Variable nozzle turbine can enhance the transient response of engine through the regulation of nozzle opening. Under the operating condition characterized by high expansion ratio and small nozzle opening, strong unsteady shock waves tend to develop at the trailing edge of the nozzle blades. These shock waves introduce significant periodic loadings, which can result in high-cycle fatigue and eventual fracture of the rotor blades. This study investigates the unsteady flow characteristics within a representative variable nozzle turbine, with particular focus on the temporal and spatial evolutions of shock waves and their dynamic coupling with the rotor-stator system. It is found that both the intensity and the spatial structure of the shock waves exhibit periodic variation in response to rotor-induced disturbances. The pressure disturbance with a frequency of 10 kHz induces significant blade loading at 50% span of the rotor blade leading edge, whose maximum root mean square (RMS) amplitude is 17.45 kPa. It substantially increases the probability of high-cycle fatigue for the rotor blade leading edge. These findings can offer meaningful guidance for optimizing and controlling shock waves in variable nozzle turbines.

RANS CFD applied to 2D canonical shock wave turbulent boundary layer interaction

The pore and fracture structure evolution and fractal characteristics of coal under the coupling effect of shock wave and acidification

Experimental and numerical investigation of shock wave propagation and thermal effects induced by thermobaric explosive detonation in corrugated steel-lined tunnels

Shock wave dynamics in a non-ideal dusty rotating gas influenced by magnetic field and radiation heat flux

Impact of bubble size distribution on shock wave attenuation by bubble curtains

Extracorporeal Shock Wave Therapy (ESWT) has emerged as a promising treatment modality in dentistry, offering non-invasive and effective solutions for various dental conditions. This review article aims to provide an overview of the current state of research on ESWT in dentistry, focusing on its applications, mechanisms of action and clinical outcomes. ESWT utilizes high-energy acoustic waves to stimulate biological tissues, promoting tissue regeneration, angiogenesis and pain relief. In dentistry, ESWT has been explored for the management of conditions such as periodontitis, peri-implantitis, Temporomandibular Joint Disorders (TMDs) and orofacial pain syndromes. Studies have demonstrated the efficacy of ESWT in reducing inflammation, promoting wound healing and improving clinical outcomes in these conditions. Furthermore, ESWT has shown promise in enhancing the outcomes of dental implant therapy by improving osseointegration and reducing implant failure rates. The non-invasive nature of ESWT, along with its minimal side effects and high patient acceptance, makes it a valuable adjunctive therapy in dental practice. ESWT thus represents a novel and effective approach in the management of various dental conditions. Further research is warranted to explore its full potential and establish standardized protocols for its use in dentistry.

Laser cladding is an emerging surface modification technology, and the cladding layer often suffers from defects such as cracks, inclusions and porosity. To address these challenges, ultrasonic vibration demonstrates effective mitigation of microstructural defects in clad layers. In this study, numerical simulation was used to investigate the transient law of different ultrasonic loading methods on the molten pool during laser cladding process. The study found that the introduction of ultrasonic vibration changed the flow rate of the molten metal and affected the Marangoni convection, which in turn changed the flow rate variation pattern inside the melt pool to some extent. The calculation results show that at 1000 ms, multi- directional ultrasonic vibration increases the peak flow rate of the molten pool from 0.23 m/s without vibration to over 0.36 m/s, significantly enhancing the fluidity of the molten pool. Compared with single-directional ultrasound, multi- directional ultrasound vibration breaks dendrites in growth through strong shock waves generated by cavitation effects, and combined with the vigorous stirring of acoustic flow effects, it achieves a more significant tissue refinement effect. The experimental results show that under the action of multi-directional ultrasound, the microstructure of the cladding layer undergoes a significant transformation from columnar crystals to equiaxed crystals. In addition, the average microhardness of the cladding layer increased from 535.3 HV without vibration to 624 HV, an increase of approximately 16.6%.

Pediatric nephrolithiasis continues to pose a substantial clinical challenge in pediatric urology because of its elevated recurrence rate and elevated morbidity with risk of end-stage renal failure. The management of pediatric nephrolithiasis involves dietary modification, pharmacological therapy, and urological intervention, with the choice of treatment guided by stone size, location, and composition. To evaluate the efficacy and safety of mini-percutaneous nephrolithotomy (mini-PCNL) and extracorporeal shock wave lithotripsy (SWL) for the management of renal stones measuring 1-2 cm in pediatrics. This prospective, randomized comparative research was conducted at the Department of Urology, Al-Azhar University Hospital, Assiut, Egypt, between December 2022 and November 2024. Sixty children with single renal stones were enrolled, with 30 undergoing SWL and 30 receiving mini-PCNL. Mini-PCNL achieved a significantly elevated stone-free rate (SFR, 93.33%) in contrast with SWL (33.33%) (p < 0.001). The SWL group also showed a higher rate of auxiliary approaches and retreatment. Overall complication rates were comparable. Mini-PCNL is more effective than SWL for managing renal stones measuring 10-20 mm in children aged 6 months to 6 years. It provides an elevated SFR and lowers the likelihood of retreatment and hospital readmission, with a comparable safety profile.

