Mowffaq Oreijah, Sami Ullah Khan, Muhammad Ijaz Khan, Sarah A. Alsalhi, Faris Alqurashi, Mohamed Kchaou
The aim of this study is to investigate the heat and mass transfer characteristics of Burgers nanofluid in the presence of thermo-diffusion effects. The analysis considers higher-order slip effects to study the transport phenomena. Additionally, the study examines the impact of thermal radiation and chemical reactions on the flow. Variable thermal conductivity assumptions are made for heat transfer analysis. The Cattaneo–Christov model, an extension of Fourier heat and mass theories, is employed for the analysis. Heat transfer evaluation is conducted using convective thermal constraints, and numerical computations are carried out using the Runge–Kutta method. The study visually represents the impact of flow parameters through graphical analysis. It is suggested that heat transfer can be significantly improved through the interaction of slip effects, and the concentration phenomenon is enhanced by the Soret number.
{"title":"Thermal analysis of generalized Cattaneo–Christov theories in Burgers nanofluid in the presence of thermo-diffusion effects and variable thermal conductivity","authors":"Mowffaq Oreijah, Sami Ullah Khan, Muhammad Ijaz Khan, Sarah A. Alsalhi, Faris Alqurashi, Mohamed Kchaou","doi":"10.1515/phys-2024-0042","DOIUrl":"https://doi.org/10.1515/phys-2024-0042","url":null,"abstract":"The aim of this study is to investigate the heat and mass transfer characteristics of Burgers nanofluid in the presence of thermo-diffusion effects. The analysis considers higher-order slip effects to study the transport phenomena. Additionally, the study examines the impact of thermal radiation and chemical reactions on the flow. Variable thermal conductivity assumptions are made for heat transfer analysis. The Cattaneo–Christov model, an extension of Fourier heat and mass theories, is employed for the analysis. Heat transfer evaluation is conducted using convective thermal constraints, and numerical computations are carried out using the Runge–Kutta method. The study visually represents the impact of flow parameters through graphical analysis. It is suggested that heat transfer can be significantly improved through the interaction of slip effects, and the concentration phenomenon is enhanced by the Soret number.","PeriodicalId":48710,"journal":{"name":"Open Physics","volume":"62 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141741575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work presents a numerical analysis by zero-dimensional global model of the influence of electron temperature and concentration on production of OH and NO for helium plasma jet propagating in the atmosphere of humid air. The calculations are done for the constant electron temperatures (1–4 eV) and concentrations (1010 cm−3 to 1014 cm−3). The mole fractions of air and water vapor vary from 100 to 10,000 ppm. The presented analysis reveals that at low electron temperature and H2O contents, the dissociative electron attachment to O2 dominates over attachment to H2O in production of OH. At higher amount, H2O modifies the high-energy tail of electron distribution function and increases rate coefficients for electron impact processes. Dissociative electron attachment to H2O dominates in the production of OH at 1 eV and remains important at higher energies when processes with O(1D), O(1S), O2(1∆) produce OH. Impact dissociation of H2O dominates over the dissociative attachment at 3 and 4 eV. NO comes mainly from air effluent in the plasma and O + NO2 at 100 ppm of H2O. Above 2 eV, the conversion process between OH and NO dominates in NO production at higher amount of H2O. Regarding dependencies on electron concentration, at low electron temperatures, electron distribution function is affected only at 1014 cm−3. But in the case of higher temperature, electron concentration and water vapor have negligible influence. The best agreement with measured data is obtained for electron concentration 1010 cm−3 and at temperature of 2 eV for OH and 1012 cm−3 and 3 eV for NO.
