Pub Date : 2024-09-01DOI: 10.1016/j.jppr.2024.07.001
Qiancheng Ouyang , Zaiyun Zhang , Qiong Wang , Wenjing Ling , Pengcheng Zou , Xinping Li
In this paper, by using the bifurcation theory for dynamical system, we construct traveling wave solutions of a high-order nonlinear Schrödinger equation with a quintic nonlinearity. Firstly, based on wave variables, the equation is transformed into an ordinary differential equation. Then, under the parameter conditions, we obtain the Hamiltonian system and phase portraits. Finally, traveling wave solutions which contains solitary, periodic and kink wave solutions are constructed by integrating along the homoclinic or heteroclinic orbits. In addition, by choosing appropriate values to parameters, different types of structures of solutions can be displayed graphically. Moreover, the computational work and it's figures show that this technique is influential and efficient.
{"title":"Solitary, periodic, kink wave solutions of a perturbed high-order nonlinear Schrödinger equation via bifurcation theory","authors":"Qiancheng Ouyang , Zaiyun Zhang , Qiong Wang , Wenjing Ling , Pengcheng Zou , Xinping Li","doi":"10.1016/j.jppr.2024.07.001","DOIUrl":"10.1016/j.jppr.2024.07.001","url":null,"abstract":"<div><div>In this paper, by using the bifurcation theory for dynamical system, we construct traveling wave solutions of a high-order nonlinear Schrödinger equation with a quintic nonlinearity. Firstly, based on wave variables, the equation is transformed into an ordinary differential equation. Then, under the parameter conditions, we obtain the Hamiltonian system and phase portraits. Finally, traveling wave solutions which contains solitary, periodic and kink wave solutions are constructed by integrating along the homoclinic or heteroclinic orbits. In addition, by choosing appropriate values to parameters, different types of structures of solutions can be displayed graphically. Moreover, the computational work and it's figures show that this technique is influential and efficient.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 3","pages":"Pages 433-444"},"PeriodicalIF":5.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141843871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-01DOI: 10.1016/j.jppr.2024.07.002
Snehal Patel , Harshad R. Patel
This study examines the effect of heat production and radiation absorption on the magnetohydrodynamic Casson fluid flow at the stagnation point in a porous medium. We convert the group of fluid flow equations, which are non-linear partial differential equations with suitable boundary constraints, into a set of non-linear ordinary differential equations using similarity transformations. The homotopy analysis method (HAM) solves the converted system of ordinary differential equations. We draw graphs for numerous values of non-dimensional parameters and tables of surface drag force, rates of heat transfer, and mass transfer to analyze the relationship between velocity field, temperature field, concentration field, and other essential parameters involved in the study. We have proven that the Dufour number, radiation parameter, and heat generation parameter elevate the fluid temperature, whereas the magnetic parameter lowers it. The Casson fluid parameter, buoyancy force parameter, and mixed convection parameter all promote fluid movement throughout the flow field. The presented tabular data allows us to see the trend of heat and mass transfer rates, as well as drag force rates, against important parameters, enhancing our understanding of these rates.