Universal behaviours of solid-state systems under static high pressures and temperatures are well known. With increasing pressure, the unit cell volume of materials decreases, and the materials frequently undergo high-pressure phases transitions. Acoustic shock waves can simultaneously offer dynamic thermal and high-pressure effects on materials. Herein, we investigate the corundum-type structures (α-Al2O3 and α-Fe2O3) of nanocrystalline particles under dynamic acoustic shocked conditions, and the observed structural results are compared with those obtained under static high-pressure and temperature conditions. According to the observed X-ray diffraction results, α-Al2O3 NPs' unit cell volume remains unchanged, whereas α-Fe2O3 NPs' unit cell volume increases under shocked conditions up to 150 shocks, and the Fe2O3 (R3̄c) to Fe3O4 (Fd3̄m) transition is observed under the 200-shocked condition. The structural stability results of α-Al2O3 and α-Fe2O3 NPs under acoustic shocked conditions are explained by their lattice thermal conductivity values based on a superheating approach. From the observed results, it is confirmed that acoustic shock waves create a new stage, which requires a collective approach for reinvestigating/rewriting the classical P-T phase diagrams, conventional phase transition paths and compression behaviour of materials/minerals because of their unique structural results.

A Rare Adverse Event of Pancreatic Extracorporeal Shock Wave Lithotripsy for Pancreatic Stones.

Theoretical studies of transonic accretion onto black holes reveal a wide range of possible solutions, broadly classified into smooth flows and flows featuring shocks. Accretion solutions that involve the formation of shocks are particularly intriguing, as they are expected to naturally produce observable variability features. However, despite their theoretical significance, time-dependent studies exploring the stability and evolution of such shocked solutions remain relatively scarce. To address this gap, we perform simulations of transonic accretion flows around a black hole in an ideal magnetohydrodynamic framework. Our simulations are initialized using boundary conditions derived from semi-analytical hydrodynamical models, allowing us to explore the stability of these flows under varying magnetic field strengths. Our results indicate that mildly magnetized flows in a uniform vertical magnetic field alter the accretion dynamics through magnetic pressure, with the resulting force imbalance driving oscillations in the shock front. Variations in the emitted luminosity arising from shock oscillations appear as quasi-periodic oscillations (QPOs), a characteristic feature commonly observed in accreting black holes. We find that the QPO frequency is determined by the radial position of the shock front: oscillations occurring closer to the black hole produce frequencies of tens of hertz, whereas shocks located farther out yield sub-hertz frequencies.

Background Chronic back pain is a common adult musculoskeletal disorder globally, causing lumbar dysfunction, sleep issues, and psychological anxiety. Yet current single-treatment plans have many limitations. Objective This study aimed to evaluate the efficacy of extracorporeal shock wave-based combined therapy for chronic back pain, analyze its impact on pain and lumbar function, and provide clinical evidence for multimodal treatment. Method This retrospective controlled study (September 2023–September 2025) enrolled 200 chronic low back pain (CLBP) patients from the Hospital, divided into two groups ( n = 100 each). The combined group received extracorporeal shock wave + core stability training + anti-inflammatory drugs, whereas the control group received exercise + anti-inflammatory drugs. The main indicators include Visual Analog Scale (VAS) (pain) and Oswestry Disability Index (ODI) (lumbar function), and the secondary indicators include Short Form 36 (SF-36) (quality of life), Berg Balance Scale (BBS) (posture control), Hospital Anxiety and Depression Scale (HADS) and Pittsburgh Sleep Quality Index (PSQI) (anxiety and sleep), serum IL-6, and TNF-α. Data were collected pretreatment and 4 and 12 weeks posttreatment, and a 12-week recurrence rate was recorded. Result No significant variations were observed in the baseline data of the two patient groups ( P &gt; 0.05). Following 4 and 12 weeks of treatment, two key differences emerged: First, the combined group had significantly lower values in VAS/ODI/HADS/PSQI scores and serum inflammatory factors (IL-6, TNF-α) than those of the control group ( P &lt; 0.05); second, the combined group's SF-36 and BBS scores were significantly higher than those of the control group ( P &lt; 0.05). Additionally, after 12 weeks of follow-up, the pain recurrence rate in the combined therapy group was significantly lower than that in the control group ( P &lt; 0.05). Conclusion The combination of extracorporeal shock wave therapy, core stability training, and anti-inflammatory drugs significantly alleviates pain, improves lumbar function/quality of life, reduces inflammation, and lowers long-term pain recurrence in CLBP treatment.

