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Multi-physical Modeling and Adjusting for Ultrasonic Assisted Soft Abrasive Flow Processing

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 111-124页

作者： Yesha Ni Yunfeng Tan Dapeng Tan Key Lab of E&M Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310014China Collaborative Innovation Center of High-end Laser Manufacturing Equipment Zhejiang Province&Ministry of EducationHangzhou 310014China

The polishing efficiency of the soft abrasive flow(SAF)method is low,which is not in line with the concept of carbon emission reduction in industrial *** address the above issue,a two-phase fluid multi-physics modeling method for ultrasonic-assisted SAF processing is *** acoustics-fluid coupling mechanic model based on the realizable k-ε model and Helmholtz equation is built to analyze the cavitation *** results show that the pro-posed modeling and solution method oriented to ultrasonic-assisted SAF processing have better revealed the flow field evolution *** turbulence kinetic energy at different ultrasonic frequencies and amplitudes is *** results show that the ultrasonic vibration can induce a cavitation effect in the constrained flow chan-nel and promote the turbulence intensity and uniformity of the abrasive flow.A set of comparative polishing experiments with or without ultrasonic vibration are conducted to explore the performance of the proposed *** can be found that the ultrasonic-assisted SAF method can improve the machining efficiency and uniformity,to achieve the purpose of carbon emission *** relevant result can offer a helpful reference for the SAF method.

关键词： Soft abrasive flow Ultrasonic vibration cavitation effect Polishing efficiency Turbulent kinetic energy

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Ultrasound-mediated transdermal drug delivery of fluorescent nanoparticles and hyaluronic acid into porcine skin in vitro

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Chinese Physics B 2016年第12期25卷 98-105页

作者：王焕磊范鹏飞郭霞生屠娟马勇章东 Key Laboratory of Modern Acoustics (Nanjing University) Ministry of Education Nanjing 210093 China Department of Applied Engineering Zhejiang Business College Hangzhou 310053 China Institute of Traumatology and Orthopedics Nanjing University of Chinese Medicine Nanjing 210023 China

Transdermal drug delivery （TDD） can effectively bypass the first-pass effect. In this paper, ultrasound-facilitated TDD on fresh porcine skin was studied under various acoustic parameters, including frequency, amplitude, and exposure time. The delivery of yellow-green fluorescent nanoparticles and high molecular weight hyaluronic acid （HA） in the skin samples was observed by laser confocal microscopy and ultraviolet spectrometry, respectively. The results showed that, with the application of ultrasound exposures, the permeability of the skin to these markers （e.g., their penetration depth and concentration） could be raised above its passive diffusion permeability. Moreover, ultrasound-facilitated TDD was also tested with/without the presence of ultrasound contrast agents （UCAs）. When the ultrasound was applied without UCAs, low ultrasound frequency will give a better drug delivery effect than high frequency, but the penetration depth was less likely to exceed 200 p.m. However, with the help of the ultrasound-induced microbubble cavitation effect, both the penetration depth and concentration in the skin were significantly enhanced even more. The best ultrasound-facilitated TDD could be achieved with a drug penetration depth of over 600 p.m, and the penetration concentrations of fluorescent nanoparticles and HA increased up to about 4-5 folds. In order to get better understanding of ultrasound-facilitated TDD, scanning electron microscopy was used to examine the surface morphology of skin samples, which showed that the skin structure changed greatly under the treatment of ultrasound and UCA. The present work suggests that, for TDD applications （e.g., nanoparticle drug carriers, transdermal patches and cosmetics）, protocols and methods presented in this paper are potentially useful.

关键词： transdermal delivery of drugs ultrasound contrast agents pulsed ultrasound cavitation effect

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Microstructural evolution of ternary Ag33Cu-42Ge25 eutectic alloy inside ultrasonic field

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Progress in Natural Science:Materials International 2014年第5期24卷 642-648页

作者： Wei Zhai Xiaoyu Lu Bingbo Wei Department of Applied Physics Northwestern Polytechnical University

Ultrasonic field with a frequency of 20 k Hz is introduced into the solidification process of ternary Ag33Cu42Ge25 eutectic alloy from the sample bottom to its top. The ultrasound stimulates the nucleation of alloy melt and prevents its bulk undercooling. At low ultrasound power of 250 W,the primary ε2phase in the whole alloy sample grows into non-faceted equiaxed grains, which differs to its faceted morphology of long strip under static condition. The pseudobinary(Ag t ε2) eutectic transits from dendrite shape grain composed of rod type eutectic to equiaxed chrysanthemus shape formed by lamellar structure. By contrast, the ultrasound produces no obvious variation in the morphology of ternary(Ag t Ge t ε2) eutectic except a coarsening effect. When ultrasound power rises to 500 W, divorced ternary(Ag t Ge t ε2) eutectic forms at the sample bottom. However, in the upper part, the ultrasonic energy weakens, and it only brings about prominent refining effect to primary ε*** microstructural evolution mechanism is investigated on the cavitation, acoustic streaming and acoustic attenuation.