{"title":"Magnetohydrodynamics bio-convection flow at Casson fluid stagnation point in porous medium: Cross-diffusion effect and heat production","authors":"Snehal Patel , Harshad R. Patel","doi":"10.1016/j.jppr.2024.07.002","DOIUrl":"10.1016/j.jppr.2024.07.002","url":null,"abstract":"<div><div>This study examines the effect of heat production and radiation absorption on the magnetohydrodynamic Casson fluid flow at the stagnation point in a porous medium. We convert the group of fluid flow equations, which are non-linear partial differential equations with suitable boundary constraints, into a set of non-linear ordinary differential equations using similarity transformations. The homotopy analysis method (HAM) solves the converted system of ordinary differential equations. We draw graphs for numerous values of non-dimensional parameters and tables of surface drag force, rates of heat transfer, and mass transfer to analyze the relationship between velocity field, temperature field, concentration field, and other essential parameters involved in the study. We have proven that the Dufour number, radiation parameter, and heat generation parameter elevate the fluid temperature, whereas the magnetic parameter lowers it. The Casson fluid parameter, buoyancy force parameter, and mixed convection parameter all promote fluid movement throughout the flow field. The presented tabular data allows us to see the trend of heat and mass transfer rates, as well as drag force rates, against important parameters, enhancing our understanding of these rates.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 3","pages":"Pages 445-457"},"PeriodicalIF":5.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142247296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-01DOI: 10.1016/j.jppr.2024.08.004
Cheng-Wei Fei , Chen Li , Jia-Yi Lin , Yao-Jia Han , Yat-Sze Choy , Chuan-Hai Chen
Structural modularization, lightweight and functional integration are the urgent development directions for next generation high-performance aeroengines. Heat concentration during aeroengine operation would lead to local high temperature, which tremendously negative impacts on aeroengine structural life and performance. Therefore, the design and optimization of radiator structures are significant for the efficiency and reliability of aeroengine. The structural geometry design and layout optimization of radiators is promising to improve the heat dissipation efficiency and reduce aerodynamic loss. The purpose of this study is to investigate the state of the art and perspectives of aeroengine radiator structural design by a comprehensive literature review. The main contents involve the review on the structural design and layout optimization technologies of radiator structures, the analyses of the structural features, design theory and methods of existed radiator structures, the induction of the theory and method of different radiators structural optimization design, and the discussion on the application perspectives of advanced structures in aeroengine radiators, the report on the current challenges and development directions of the design of radiator structures, including smart materials, lattice structures, variable structures, advanced optimization theories and methods, heat dissipation methods and so forth. The efforts of this study are promising to support the high-performance and lightweight design of aeroengine structures besides radiators, and thermal management system.
{"title":"Structural design of aeroengine radiators: State of the art and perspectives","authors":"Cheng-Wei Fei , Chen Li , Jia-Yi Lin , Yao-Jia Han , Yat-Sze Choy , Chuan-Hai Chen","doi":"10.1016/j.jppr.2024.08.004","DOIUrl":"10.1016/j.jppr.2024.08.004","url":null,"abstract":"<div><div>Structural modularization, lightweight and functional integration are the urgent development directions for next generation high-performance aeroengines. Heat concentration during aeroengine operation would lead to local high temperature, which tremendously negative impacts on aeroengine structural life and performance. Therefore, the design and optimization of radiator structures are significant for the efficiency and reliability of aeroengine. The structural geometry design and layout optimization of radiators is promising to improve the heat dissipation efficiency and reduce aerodynamic loss. The purpose of this study is to investigate the state of the art and perspectives of aeroengine radiator structural design by a comprehensive literature review. The main contents involve the review on the structural design and layout optimization technologies of radiator structures, the analyses of the structural features, design theory and methods of existed radiator structures, the induction of the theory and method of different radiators structural optimization design, and the discussion on the application perspectives of advanced structures in aeroengine radiators, the report on the current challenges and development directions of the design of radiator structures, including smart materials, lattice structures, variable structures, advanced optimization theories and methods, heat dissipation methods and so forth. The efforts of this study are promising to support the high-performance and lightweight design of aeroengine structures besides radiators, and thermal management system.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 3","pages":"Pages 319-334"},"PeriodicalIF":5.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142247294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-01DOI: 10.1016/j.jppr.2024.08.001
M. Priya, P. Bala Anki Reddy
This study employs numerical and statistical approaches to investigate the entropy optimization of steady Casson nanofluid flow over three different geometries subject to boundary conditions induced by convective flow. Multiple linear regression is employed to statistically examine. The present model incorporates several novel elements, such as Arrhenius activation energy, Brownian motion, the Cattaneo-Christov dual flux, thermophoresis, thermal radiation, and so on. Moreover, a comparison is presented between Newtonian and non-Newtonian fluids. By applying the proper similarity transformations, ordinary differential equations (ODEs) are obtained by converting foundational partial differential equations (PDEs). The Runge-Kutta fourth-order method is utilised to solve the obtained ODEs along with the shooting technique. The outcomes are visually depicted via tables and graphs. The velocity drops with increasing Grashof number, and the magnetic field becomes progressively more forceful as the suction parameter increases. The temperature gets reduced with the increase of the suction parameter, solute Grashof number increases with the magnetic field, thermophoresis, and radiation parameters. The entropy is observed to rise with the increase of the effective parameters (magnetic field, Brinkmann number and radiation). The MAD (mean absolute deviation), MSE (mean squared error), and RMSE (root mean square error) values are approaching zero, indicating that the derived outcomes are highly accurate. A lower MAPE (mean absolute percentage error) suggests that the model has a higher level of precision. Therefore, the outcomes of the present model are more precise and reliable. This study has various potential applications such as power plant heat exchangers, material processing industries, and solar thermal energy systems.