Summary This paper presents a novel thermodynamically consistent constitutive model for partially saturated porous rocks across a wide range of conditions. The material states generated behind the shock wave from an explosive source can vary significantly, ranging from crushed and melted rock near the source to a poroelastic medium in the far field. In the model, rock strength is determined by the effective pressure, which is calculated using two independent equations of state: one for the solid rock and another for the pore fluid. The model accounts for shock-induced liquefaction resulting from fluid pressure buildup in the pore spaces near the explosive source. Simultaneously, it describes the increase in wave propagation speed due to elastic pore contraction in both dry and partially saturated rocks. This model is applied to investigate how fluid saturation affects the amplitude and shape of the generated waves, as well as the residual stress surrounding the cavity formed by spherical explosions.

ABSTRACT This study investigates the shock initiation mechanisms of covered high explosive (HE) subjected to shaped charge jet (SCJ) penetration. With varying cover plate thicknesses and SCJ velocities, the impact and initiation processes exhibit complex dynamic behaviors. The initiation mechanisms for different jet velocities and cover plate configurations were analyzed. A theoretical model was established to describe the initiation process, accounting for the dynamic coupling between the precursor shock wave (PSW) and bow shock wave (BSW). The model’s predictive accuracy was validated against experimental data from prior studies. The influence of SCJ velocity and cover plate thickness on shock initiation was systematically examined. Results demonstrate that, for a given SCJ with a velocity of 7500 m/s, the initiation of covered HE is induced solely by the PSW when the cover plate thickness is below 20 mm. At moderate thicknesses (20–60 mm), initiation results from the dynamic coupling between the PSW and BSW. When the cover plate thickness exceeds 60 mm (up to 120 mm), where the PSW attenuates below the critical threshold, initiation occurs exclusively due to the BSW.

Background/Objectives: This systematic review and meta-analysis was designed to examine the efficacy of extracorporeal shock wave therapy (ESWT) and ultrasound therapy in the treatment of upper and lower limb tendinopathies. Methods: The protocol was registered in PROSPERO (CRD420251113976) and conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Electronic searches were performed in the PubMed, Embase, EBSCOhost, and Ovid MEDLINE databases up to August 2025, to identify randomized controlled trials (RCTs). Mean differences (MDs) and standardized mean differences (SMDs) were calculated with 95% confidence intervals (CIs). Heterogeneity was assessed using the I2 statistic, and a random-effects model was applied. Risk of bias was evaluated using the Risk of Bias (RoB 2) tool, and the certainty of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Results: Fourteen RCTs involving 639 patients with tendinopathies were included. All studies were characterized by a high risk of bias. Very low-certainty evidence suggested that ESWT as monotherapy may reduce pain at rest compared with ultrasound therapy in patients with lateral epicondylitis (MD = -1.51; 95% CI: -2.71 to -0.31; p = 0.01), although the effect was highly heterogeneous (I2 = 89.8%; p = 0.002). In patients with upper- and lower-limb tendinopathy, ESWT combined with pharmacotherapy resulted in significantly lower pain intensity compared with ultrasound therapy combined with pharmacotherapy (SMD = -0.6; 95% CI: -1.07 to -0.14; p = 0.01). No significant differences in PRTEE (Patient-Rated Tennis Elbow Evaluation) scores were observed between ESWT and ultrasound monotherapy in patients with lateral epicondylitis (MD = -1.06; 95% CI: -11.06 to 8.94; p = 0.83; I2 = 75.82%), or between ESWT combined with other conservative treatments and ultrasound combined with other conservative treatments (MD = 0.46; 95% CI: -10.22 to 11.15; p = 0.93; I2 = 0%). Conclusions: Very low-certainty evidence suggests that ESWT may be more effective than ultrasound therapy in reducing pain when used as monotherapy in lateral epicondylitis, despite substantial heterogeneity, and when combined with pharmacotherapy in upper- and lower-limb tendinopathies. In terms of function, ESWT appears to provide improvements comparable to those of ultrasound therapy, as assessed by PRTEE scores, in patients with lateral epicondylitis, both as monotherapy and when combined with other conservative treatments. However, significant methodological limitations substantially limit confidence in these findings.