本研究通过零维全局模型，对在潮湿空气大气中传播的氦等离子体射流中电子温度和浓度对羟基和氮氧化物生成的影响进行了数值分析。计算是在电子温度（1-4 eV）和浓度（1010 cm-3 至 1014 cm-3）不变的情况下进行的。空气和水蒸气的摩尔分数从 100 到 10,000 ppm 不等。分析结果表明，在电子温度和 H2O 含量较低时，在产生 OH 的过程中，离解电子附着在 O2 上比附着在 H2O 上占优势。当电子温度和 H2O 含量较高时，H2O 会改变电子分布函数的高能量尾部，并增加电子撞击过程的速率系数。在 1 eV 时，电子与 H2O 的解离附着在产生 OH 的过程中占主导地位，在更高能量时，当与 O(1D)、O(1S)、O2(1∆) 的过程产生 OH 时，电子与 H2O 的解离附着仍然很重要。在 3 和 4 eV 时，H2O 的撞击解离比解离附着占优势。NO 主要来自等离子体中的空气流出物，在 H2O 为 100 ppm 时产生 O + NO2。在 2 eV 以上，当 H2O 含量较高时，OH 和 NO 之间的转化过程在 NO 生成中占主导地位。关于电子浓度的相关性，在低电子温度下，电子分布函数仅在 1014 cm-3 时受到影响。但在温度较高的情况下，电子浓度和水蒸气的影响可以忽略不计。在电子浓度为 1010 cm-3 和温度为 2 eV 时，OH 的电子分布函数与测量数据的一致性最好；在电子浓度为 1012 cm-3 和温度为 3 eV 时，NO 的电子分布函数与测量数据的一致性最好。
{"title":"Effect of electron temperature and concentration on production of hydroxyl radical and nitric oxide in atmospheric pressure low-temperature helium plasma jet: Swarm analysis and global model investigation","authors":"Željko Mladenović, Saša Gocić","doi":"10.1515/phys-2024-0055","DOIUrl":"https://doi.org/10.1515/phys-2024-0055","url":null,"abstract":"This work presents a numerical analysis by zero-dimensional global model of the influence of electron temperature and concentration on production of OH and NO for helium plasma jet propagating in the atmosphere of humid air. The calculations are done for the constant electron temperatures (1–4 eV) and concentrations (10<jats:sup>10</jats:sup> cm<jats:sup>−3</jats:sup> to 10<jats:sup>14</jats:sup> cm<jats:sup>−3</jats:sup>). The mole fractions of air and water vapor vary from 100 to 10,000 ppm. The presented analysis reveals that at low electron temperature and H<jats:sub>2</jats:sub>O contents, the dissociative electron attachment to O<jats:sub>2</jats:sub> dominates over attachment to H<jats:sub>2</jats:sub>O in production of OH. At higher amount, H<jats:sub>2</jats:sub>O modifies the high-energy tail of electron distribution function and increases rate coefficients for electron impact processes. Dissociative electron attachment to H<jats:sub>2</jats:sub>O dominates in the production of OH at 1 eV and remains important at higher energies when processes with O(<jats:sup>1</jats:sup>D), O(<jats:sup>1</jats:sup>S), O<jats:sub>2</jats:sub>(<jats:sup>1</jats:sup>∆) produce OH. Impact dissociation of H<jats:sub>2</jats:sub>O dominates over the dissociative attachment at 3 and 4 eV. NO comes mainly from air effluent in the plasma and O + NO<jats:sub>2</jats:sub> at 100 ppm of H<jats:sub>2</jats:sub>O. Above 2 eV, the conversion process between OH and NO dominates in NO production at higher amount of H<jats:sub>2</jats:sub>O. Regarding dependencies on electron concentration, at low electron temperatures, electron distribution function is affected only at 10<jats:sup>14</jats:sup> cm<jats:sup>−3</jats:sup>. But in the case of higher temperature, electron concentration and water vapor have negligible influence. The best agreement with measured data is obtained for electron concentration 10<jats:sup>10</jats:sup> cm<jats:sup>−3</jats:sup> and at temperature of 2 eV for OH and 10<jats:sup>12</jats:sup> cm<jats:sup>−3</jats:sup> and 3 eV for NO.","PeriodicalId":48710,"journal":{"name":"Open Physics","volume":"32 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141741573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article aims to provide a novel image paradigm for camouflaged object detection, i.e., RGB-D images. To promote the development of camouflaged object detection tasks based on RGB-D images, we construct an RGB-D camouflaged object detection dataset, dubbed CODD. This dataset is obtained by converting the existing salient object detection RGB-D datasets by image-to-image translation techniques, which is comparable to the current widely used camouflaged object detection dataset in terms of diversity and complexity. In particular, in order to obtain high-quality translated images, we design a selection strategy that takes into account the structural similarity between pre- and post-conversion images, the similarity between the appearance of objects and their surroundings, as well as the ambiguity of object boundaries. In addition, we extensively evaluate the CODD dataset using existing RGB-D-based salient object detection methods to validate the challenge and usability of the dataset. The CODD dataset will be available at: https://github.com/zcc0616/CODD-Dateset.git.