{"title":"Entropy optimization on Casson nanofluid flow with radiation and Arrhenius activation energy over different geometries: A numerical and statistical approach","authors":"M. Priya, P. Bala Anki Reddy","doi":"10.1016/j.jppr.2024.08.001","DOIUrl":"10.1016/j.jppr.2024.08.001","url":null,"abstract":"<div><div>This study employs numerical and statistical approaches to investigate the entropy optimization of steady Casson nanofluid flow over three different geometries subject to boundary conditions induced by convective flow. Multiple linear regression is employed to statistically examine. The present model incorporates several novel elements, such as Arrhenius activation energy, Brownian motion, the Cattaneo-Christov dual flux, thermophoresis, thermal radiation, and so on. Moreover, a comparison is presented between Newtonian and non-Newtonian fluids. By applying the proper similarity transformations, ordinary differential equations (ODEs) are obtained by converting foundational partial differential equations (PDEs). The Runge-Kutta fourth-order method is utilised to solve the obtained ODEs along with the shooting technique. The outcomes are visually depicted via tables and graphs. The velocity drops with increasing Grashof number, and the magnetic field becomes progressively more forceful as the suction parameter increases. The temperature gets reduced with the increase of the suction parameter, solute Grashof number increases with the magnetic field, thermophoresis, and radiation parameters. The entropy is observed to rise with the increase of the effective parameters (magnetic field, Brinkmann number and radiation). The MAD (mean absolute deviation), MSE (mean squared error), and RMSE (root mean square error) values are approaching zero, indicating that the derived outcomes are highly accurate. A lower MAPE (mean absolute percentage error) suggests that the model has a higher level of precision. Therefore, the outcomes of the present model are more precise and reliable. This study has various potential applications such as power plant heat exchangers, material processing industries, and solar thermal energy systems.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 3","pages":"Pages 375-393"},"PeriodicalIF":5.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142247295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-01DOI: 10.1016/j.jppr.2024.05.003
Sweeping jet actuator (SJA) has been widely applied for active flow control in open flows. In this paper, the SJA character in compressor cascade and its performance for separation control in inner flows are discussed. Time-averaged and transient flow field measurement, together with visualization methods are utilized. It is found that endwall effects are important for both SJA behaviors and SJA performance for separation control in compressor cascades. There is a maximum of 12.7% total pressure loss reduction with SJA placed near the separation position, close to the endwall and under appropriate flowrate. The characteristic frequencies in the flow field contribute to the capture of influence regions of vortices and excitation jets. Two concentrated shedding vortices and SJA jets impact region helped to judge that SJA energizes low momentum fluids in a large region and matches the high loss core well. To be concrete, the flow separation control mechanism of SJA lies on the interruption of the blade suction surface boundary layer development and the restriction of the lifting of the boundary layer from endwall towards blade suction surface.
