{"alias_kind":"pith_short_12","alias_value":"GMX5HFZ2LJC3","created_at":"2026-07-05T02:07:43Z"},{"alias_kind":"pith_short_16","alias_value":"GMX5HFZ2LJC35XKT","created_at":"2026-07-05T02:07:43Z"},{"alias_kind":"pith_short_8","alias_value":"GMX5HFZ2","created_at":"2026-07-05T02:07:43Z"}],"graph_snapshots":[{"event_id":"sha256:631bdb71522246b4c16d39cd977cee12c7c1bff9b38e3d5d257605a6955e073e","target":"graph","created_at":"2026-07-05T02:07:43Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/1812.02265/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Progress in roughness research, mapping any given roughness geometry to its fluid dynamic behaviour, has been hampered by the lack of accurate and direct measurements of skin-friction drag, especially in open systems. The Taylor--Couette (TC) system has the benefit of being a closed system, but its potential for characterizing irregular, realistic, 3-D roughness has not been previously considered in depth. Here, we present direct numerical simulations (DNSs) of TC turbulence with sand grain roughness mounted on the inner cylinder. The model proposed by Scotti (\\textit{Phys. Fluids}, vol. 18, 0","authors_text":"Daniel Chung, Detlef Lohse, Pieter Berghout, Richard J.A.M. Stevens, Roberto Verzicco, Xiaojue Zhu","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-12-05T23:14:12Z","title":"Direct numerical simulations of Taylor--Couette turbulence: the effect of sand grain roughness"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1812.02265","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:a5b7b2c27b386649e5ff3d84cbf2ed648d1f952316fe7ceac146a59d0b894d9a","target":"record","created_at":"2026-07-05T02:07:43Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"fee29bee0ebb630bcfbdb682175cdb76b67038443d9459f480fc2b56a4a7b117","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-12-05T23:14:12Z","title_canon_sha256":"5d719b98638b8998ee6ac91fb0c673719ea6cb0d0e6a7c5d02435e370bdd0a6e"},"schema_version":"1.0","source":{"id":"1812.02265","kind":"arxiv","version":1}},"canonical_sha256":"332fd3973a5a45bedd53462a12060c7e84715e4c68f702c0a279e71f898c4ef6","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"332fd3973a5a45bedd53462a12060c7e84715e4c68f702c0a279e71f898c4ef6","first_computed_at":"2026-07-05T02:07:43.044849Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T02:07:43.044849Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"bULTDvOCD6GhOJm5j694vW4YlDCq3fp2ocacVR29cdQc4KtnIrlqBEN9c+iWHaoop8s++NmswmyL1LCeDNdjBg==","signature_status":"signed_v1","signed_at":"2026-07-05T02:07:43.045257Z","signed_message":"canonical_sha256_bytes"},"source_id":"1812.02265","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:a5b7b2c27b386649e5ff3d84cbf2ed648d1f952316fe7ceac146a59d0b894d9a","sha256:631bdb71522246b4c16d39cd977cee12c7c1bff9b38e3d5d257605a6955e073e"],"state_sha256":"62872240441ef0d7de2e22b8f0b4ca6e1b39334854a07c86ba7ad45650bbfffb"}