{"title":"A new benchmark for camouflaged object detection: RGB-D camouflaged object detection dataset","authors":"Dongdong Zhang, Chunping Wang, Qiang Fu","doi":"10.1515/phys-2024-0060","DOIUrl":"https://doi.org/10.1515/phys-2024-0060","url":null,"abstract":"This article aims to provide a novel image paradigm for camouflaged object detection, <jats:italic>i.e.</jats:italic>, RGB-D images. To promote the development of camouflaged object detection tasks based on RGB-D images, we construct an RGB-D camouflaged object detection dataset, dubbed CODD. This dataset is obtained by converting the existing salient object detection RGB-D datasets by image-to-image translation techniques, which is comparable to the current widely used camouflaged object detection dataset in terms of diversity and complexity. In particular, in order to obtain high-quality translated images, we design a selection strategy that takes into account the structural similarity between pre- and post-conversion images, the similarity between the appearance of objects and their surroundings, as well as the ambiguity of object boundaries. In addition, we extensively evaluate the CODD dataset using existing RGB-D-based salient object detection methods to validate the challenge and usability of the dataset. The CODD dataset will be available at: <jats:ext-link xmlns:xlink=\"http://www.w3.org/1999/xlink\" ext-link-type=\"uri\" xlink:href=\"https://github.com/zcc0616/CODD-Dateset.git\">https://github.com/zcc0616/CODD-Dateset.git</jats:ext-link>.","PeriodicalId":48710,"journal":{"name":"Open Physics","volume":"33 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141741574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In last decades, there have been drastic environmental transformations and mutations happening all around the world. Due to the continuous mass transfer process, for example, CO2{{rm{CO}}}_{2} mass transfer, which in this case, takes the form of greenhouse gas emissions, unusual and extreme kinds of phenomena have been occurring here and there, disturbing our ecosystems and causing damage and chaos on their paths. Reducing or stopping these gas emissions has become one of the major topics in our planet. We investigate the solvability of a mathematical model describing the mass transport process in nature and where additional perturbations parameters have been considered. Besides addressing the stability of the model, its convergence analysis is also given with the use of Crank–Nicholson numerical method, in order to assess its efficiency and perform some numerical simulations. The results obtained show that the model’s dynamic is characterized by many grouping (accumulation) zones, where mass (of CO2{{rm{CO}}}_{2}, for instance) accumulates in an increasing way. This result is important in controlling how CO2{{rm{CO}}}_{2} can be stored in this growingly perturbed environment that surrounds us.
在过去的几十年里，世界各地都发生了剧烈的环境变化和突变。由于持续的质量传递过程，例如 CO 2 {{rm{CO}}}_{2} 质量传递，在这种情况下，以温室气体排放的形式，不寻常和极端的现象时有发生，扰乱了我们的生态系统，造成了破坏和混乱。减少或阻止这些气体的排放已成为我们这个星球上的主要话题之一。我们研究了一个描述自然界质量传输过程的数学模型的可解性，其中考虑了额外的扰动参数。除了研究模型的稳定性，我们还利用 Crank-Nicholson 数值方法对模型的收敛性进行了分析，以评估其效率，并进行了一些数值模拟。研究结果表明，该模型的动态特征是有许多分组（累积）区，在这些分组区中，（例如 CO 2 {{rm{CO}}}_{2} 的）质量以递增的方式累积。这一结果对于控制 CO 2 {{rm{CO}}{2} 如何储存在我们周围这个日益受到干扰的环境中非常重要。