{"title":"Experimental study of corner separation and unsteady characteristics in linear compressor cascades with and without sweeping jet actuator","authors":"","doi":"10.1016/j.jppr.2024.05.003","DOIUrl":"10.1016/j.jppr.2024.05.003","url":null,"abstract":"<div><div>Sweeping jet actuator (SJA) has been widely applied for active flow control in open flows. In this paper, the SJA character in compressor cascade and its performance for separation control in inner flows are discussed. Time-averaged and transient flow field measurement, together with visualization methods are utilized. It is found that endwall effects are important for both SJA behaviors and SJA performance for separation control in compressor cascades. There is a maximum of 12.7% total pressure loss reduction with SJA placed near the separation position, close to the endwall and under appropriate flowrate. The characteristic frequencies in the flow field contribute to the capture of influence regions of vortices and excitation jets. Two concentrated shedding vortices and SJA jets impact region helped to judge that SJA energizes low momentum fluids in a large region and matches the high loss core well. To be concrete, the flow separation control mechanism of SJA lies on the interruption of the blade suction surface boundary layer development and the restriction of the lifting of the boundary layer from endwall towards blade suction surface.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 3","pages":"Pages 360-374"},"PeriodicalIF":5.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141413334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-01DOI: 10.1016/j.jppr.2024.09.001
Anam Ali, Khalid Saifullah Syed
This present study is part of the design improvement process of a specified high torque low-speed engine. This work aims at carrying out an in-depth analysis of in-cylinder combustion, mesh sensitivity, and engine performance at supercharge conditions to provide a foundation for the design improvement process of the given engine. The computational fluid dynamic (CFD) simulations are carried out on a 3D sector from to crank angle (CA) by employing appropriate models to represent the different physical and chemical processes and using the finite volume method for solving the governing differential equations. An extensive investigation has been carried out for the choice of base mesh size and the number of local and temporal refinements to capture the phenomena happening in the combustion chamber at diverse temporal and local scales. The present results have been validated against available literature experimental and simulation results. Primary field variables and the well-known four phases of combustion have been studied for gaining in-depth insight into these phenomena. Cylinder average pressure, mean temperature, heat release rate (HRR), integrated heat release rate (IHRR), and emissions of , CO, , HC and soot are presented to assess the quality of combustion. Engine performance analysis has been done in terms of combustion efficiency, gross work, power, torque, and integrated mean effective pressure (IMEP). The base mesh of 1.4 mm may be an appropriate choice during the injection and combustion process spanning throughout around CA from the start of injection while in the remaining simulation duration of around CA base mesh of 2 mm gives a sufficient resolution. It has been found that maximum heat release takes place in Phase-III, the mixing-controlled phase, of the combustion process. More than 98% combustion efficiency has been achieved in all the simulations. Around 99% of the total heat release and emissions production takes place within CA after top dead center (ATDC).
{"title":"In-cylinder in-depth combustion investigation for a heavy-duty diesel engine","authors":"Anam Ali, Khalid Saifullah Syed","doi":"10.1016/j.jppr.2024.09.001","DOIUrl":"10.1016/j.jppr.2024.09.001","url":null,"abstract":"<div><div>This present study is part of the design improvement process of a specified high torque low-speed engine. This work aims at carrying out an in-depth analysis of in-cylinder combustion, mesh sensitivity, and engine performance at supercharge conditions to provide a foundation for the design improvement process of the given engine. The computational fluid dynamic (CFD) simulations are carried out on a 3D sector from <span><math><mrow><mo>−</mo><mn>130</mn><mo>°</mo></mrow></math></span> to <span><math><mrow><mrow><mn>130</mn><mo>°</mo></mrow></mrow></math></span> crank angle (CA) by employing appropriate models to represent the different physical and chemical processes and using the finite volume method for solving the governing differential equations. An extensive investigation has been carried out for the choice of base mesh size and the number of local and temporal refinements to capture the phenomena happening in the combustion chamber at diverse temporal and local scales. The present results have been validated against available literature experimental and simulation results. Primary field variables and the well-known four phases of combustion have been studied for gaining in-depth insight into these phenomena. Cylinder