{"paper":{"title":"Elastic wave propagation governs impulse enhancement in pulsed jets through flexible nozzles","license":"http://creativecommons.org/licenses/by/4.0/","headline":"Flexible nozzles increase pulsed jet impulse by 62% through elastic wave timing.","cross_cats":[],"primary_cat":"physics.flu-dyn","authors_text":"Chandan Bose, Daehyun Choi, Paras Singh, Saad Bhamla","submitted_at":"2026-05-17T08:22:34Z","abstract_excerpt":"Inspired by cephalopod jet propulsion through compliant funnels, this study investigates elastic wave propagation and energy exchange in passively deforming cylindrical nozzles through three-dimensional, two-way fluid-structure interaction simulations. Flexible nozzles with varying stiffness ($Eh = 75 - 500~\\mathrm{N\\,m^{-1}}$, where $E$ and $h$ are Young's modulus and nozzle thickness, respectively) are subjected to a pulsatile jet inflow at $Re \\sim 4000$. Increasing nozzle flexibility reduces the deformation-wave speed in accordance with Moens-Korteweg scaling, thereby prolonging the nozzle"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"For the most flexible nozzle, the primary vortex-ring circulation increases by 52.13%, the vortex convection distance by 9.00%, and the peak outlet kinetic energy flux by a factor of 4.62 compared with a rigid nozzle. These effects collectively yield a 61.92% increase in total hydrodynamic impulse.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The simulations with chosen stiffness range (Eh = 75-500 N m^{-1}) and Re ~4000 accurately isolate elastic wave effects as the dominant driver of impulse enhancement without significant influence from unmodeled factors such as material nonlinearity, boundary conditions, or numerical dissipation.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Flexible nozzles in pulsed jets increase hydrodynamic impulse by 61.92% through elastic wave propagation that delays expansion, enhances entrainment and energy storage, and boosts acceleration during contraction.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Flexible nozzles increase pulsed jet impulse by 62% through elastic wave timing.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"e5ec1914aca0b0771c28e691ebdc057b4049f84325a40a844761baf6430443d7"},"source":{"id":"2605.17319","kind":"arxiv","version":1},"verdict":{"id":"d071b833-facc-4584-8835-8864dedfc83f","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-19T23:16:21.839929Z","strongest_claim":"For the most flexible nozzle, the primary vortex-ring circulation increases by 52.13%, the vortex convection distance by 9.00%, and the peak outlet kinetic energy flux by a factor of 4.62 compared with a rigid nozzle. These effects collectively yield a 61.92% increase in total hydrodynamic impulse.","one_line_summary":"Flexible nozzles in pulsed jets increase hydrodynamic impulse by 61.92% through elastic wave propagation that delays expansion, enhances entrainment and energy storage, and boosts acceleration during contraction.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The simulations with chosen stiffness range (Eh = 75-500 N m^{-1}) and Re ~4000 accurately isolate elastic wave effects as the dominant driver of impulse enhancement without significant influence from unmodeled factors such as material nonlinearity, boundary conditions, or numerical dissipation.","pith_extraction_headline":"Flexible nozzles increase pulsed jet impulse by 62% through elastic wave timing."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2605.17319/integrity.json","findings":[],"available":true,"detectors_run":[{"name":"doi_title_agreement","ran_at":"2026-05-19T23:31:20.145038Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"doi_compliance","ran_at":"2026-05-19T23:31:00.640758Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"claim_evidence","ran_at":"2026-05-19T22:01:57.772894Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"ai_meta_artifact","ran_at":"2026-05-19T21:33:23.750366Z","status":"skipped","version":"1.0.0","findings_count":0}],"snapshot_sha256":"8c3e068e656cabdbcdba049ed2c06ddc1583e52a30e463b1682eb47554d239b4"},"references":{"count":22,"sample":[{"doi":"","year":2018,"title":"A separated vortex ring underlies the flight of the dandelion , author=. Nature , volume=. 2018 , publisher=","work_id":"f232a982-b815-4c3e-921e-bf748bce5643","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2022,"title":"Journal of Fluid Mechanics , volume=","work_id":"b7d8e189-8a54-4184-8257-c42956cbccf0","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2024,"title":"Journal of Fluid Mechanics , volume=","work_id":"96beac95-b054-4d03-9bcb-1aab60044b4b","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2025,"title":"Journal of Fluid Mechanics , volume=","work_id":"07045b7d-3dc2-4fc1-a9d7-ceaf2c80f311","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2022,"title":"Journal of Fluid Mechanics , volume=","work_id":"9e00dfb9-eabd-4353-9783-8011a99aea80","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":22,"snapshot_sha256":"d1a30925c555a7184ce63b0e2167d9094fa00e8f03562cc39af061b220d42c15","internal_anchors":0},"formal_canon":{"evidence_count":1,"snapshot_sha256":"a5bd70bf9e06b4f50679dc3738bb0ede6a9f24ffdb326e2fed2cdff838bdc316"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}