{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"c1fb01a77257b87fb2f838757d84040aa8e88bc92f43bcaf9d91a4fee666381f","created":"2026-10-03T07:18:04Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"adbcae414145ea9c3365eaa413358be93d400133664fd4606d6edd47d993a5fa","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"fluid.strat-rot.layering","kind":"phenomenon","literature_status":"open","n":"1","parents":[],"plain":"Stirring a fluid whose density increases smoothly with depth can produce a staircase of uniform layers separated by sharp steps. What sets the height of the steps and how they evolve is not understood.","posed_since":"1972","precise":"Stirring a linearly stratified fluid can produce a staircase of well-mixed layers separated by thin interfaces, through the Phillips (1972) mechanism in which the buoyancy flux decreases with increasing local gradient over some range. Predict the layer thickness $h$ as a function of $\\mathrm{Re}_{b}$, horizontal Froude number and Pr, and the rate of layer merging at long times.","problem_ref":null,"references":"","settled_by":"A theory predicting h and merger rates verified by forced stratified DNS and tank experiments over a decade of stirring strength.","status_note":"2025 simulations track layer and interface evolution over long times (arXiv:2512.08714); no theory predicts h.","title":"What sets the thickness of spontaneous layers in stirred stratified fluid?","topic_ref":"10bf729b197d5ee7bbcb1c2f468901326f7231ccc5c3ae2967db2e962f472a39"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"dd39af02fcc59ac3e1c1ed8a94b334ea0c5063b8455f7ae39716ca951b552050","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"02be34116030c1712bcac088e9528666c03bccd7c75d28c2683be2b1c2a30c02","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"6FghFq31D2F6ajj2f5shODdCqK__mFPnuI0cqEeZ3rjzKveNl0WcdgD1uIx4y5S22VA6EYpFbsL2kglyMhFoAw"},"schema":"pubphys.envelope/1"},"record_hash":"dd39af02fcc59ac3e1c1ed8a94b334ea0c5063b8455f7ae39716ca951b552050","leaf_index":1441}