average pressure, mean temperature, heat release rate (HRR), integrated heat release rate (IHRR), and emissions of <span><math><mrow><msub><mtext>CO</mtext><mn>2</mn></msub></mrow></math></span>, CO, <span><math><mrow><msub><mtext>NO</mtext><mi>x</mi></msub></mrow></math></span>, HC and soot are presented to assess the quality of combustion. Engine performance analysis has been done in terms of combustion efficiency, gross work, power, torque, and integrated mean effective pressure (IMEP). The base mesh of 1.4 mm may be an appropriate choice during the injection and combustion process spanning throughout around <span><math><mrow><mrow><mn>40</mn><mo>°</mo></mrow></mrow></math></span> CA from the start of injection while in the remaining simulation duration of around <span><math><mrow><mrow><mn>220</mn><mo>°</mo></mrow></mrow></math></span> CA base mesh of 2 mm gives a sufficient resolution. It has been found that maximum heat release takes place in Phase-III, the mixing-controlled phase, of the combustion process. More than 98% combustion efficiency has been achieved in all the simulations. Around 99% of the total heat release and emissions production takes place within <span><math><mrow><mrow><mn>60</mn><mo>°</mo></mrow></mrow></math></span> CA after top dead center (ATDC).</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 3","pages":"Pages 335-359"},"PeriodicalIF":5.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142356679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-01DOI: 10.1016/j.jppr.2024.08.003
Feng-Yuan Zuo , Sergio Pirozzoli
A common denominator between conical-symmetry and conical shock interaction is the spanwise pressure gradient, which perform more non-uniformity and its interaction flow is more complicated than the spanwise-homogeneous planar shock wave. Recent advances in conical-symmetry and conical shock interactions with turbulent boundary layer are reviewed in specific areas: (i) quasi-conical swept interactions due to compression ramps and sharp fins, (ii) impinging conical shock wave with interactions of plate wall, (iii) laminar double cone interactions with consideration of real-gas effects. Substantial success has been achieved in describing the phenomena of the time averaged and instantaneous flow features and the low-frequency unsteadiness, including correlations and coherent structures in the separation bubble, through complementary experimental and numerical studies of swept shock interactions. All available observations are here scrutinized to infer underlying mechanisms of interactions in conical flow, and provide theoretical foundation and hints for fluidic control techniques. Comparison with high-fidelity direct numerical simulations is used to quantified the uncertainty of RANS turbulence models in complex interactions. Regarding heat transfer, extensive studies of hypersonic flow over double cone geometries have shown that those can be predicted with reasonable accuracy, even in the presence of high-temperature effects.
{"title":"Recent progress in conical shock wave/boundary layer interaction with spanwise pressure gradient","authors":"Feng-Yuan Zuo , Sergio Pirozzoli","doi":"10.1016/j.jppr.2024.08.003","DOIUrl":"10.1016/j.jppr.2024.08.003","url":null,"abstract":"<div><div>A common denominator between conical-symmetry and conical shock interaction is the spanwise pressure gradient, which perform more non-uniformity and its interaction flow is more complicated than the spanwise-homogeneous planar shock wave. Recent advances in conical-symmetry and conical shock interactions with turbulent boundary layer are reviewed in specific areas: (i) quasi-conical swept interactions due to compression ramps and sharp fins, (ii) impinging conical shock wave with interactions of plate wall, (iii) laminar double cone interactions with consideration of real-gas effects. Substantial success has been achieved in describing the phenomena of the time averaged and instantaneous flow features and the low-frequency unsteadiness, including correlations and coherent structures in the separation bubble, through complementary experimental and numerical studies of swept shock interactions. All available observations are here scrutinized to infer underlying mechanisms of interactions in conical flow, and provide theoretical foundation and hints for fluidic control techniques. Comparison with high-fidelity direct numerical simulations is used to quantified the uncertainty of RANS turbulence models in complex interactions. Regarding heat transfer, extensive studies of hypersonic flow over double cone geometries have shown that those can be predicted with reasonable accuracy, even in the presence of high-temperature effects.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 3","pages":"Pages 295-318"},"PeriodicalIF":5.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142356776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-01DOI: 10.1016/j.jppr.2024.08.002
T. Oreyeni , M.D. Shamshuddin , A.M. Obalalu , A. Saeed , Nehad Ali Shah