{"title":"Accumulation process in the environment for a generalized mass transport system","authors":"Emile F. Doungmo Goufo, Amos Kubeka","doi":"10.1515/phys-2024-0054","DOIUrl":"https://doi.org/10.1515/phys-2024-0054","url":null,"abstract":"In last decades, there have been drastic environmental transformations and mutations happening all around the world. Due to the continuous mass transfer process, for example, <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" xlink:href=\"graphic/j_phys-2024-0054_eq_001.png\"/> <m:math xmlns:m=\"http://www.w3.org/1998/Math/MathML\"> <m:msub> <m:mrow> <m:mi mathvariant=\"normal\">CO</m:mi> </m:mrow> <m:mrow> <m:mn>2</m:mn> </m:mrow> </m:msub> </m:math> <jats:tex-math>{{rm{CO}}}_{2}</jats:tex-math> </jats:alternatives> </jats:inline-formula> mass transfer, which in this case, takes the form of greenhouse gas emissions, unusual and extreme kinds of phenomena have been occurring here and there, disturbing our ecosystems and causing damage and chaos on their paths. Reducing or stopping these gas emissions has become one of the major topics in our planet. We investigate the solvability of a mathematical model describing the mass transport process in nature and where additional perturbations parameters have been considered. Besides addressing the stability of the model, its convergence analysis is also given with the use of Crank–Nicholson numerical method, in order to assess its efficiency and perform some numerical simulations. The results obtained show that the model’s dynamic is characterized by many grouping (accumulation) zones, where mass (of <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" xlink:href=\"graphic/j_phys-2024-0054_eq_002.png\"/> <m:math xmlns:m=\"http://www.w3.org/1998/Math/MathML\"> <m:msub> <m:mrow> <m:mi mathvariant=\"normal\">CO</m:mi> </m:mrow> <m:mrow> <m:mn>2</m:mn> </m:mrow> </m:msub> </m:math> <jats:tex-math>{{rm{CO}}}_{2}</jats:tex-math> </jats:alternatives> </jats:inline-formula>, for instance) accumulates in an increasing way. This result is important in controlling how <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" xlink:href=\"graphic/j_phys-2024-0054_eq_003.png\"/> <m:math xmlns:m=\"http://www.w3.org/1998/Math/MathML\"> <m:msub> <m:mrow> <m:mi mathvariant=\"normal\">CO</m:mi> </m:mrow> <m:mrow> <m:mn>2</m:mn> </m:mrow> </m:msub> </m:math> <jats:tex-math>{{rm{CO}}}_{2}</jats:tex-math> </jats:alternatives> </jats:inline-formula> can be stored in this growingly perturbed environment that surrounds us.","PeriodicalId":48710,"journal":{"name":"Open Physics","volume":"12 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141741576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The coherent manipulation and control of bright and dark solitons through sodium atomic medium have been investigated in this manuscript. Dark soliton is reported for reflection and bright soliton is reported for transmission pulses with variation in position and driving field parameters through sodium atomic medium. Further the transmission pulse is periodic dark and bright solitonic behaviors and reflection pulse is periodic bright solitonic behavior with variation in the incident angle and Rabi frequency of the control field. Elliptical dark and bright solitons as well as breather types solitons are also investigated for reflection and transmission pulses. The dark soliton in reflection is due to slow light propagation and bright soliton is obtained due to fast light propagation of transmission through the medium. The modified results of the dark and bright solitons are useful for telecommunication and ultra-fast signal routing system.
