NUMERICAL ANALYSIS OF SURFACE CRACK GROWTH IN PRESSURIZED CYLINDERS UNDER CREEP CONDITION
Bibliographic record
Abstract
In the study of metal creep,more and more efforts are being devoted to the materials and structures containing defects.Surface crack shape variation is one of the important issues in the study of leak-before-break(LBB) procedure.However,little attention has been paid to creep crack growth of surface cracks by numerical simulation.In the present study,a numerical analysis has been conducted on a low alloy Cr-Mo steel cylinder subjected to internal pressure at high temperature,with semi-elliptical crack located at the inner surface.The stress intensity factors(SIFs) and creep crack driving force parameter C*-integrals,calculated by numerical methods,are compared with results from previous studies.Good agreement has been obtained by comparing SIF,which demonstrates the FE(finite elememnt) model is reliable.The empirical equations of C*-integral,however,may be inaccurate under some condition.Moreover,the creep crack growth described by C*-integral is investigated using three-dimensional finite element analyses and a step-by-step analysis procedure based on codes ABAQUS is illustrated.Finally,crack profile development,C*-integral variation,crack depth,crack length and remaining life prediction are presented by studying several cases of different initial aspect ratios.It is observed that under monotonic internal pressure,the magnitude of crack length increment decreases as the initial aspect ratio ranges from 1 to 1/6,which is always minor compared with the crack depth increment.The crack profiles vary approaching to semi-circles and the aspect ratios increase all the time whatever the initial aspect ratio would be.In the final stage of the analyses,the boundary effect has been observed in C*-integral calculations.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".