Stratified thermal storage promotes energy sustainability by storing excess energy during times of low demand for later use making it possible to integrate renewable energy sources like solar and wind. This communication discusses the significance of triple stratification using the Cattaneo-Christov model in the bioconvective flow of thixotropic fluid coexisting with nanoparticles and gyrotactic microorganisms. The Cattaneo-Christov heat and mass flux is incorporated into the fluid model allowing more accurate prediction of heat and mass phenomena in the fluid system. The governing partial differential equations that describe fluid flow are parametrized to yield an ordinary differential equation system by adopting suitable transformations. The series solutions are obtained by applying the homotopy analysis method (HAM). The effects of relevant parameters on the various profiles are revealed and accurately reported. It is observed that amplified thermal stratification lowers the temperature of the fluid. Also, Brownian motion is used to illustrate the random movement of small particles suspended in liquids, and it is envisioned that the concentration distribution is significantly influenced by the Brownian motion of nanoparticles.
{"title":"Exploring the impact of stratification on the dynamics of bioconvective thixotropic fluid conveying tiny particles and Cattaneo-Christov model: Thermal storage system application","authors":"T. Oreyeni , M.D. Shamshuddin , A.M. Obalalu , A. Saeed , Nehad Ali Shah","doi":"10.1016/j.jppr.2024.08.002","DOIUrl":"10.1016/j.jppr.2024.08.002","url":null,"abstract":"<div><div>Stratified thermal storage promotes energy sustainability by storing excess energy during times of low demand for later use making it possible to integrate renewable energy sources like solar and wind. This communication discusses the significance of triple stratification using the Cattaneo-Christov model in the bioconvective flow of thixotropic fluid coexisting with nanoparticles and gyrotactic microorganisms. The Cattaneo-Christov heat and mass flux is incorporated into the fluid model allowing more accurate prediction of heat and mass phenomena in the fluid system. The governing partial differential equations that describe fluid flow are parametrized to yield an ordinary differential equation system by adopting suitable transformations. The series solutions are obtained by applying the homotopy analysis method (HAM). The effects of relevant parameters on the various profiles are revealed and accurately reported. It is observed that amplified thermal stratification lowers the temperature of the fluid. Also, Brownian motion is used to illustrate the random movement of small particles suspended in liquids, and it is envisioned that the concentration distribution is significantly influenced by the Brownian motion of nanoparticles.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 3","pages":"Pages 416-432"},"PeriodicalIF":5.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142356686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-01DOI: 10.1016/j.jppr.2023.02.008
Model-based control shows promising potential for engine performance improvement and future aero-propulsion requirements. In this paper, an auto-updating thrust variation mitigation (AuTVM) control approach using on-board model strategies is proposed for gas turbine aero-engines under in-service degradation effects, which aims at active thrust regulation and acceleration protection in a simultaneous way. The AuTVM control is integrated with an on-line block, based on a reliable on-board engine model, and an off-line part for the periodical update of control parameters via post-flight engine monitoring data. The core feature of the AuTVM control is a set of auto-updating loops within the on-line part, including thrust regulation loop, surge margin loop, turbine entry temperature loop, and the steady loop, whose control parameters are periodically adjusted with increasing flight cycles. Meanwhile, an industrial sensor-based baseline controller and two tailored model-based controllers, i.e., a thrust variation mitigation (TVM) controller with fixed gains and a self-enhancing active transient protection (SeATP) controller with pro-active transient protection and passive thrust control, are also developed as comparison bases. Numerical simulations for idle to full-power acceleration tests are carried on a validated aero-thermal turbofan engine model using publicly available degradation data. Simulation results demonstrate that both new engines and severely degraded engines regulated by the AuTVM controller show significant thrust response enhancement, compared to the baseline controller. Moreover, thrust variation at the maximum steady state of degraded engines, which exists within the SeATP controller and the baseline controller, is suppressed by the proposed AuTVM controller. Robustness analysis against degradation uncertainties and sensor accuracy confirms that the AuTVM controller owns a closer maximum steady-state thrust distribution to the desired value than those of the SeATP and the baseline controller while utilizing transient margins of controlled engines more effectively. Hence, the control performance of the AuTVM controller for in-service engines is guaranteed.