{"title":"Coherent manipulation of bright and dark solitons of reflection and transmission pulses through sodium atomic medium","authors":"Thabet Abdeljawad, Asma Al-Jaser, Bahaaeldin Abdalla, Kamal Shah, Manel Hleil, Manar Alqudah","doi":"10.1515/phys-2024-0058","DOIUrl":"https://doi.org/10.1515/phys-2024-0058","url":null,"abstract":"The coherent manipulation and control of bright and dark solitons through sodium atomic medium have been investigated in this manuscript. Dark soliton is reported for reflection and bright soliton is reported for transmission pulses with variation in position and driving field parameters through sodium atomic medium. Further the transmission pulse is periodic dark and bright solitonic behaviors and reflection pulse is periodic bright solitonic behavior with variation in the incident angle and Rabi frequency of the control field. Elliptical dark and bright solitons as well as breather types solitons are also investigated for reflection and transmission pulses. The dark soliton in reflection is due to slow light propagation and bright soliton is obtained due to fast light propagation of transmission through the medium. The modified results of the dark and bright solitons are useful for telecommunication and ultra-fast signal routing system.","PeriodicalId":48710,"journal":{"name":"Open Physics","volume":"46 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141741577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lakshmi Sireesha Challa, Ravi Ragoju, Sathishkumar Veerappampalayam Easwaramoorthy, Jaehyuk Cho
The present study investigates the thermal convection of a power-law fluid in a horizontal porous layer that is heated from below. The study of flow in a porous medium is important because of its applications in various fields such as agriculture, geothermal sciences, and engineering. Linear instability analysis is performed using the normal mode method to solve the governing equations after non-dimensionalization. The bvp4c routine in MATLAB R2020a has been used to solve the raised problem for linear instability. The impact of gravity parameter, Peclet number, and power-law index on linear instability has been investigated. Linear and quadratic variations of gravity field are considered. From the results, it is evident that the critical Rayleigh number exhibits a non-monotonic relationship with the Peclet number. Increasing the gravity variation parameter leads to a more stable system, particularly in the case of linear gravity variation.
{"title":"Linear instability of the vertical throughflow in a porous layer saturated by a power-law fluid with variable gravity effect","authors":"Lakshmi Sireesha Challa, Ravi Ragoju, Sathishkumar Veerappampalayam Easwaramoorthy, Jaehyuk Cho","doi":"10.1515/phys-2024-0049","DOIUrl":"https://doi.org/10.1515/phys-2024-0049","url":null,"abstract":"The present study investigates the thermal convection of a power-law fluid in a horizontal porous layer that is heated from below. The study of flow in a porous medium is important because of its applications in various fields such as agriculture, geothermal sciences, and engineering. Linear instability analysis is performed using the normal mode method to solve the governing equations after non-dimensionalization. The bvp4c routine in MATLAB R2020a has been used to solve the raised problem for linear instability. The impact of gravity parameter, Peclet number, and power-law index on linear instability has been investigated. Linear and quadratic variations of gravity field are considered. From the results, it is evident that the critical Rayleigh number exhibits a non-monotonic relationship with the Peclet number. Increasing the gravity variation parameter leads to a more stable system, particularly in the case of linear gravity variation.","PeriodicalId":48710,"journal":{"name":"Open Physics","volume":"62 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141741578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muthu Rajarathinam, Muhammad Ijaz Khan, Barno Sayfutdinovna Abdullaeva, Tehseen Abbas, Fuad A. Awwad, Emad A. A. Ismail
This study examines the influence of wall velocity ratio on mixed convective heat transport in a permeable cavity containing an isothermal solid block at its center. The analysis considers the characteristics of various flow variables, i.e., Darcy number, wall velocity ratio, Richardson number, and volume fraction of suspended nanoparticles, on heat transport and material flow characteristics. The principal equations are solved implementing the semi-implicit method for pressure linked equations algorithm, and the outcomes are compared with existing literature. The study shows that rising estimations of Darcy number, velocity ratio, Richardson number, and nanoparticles volume fraction lead to improved heat transfer rates. For example, at high Richardson number (100) and solid volume fraction (0.05), increasing the velocity ratio from 0.5 to 1.5 results in a 6% (5%) upsurge in heat transport rate. Conversely, at smaller Richardson number (0.01), the heat transport rate upsurges by 29% (28%). Similarly, at high Darcy numbers and low wall velocity ratios, a 3% (4%) escalate in heat transport rate is observed with an increase in nanoparticles concentration from 0 to 0.05, while a 9% (8%) increase in thermal performance is achieved at low Darcy numbers. The study emphasizes the importance of optimizing the combination of nanoparticles volume fraction, Darcy number, velocity ratio, and Richardson number to maximize thermal performance in the porous cavity.