The quasi-isentropic loading method based on multidimensional gradient structures plays a critical role in acquiring dynamic physical parameters and significantly enhances the service safety of materials. This study proposes a physics-guided machine learning (PGML) framework for high-fidelity prediction of quasi-isentropic loading waveforms under data-scarce conditions. The framework systematically integrates physical principles into the learning process through mathematically regulated inductive biases and deep feature engineering. By integrating shock propagation physics and an attention mechanism, this approach transforms sparse data into interpretable visual representations, achieving an R2 > 0.96 and 18.5 m/s MAE with only 528 samples while reducing shape alignment error by over 35% compared to baselines. The 4 × 4 augmentation strategy delivers a breakthrough performance in small-data prediction, achieving radically enhanced accuracy and training efficiency across impact velocities. A PGML framework, constrained by shock wave propagation behavior, coupled with SHAP analysis, reveals that the Hill coefficient (h) and curvature modulation parameter (K) dominate the loading path, providing interpretable insights into waveform modulation. The presented framework establishes a transformative, data-efficient paradigm for graded structure material design, substantially diminishing the dependency on resource-intensive simulations and experiments.

The development of effective medical expulsive therapy (MET) following extracorporeal shock wave lithotripsy (ESWL) for pediatric urolithiasis is crucial for enhancing stone fragment clearance. This study aimed to evaluate the efficacy and safety of alpha-1 adrenergic blockers (tamsulosin and silodosin) in children after ESWL. A prospective randomized comparative study was conducted involving 200 patients (aged 2-18 years) who underwent ESWL. Participants were allocated to a study group (n = 50, receiving α1-blockers: tamsulosin 0.2mg/day for ages 2-5, silodosin 4mg/day for ages > 5) or a control group (n = 150, receiving standard therapy). Primary endpoints were stone-free rate (SFR) and stone expulsion time. Secondary endpoints included pain dynamics (visual analog scale, VAS), analgesic requirements, and adverse events. Statistical analysis was performed using StatTech v.4.8.3. The odds of being stone-free were 2.11 times higher with α1-blocker therapy (OR = 2.11; 95% CI: 1.02-4.37). The median expulsion time was reduced from 7 [5-9] days in the control group to 5 [4-7] days in the study group (p = 0.010). ROC analysis identified a 6-day threshold for stone passage (sensitivity 63.6%, specificity 72.1%, AUC = 0.627; p = 0.010). Pain intensity was significantly lower in the study group on postoperative day 1 (3 [0-4] vs. 6 [5-8] points, p < 0.001), with reduced analgesic requirements (1 [0-2] vs. 2 [1-4] doses/day, p = 0.003). Adverse events were mild and infrequent (5 cases of nasal congestion, 2 of nausea). Adjunctive therapy with α1-blockers after ESWL in children with urolithiasis improves treatment efficacy, shortens stone expulsion time, reduces pain, and demonstrates a favorable safety profile. An optimal timeframe for efficacy assessment is 6 days post-ESWL.

Laser-driven annular shock waves as laboratory analogues of wCDM cosmologies and cosmological gravitational waves

To investigate the effects of 20 kHz low-frequency ultrasound irradiation-mediated microbubbles (USMB) combined with chemotherapy paclitaxel and cisplatin (PC) on ovarian cancer cells. In the in vitro research, ovarian cancer cell lines were divided into four groups: control, USMB, PC, and USMB+PC. The cell membrane structure was observed using scanning electron microscopy (SEM). A TUNEL assay was used to investigate cell apoptosis. In the in vivo study, USMB+PC was used to treat the ascites in the nude mice. The ascites volumes were calculated by magnetic resonance imaging. In the ex vivo research, ascites samples of clinical ovarian cancer patients were collected and focused with USMB+PC and observed by liquid-based cytology. SEM revealed cell wall defects in the USMB and USMB+PC, with pores ranging from 5 to 15 μm in diameter. The USMB+PC had the highest apoptosis rate, with statistical differences compared to the other three groups (all p<0.05). After USMB+PC treatment, the volume of ascites in the nude mice decreased (t=3.6, p=0.0228). In the USMB+PC, tumour cells in the ascites showed obvious degeneration and necrosis. The mechanism is that US irradiation causes MBs to rupture, generating shock waves, damaging tumor cell walls, forming pores (sonoporation), leading to more drugs entering cancer cells. The clinical significance of this technology is that it can increase the dosage of locally targeted tumor cells, reduce systemic chemotherapy use/or the clinical dosage of chemotherapy drugs, and decrease the toxic side effects on normal tissue cells. The limitation is that there are relatively few cases of patients with ex vivo ascites. Future research direction is US irradiation on ex vivo ascites of ovarian cancer patients with different histological types. US cavitation and chemotherapy inhibit ovarian cancer cells.