{"title":"Auto-updating model-based control for thrust variation mitigation and acceleration performance enhancement of gas turbine aero-engines","authors":"","doi":"10.1016/j.jppr.2023.02.008","DOIUrl":"10.1016/j.jppr.2023.02.008","url":null,"abstract":"<div><div>Model-based control shows promising potential for engine performance improvement and future aero-propulsion requirements. In this paper, an auto-updating thrust variation mitigation (AuTVM) control approach using on-board model strategies is proposed for gas turbine aero-engines under in-service degradation effects, which aims at active thrust regulation and acceleration protection in a simultaneous way. The AuTVM control is integrated with an on-line block, based on a reliable on-board engine model, and an off-line part for the periodical update of control parameters via post-flight engine monitoring data. The core feature of the AuTVM control is a set of auto-updating loops within the on-line part, including thrust regulation loop, surge margin loop, turbine entry temperature loop, and the steady loop, whose control parameters are periodically adjusted with increasing flight cycles. Meanwhile, an industrial sensor-based baseline controller and two tailored model-based controllers, i.e., a thrust variation mitigation (TVM) controller with fixed gains and a self-enhancing active transient protection (SeATP) controller with pro-active transient protection and passive thrust control, are also developed as comparison bases. Numerical simulations for idle to full-power acceleration tests are carried on a validated aero-thermal turbofan engine model using publicly available degradation data. Simulation results demonstrate that both new engines and severely degraded engines regulated by the AuTVM controller show significant thrust response enhancement, compared to the baseline controller. Moreover, thrust variation at the maximum steady state of degraded engines, which exists within the SeATP controller and the baseline controller, is suppressed by the proposed AuTVM controller. Robustness analysis against degradation uncertainties and sensor accuracy confirms that the AuTVM controller owns a closer maximum steady-state thrust distribution to the desired value than those of the SeATP and the baseline controller while utilizing transient margins of controlled engines more effectively. Hence, the control performance of the AuTVM controller for in-service engines is guaranteed.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 3","pages":"Pages 394-415"},"PeriodicalIF":5.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138519261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01DOI: 10.1016/j.jppr.2024.04.001
Yu Zhou , Yue Song , Shuai Zhao , Xueyu Li , Longtao Shao , Huansong Yan , Zheng Xu , Shuiting Ding
Limited by the poor transient response performance of turbochargers, the dynamic performance of aviation piston engines tends to deteriorate. In a bid to enhance the turbocharger's acceleration capabilities, this study scrutinizes various factors impacting its performance. Based on the operational principles and transient response process of the turbocharger, three types of inertia—namely, aerodynamic inertia (ADI), thermal inertia (TI), and mechanical inertia (MI) — are identified and addressed for design. To begin, this paper pioneers the innovative definition of a method for evaluating the transient response performance of the turbocharger. This method incorporates the introduction of an ADI parameter, inspired by the definition of MI. Subsequently, a thin-walled volute design with a low Biot number and a lightweight turbine impeller is introduced to reduce the turbocharger's TI and MI. The simulation results of the flow field distribution within the volute and diffuser demonstrate the comprehensive design method's effectiveness in improving gas pressure and temperature distributions in these components. Notably, the pressure distribution fluctuation in the constant moment-of-momentum volute (CMV) is 62.8% lower than that in the constant velocity moment volute (CVMV). The low-TI thin-walled volute not only enhances the turbocharger's response speed but also reduces its weight by approximately 40%. The impact of three types of inertia on the engine's response speed is quantified as follows: ADI (94%) > MI (5%) > TI (1%). This conclusion has been verified through test results of both the turbocharger and the engine. This design method not only significantly improves the turbocharger's response performance but also offers valuable insights for the optimal design of other blade mechanical systems.