关键词： Dynamic solidification cavitation effect Ternary alloy Nucleation Eutectic growth

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Influencing factors on hydrodynamic lubrication failure of upstream pumping mechanical seal

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排灌机械工程学报 2018年第6期36卷 509-516页

作者： CHEN Huilong LI Xinwen WANG Bin WU Qiangbo REN Kunteng LI Tong ZHAO Binjuan School of Energy and Power Engineering Jiangsu University Zhenjiang Jiangsu 212013 China

Considering the effect of viscosity-temperature relationship and cavitation of micro-scale film,the influencing factors on hydrodynamic lubrication performance of upstream pumping mechanical seal were investigated based on the theory of hydrodynamic lubrication.N-S equation,energy equation,viscosity-temperature equation and vapor transport equation were solved with the finite volume method by using Fluent software,which was performed to analyze the influence of the viscosity-temperature and cavitation effect on hydrodynamic lubrication failure of the *** research demonstrates that it will lead to the significant difference of the temperature field by considering the coupling of temperature and *** the film thickness decreases and the rotating speed rises,cavitation regions and viscous friction heat increases,the opening force of the film is also ***,the growth rate is restricted to the cavitation regions and viscous friction heat,and the opening force begins to decline to a certain extent,and thereby being insufficient to open the surfaces of the seals and leading to the failure of automatic adjustment function and severe wear,lubrication failure *** comprehensive research on the influences of viscosity-temperature and cavitation effect on hydrodynamic lubrication performance,the theories of failure and design of upstream pumping mechanical seal are further developed.

关键词： mechanical seal hydrodynamic lubrication viscosity-temperature effect cavitation effect lubrication failure computational fluid dynamics

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CACA guidelines for ultrasound hyperthermia for oral and maxillofacial head and neck squamous cell carcinoma

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Holistic Integrative Oncology 2023年第1期2卷 101-107页

作者： Houyu Ju Jiawei Zheng Moyi Sun Zhangui Tang Daoke Yang Wei Ran Zhijun Sun Wei Shang Jian Meng Heming Wu Qing Xi Kai Yang Jun Wang Li Huang Jiaxuan Qiu Yunteng Wu Guoxin Ren Zhifei Dai Wei Guo Department of Oral Maxillofacial-Head and Neck Oncology Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Department of Oral and Maxillofacial Surgery School of StomatologyAir Force Military Medical UniversityXi’an 710032Shaanxi ProvinceChina Department of Oral and Maxillofacial Surgery Xiangya School of StomatologyCentral South UniversityChangsha 410013Hunan ProvinceChina Department of Radiotherapy the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Oral and Maxillofacial Surgery the First Affiliated Hospital of Sun Yat Sen UniversityGuangzhou 510080Guangdong ProvinceChina Department of Oral and Maxillofacial Headd Neck Oncology School and Hospital of StomatologyWuhan UniversityWuhan 430079China Department of Oral and Maxillofacial Surgery the Affiliated Hospital of Qingdao University Medical CollegeQingdao 266000Shandong ProvinceChina Department of Oral and Maxillofacial Surgery the Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221009Jiangsu ProvinceChina Department of Oral and Maxillofacial Surgery Stomatological Hospital Affiliated to Nanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina Department of Oral and Maxillofacial Surgery the First Medical Center of ChinesePLA General HospitalBeijingChina Department of Oral and Maxillofacial Surgery First Hospital Affiliated to Chongqing Medical UniversityChongqing 400016China Department of Head and Neck Surgery Gansu Cancer HospitalLanzhou 730050Gansu ProvinceChina Department of Oral and Maxillofacial Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhouChina Department of Stomatology The First Affiliated Hospital of Nanchang UniversityNanchangJiangxi 330006China Department of Biomedical Engineering College of Future TechnologyPeking UniversityBeijing 100871China

Most of the patients with oral and maxillofacial malignancy are in the middle and advanced stages at diagnosis and the incidence rate is increasing in recent *** alone is difficult to benefit the survival of patients with advanced oral and maxillofacial *** hyperthermia is a new and effective treatment for malignant tumor,which is developing rapidly in addition to conventional ***,at present,ultrasound hyperthermia has not been widely used in the treatment of oral and maxillofacial ***,formation of a guideline on ultrasound hyperthermia for oral and maxillofacial malignancy is mandatory,in order to promote and standardize the clinical practice of ultrasound hyperthermia in this field,and improve the long-term survival rate and quality of life of patients.

关键词： Oral and maxillofacial malignancy Ultrasound hyperthermia Combination therapy cavitation effect Guideline