{"title":"Optimizing heat transport in a permeable cavity with an isothermal solid block: Influence of nanoparticles volume fraction and wall velocity ratio","authors":"Muthu Rajarathinam, Muhammad Ijaz Khan, Barno Sayfutdinovna Abdullaeva, Tehseen Abbas, Fuad A. Awwad, Emad A. A. Ismail","doi":"10.1515/phys-2024-0003","DOIUrl":"https://doi.org/10.1515/phys-2024-0003","url":null,"abstract":"This study examines the influence of wall velocity ratio on mixed convective heat transport in a permeable cavity containing an isothermal solid block at its center. The analysis considers the characteristics of various flow variables, <jats:italic>i.e</jats:italic>., Darcy number, wall velocity ratio, Richardson number, and volume fraction of suspended nanoparticles, on heat transport and material flow characteristics. The principal equations are solved implementing the semi-implicit method for pressure linked equations algorithm, and the outcomes are compared with existing literature. The study shows that rising estimations of Darcy number, velocity ratio, Richardson number, and nanoparticles volume fraction lead to improved heat transfer rates. For example, at high Richardson number (100) and solid volume fraction (0.05), increasing the velocity ratio from 0.5 to 1.5 results in a 6% (5%) upsurge in heat transport rate. Conversely, at smaller Richardson number (0.01), the heat transport rate upsurges by 29% (28%). Similarly, at high Darcy numbers and low wall velocity ratios, a 3% (4%) escalate in heat transport rate is observed with an increase in nanoparticles concentration from 0 to 0.05, while a 9% (8%) increase in thermal performance is achieved at low Darcy numbers. The study emphasizes the importance of optimizing the combination of nanoparticles volume fraction, Darcy number, velocity ratio, and Richardson number to maximize thermal performance in the porous cavity.","PeriodicalId":48710,"journal":{"name":"Open Physics","volume":"150 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141570414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hydrodynamic cavitation is widely used in many fields such as water treatment, impact rock breaking, and food preparation. The performance of hydrodynamic cavitation is closely related to its internal flow field. In the present study, cavitation flow field was analyzed by computational fluid dynamics in the reactor. The cavitation performance of the rotor is evaluated under different operating conditions. The time frequency distribution of pressure pulsation is studied. The pressure increases at the connection point between the local low-pressure area and the mainstream low-pressure area. Cavitation bubbles collapsed at the tail end of the cavity to form a local void area. The blade frequency amplitude of pressure pulsation shows the significant periodic change. The blade frequency amplitude decreases along the flow direction. The effect of the fluid outlet led to the increase in the second-order harmonic frequency amplitude. The research results could provide theoretical support for the research of cavitation mechanism of cavitation equipment.
{"title":"Study on cavitation and pulsation characteristics of a novel rotor-radial groove hydrodynamic cavitation reactor","authors":"Deman Zhang, Peng Deng, Ruijie Hou, Yongxing Song, Jingting Liu, Weibin Zhang","doi":"10.1515/phys-2024-0030","DOIUrl":"https://doi.org/10.1515/phys-2024-0030","url":null,"abstract":"Hydrodynamic cavitation is widely used in many fields such as water treatment, impact rock breaking, and food preparation. The performance of hydrodynamic cavitation is closely related to its internal flow field. In the present study, cavitation flow field was analyzed by computational fluid dynamics in the reactor. The cavitation performance of the rotor is evaluated under different operating conditions. The time frequency distribution of pressure pulsation is studied. The pressure increases at the connection point between the local low-pressure area and the mainstream low-pressure area. Cavitation bubbles collapsed at the tail end of the cavity to form a local void area. The blade frequency amplitude of pressure pulsation shows the significant periodic change. The blade frequency amplitude decreases along the flow direction. The effect of the fluid outlet led to the increase in the second-order harmonic frequency amplitude. The research results could provide theoretical support for the research of cavitation mechanism of cavitation equipment.","PeriodicalId":48710,"journal":{"name":"Open Physics","volume":"27 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141524512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muhammad Farooq, Rashid Nawaz, Alamgeer Khan, Bakri Adam Younis, Fathi Mohammed DawAlbait, Gamal M. Ismail
In this article, the plane Poiseuille flow of couple stress fluid of Vogel’s model between two parallel plates under the influence of non-isothermal effects have been investigated using Optimal homotopy asymptotic method (OHAM) and New iterative method (NIM). The governing continuity and momentum equations are transformed to ordinary differential equations and the coupled system of differential equations is then explored using the said methods. The expressions for velocity profile, temperature distribution, average velocity, volume flux, and shear stress have been obtained employing the said methods. Various essential flow properties have been presented and discussed. The results acquired via these techniques are in the form of infinite series; thus, the results can be effortlessly calculated. Comparison of both techniques are illustrated with the help of different tables and graphs and found both methods to be in a good agreement. Consequently, it will be more appealing for the investigators to apply the proposed methods to diverse problems arising in fluid dynamics.