受限于涡轮增压器较差的瞬态响应性能，航空活塞发动机的动态性能趋于恶化。为了提高涡轮增压器的加速能力，本研究仔细研究了影响其性能的各种因素。根据涡轮增压器的工作原理和瞬态响应过程，确定了三种惯性，即空气动力惯性（ADI）、热惯性（TI）和机械惯性（MI），并针对这三种惯性进行了设计。首先，本文开创性地定义了评估涡轮增压器瞬态响应性能的方法。受 MI 定义的启发，该方法引入了 ADI 参数。随后，引入了具有低 Biot 数的薄壁涡流设计和轻质涡轮叶轮，以降低涡轮增压器的 TI 和 MI。涡道和扩散器内流场分布的模拟结果表明，综合设计方法能有效改善这些部件内的气体压力和温度分布。值得注意的是，恒定力矩涡道（CMV）的压力分布波动比恒定速度力矩涡道（CVMV）低 62.8%。低 TI 薄壁涡道不仅提高了涡轮增压器的响应速度，还将其重量减轻了约 40%。三种惯性对发动机响应速度的影响量化如下：ADI（94%）；MI（5%）；TI（1%）。涡轮增压器和发动机的测试结果验证了这一结论。这种设计方法不仅大大提高了涡轮增压器的响应性能，还为其他叶片机械系统的优化设计提供了宝贵的启示。
{"title":"A comprehensive aerodynamic-thermal-mechanical design method for fast response turbocharger applied in aviation piston engines","authors":"Yu Zhou , Yue Song , Shuai Zhao , Xueyu Li , Longtao Shao , Huansong Yan , Zheng Xu , Shuiting Ding","doi":"10.1016/j.jppr.2024.04.001","DOIUrl":"10.1016/j.jppr.2024.04.001","url":null,"abstract":"<div><p>Limited by the poor transient response performance of turbochargers, the dynamic performance of aviation piston engines tends to deteriorate. In a bid to enhance the turbocharger's acceleration capabilities, this study scrutinizes various factors impacting its performance. Based on the operational principles and transient response process of the turbocharger, three types of inertia—namely, aerodynamic inertia (ADI), thermal inertia (TI), and mechanical inertia (MI) — are identified and addressed for design. To begin, this paper pioneers the innovative definition of a method for evaluating the transient response performance of the turbocharger. This method incorporates the introduction of an ADI parameter, inspired by the definition of MI. Subsequently, a thin-walled volute design with a low Biot number and a lightweight turbine impeller is introduced to reduce the turbocharger's TI and MI. The simulation results of the flow field distribution within the volute and diffuser demonstrate the comprehensive design method's effectiveness in improving gas pressure and temperature distributions in these components. Notably, the pressure distribution fluctuation in the constant moment-of-momentum volute (CMV) is 62.8% lower than that in the constant velocity moment volute (CVMV). The low-TI thin-walled volute not only enhances the turbocharger's response speed but also reduces its weight by approximately 40%. The impact of three types of inertia on the engine's response speed is quantified as follows: ADI (94%) > MI (5%) > TI (1%). This conclusion has been verified through test results of both the turbocharger and the engine. This design method not only significantly improves the turbocharger's response performance but also offers valuable insights for the optimal design of other blade mechanical systems.</p></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 2","pages":"Pages 145-165"},"PeriodicalIF":5.3,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2212540X24000221/pdfft?md5=dca90ce10bca21e87aa3117101f22f3f&pid=1-s2.0-S2212540X24000221-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141040950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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