{"title":"Comparative study of couple stress fluid flow using OHAM and NIM","authors":"Muhammad Farooq, Rashid Nawaz, Alamgeer Khan, Bakri Adam Younis, Fathi Mohammed DawAlbait, Gamal M. Ismail","doi":"10.1515/phys-2024-0038","DOIUrl":"https://doi.org/10.1515/phys-2024-0038","url":null,"abstract":"In this article, the plane Poiseuille flow of couple stress fluid of Vogel’s model between two parallel plates under the influence of non-isothermal effects have been investigated using Optimal homotopy asymptotic method (OHAM) and New iterative method (NIM). The governing continuity and momentum equations are transformed to ordinary differential equations and the coupled system of differential equations is then explored using the said methods. The expressions for velocity profile, temperature distribution, average velocity, volume flux, and shear stress have been obtained employing the said methods. Various essential flow properties have been presented and discussed. The results acquired <jats:italic>via</jats:italic> these techniques are in the form of infinite series; thus, the results can be effortlessly calculated. Comparison of both techniques are illustrated with the help of different tables and graphs and found both methods to be in a good agreement. Consequently, it will be more appealing for the investigators to apply the proposed methods to diverse problems arising in fluid dynamics.","PeriodicalId":48710,"journal":{"name":"Open Physics","volume":"44 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141510179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study calls attention to the current state of the probability (P) domain which presents weak points at the mathematical level and more significant flaws at the application level. Popper noticed how fundamental issues raised in quantum mechanics (QM) directly derive from unresolved probabilistic questions. Endless philosophical debates create more problems than solutions, so the author of this research suggests going directly to the root of the issues and searching for the probability theory which formalizes the multifold nature of P. This study offers a brief overview of the structural theory of probability, recently published in a book, and applies it to QM in order to show its completeness. The whole probability-based interpretation of QM goes beyond the limits of a paper and these pages condense a few aspects of this theoretical scheme. The double slit experiment is used to corroborate the theorems presented here.
这项研究呼吁人们关注概率（P）领域的现状，即在数学层面存在薄弱点，而在应用层面则存在更多重大缺陷。波普尔注意到量子力学（QM）中提出的基本问题是如何直接源于未解决的概率问题的。无休止的哲学争论造成的问题多于解决办法，因此，本研究的作者建议直接从问题的根源入手，寻找将 P 的多面性形式化的概率论。本研究简要概述了最近出版的概率论结构理论一书，并将其应用于量子力学，以显示其完整性。对 QM 的整个基于概率的解释超出了一篇论文的限制，这些篇幅浓缩了这一理论方案的几个方面。双缝实验被用来证实这里提出的定理。
{"title":"A short report on a probability-based interpretation of quantum mechanics","authors":"Paolo Rocchi","doi":"10.1515/phys-2024-0047","DOIUrl":"https://doi.org/10.1515/phys-2024-0047","url":null,"abstract":"This study calls attention to the current state of the probability (<jats:italic>P</jats:italic>) domain which presents weak points at the mathematical level and more significant flaws at the application level. Popper noticed how fundamental issues raised in quantum mechanics (QM) directly derive from unresolved probabilistic questions. Endless philosophical debates create more problems than solutions, so the author of this research suggests going directly to the root of the issues and searching for the probability theory which formalizes the multifold nature of <jats:italic>P</jats:italic>. This study offers a brief overview of the <jats:italic>structural theory of probability</jats:italic>, recently published in a book, and applies it to QM in order to show its completeness. The whole <jats:italic>probability-based interpretation of QM</jats:italic> goes beyond the limits of a paper and these pages condense a few aspects of this theoretical scheme. The double slit experiment is used to corroborate the theorems presented here.","PeriodicalId":48710,"journal":{"name":"Open Physics","volume":"2013 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141530108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：