Pub Date : 2024-12-01DOI: 10.1016/j.jppr.2024.11.005
Ahmed M. Daabo , Ali Basem , Raqeeb H. Rajab , Shahad S. Ibrahim , Qusay R. Al-Amir , Hudhaifa Hamzah , Haider K. Easa
In recent years, research on enhancing the efficiency of clean and renewable energy systems has increased. This study examines how a micro-scale solar Brayton cycle application performs about the conical cavity thermal receiver shape. Additionally, it establishes the ideal receiver configuration under consideration. The new work explicitly addresses the optimization of a microscale conical model, building on earlier studies by the research team that stressed the significance of reducing total heat losses. The receiver model was created using Design Modeler and treated using CFD analysis in ANSYS 2021R2 Workbench software to limit the convective mode of heat loss. Surface optimization techniques were then used, and the results were examined. To confirm the achieved results, the direct optimization method was also utilized, and it gave the same results. The internal height and the two edges on the bottom width of the receiver were found to have the greatest influence on the value of the heat transfer coefficient. Thermally, the dimensions of the optimized conical shape were found to be 384, 198, 114, 48 and 57 mm for the internal height, total width, top width, left edge and right edge respectively. The results of this investigation showed that by reducing the heat transfer coefficient by up to 90%, the tested shape's thermal performance was significantly improved. It consequently led to an increase in overall system efficiency of around 1.3%–1.95%.
{"title":"Optimization of a micro-scale conical cavity receiver: A state-of-the-art approach","authors":"Ahmed M. Daabo , Ali Basem , Raqeeb H. Rajab , Shahad S. Ibrahim , Qusay R. Al-Amir , Hudhaifa Hamzah , Haider K. Easa","doi":"10.1016/j.jppr.2024.11.005","DOIUrl":"10.1016/j.jppr.2024.11.005","url":null,"abstract":"<div><div>In recent years, research on enhancing the efficiency of clean and renewable energy systems has increased. This study examines how a micro-scale solar Brayton cycle application performs about the conical cavity thermal receiver shape. Additionally, it establishes the ideal receiver configuration under consideration. The new work explicitly addresses the optimization of a microscale conical model, building on earlier studies by the research team that stressed the significance of reducing total heat losses. The receiver model was created using Design Modeler and treated using CFD analysis in ANSYS 2021R2 Workbench software to limit the convective mode of heat loss. Surface optimization techniques were then used, and the results were examined. To confirm the achieved results, the direct optimization method was also utilized, and it gave the same results. The internal height and the two edges on the bottom width of the receiver were found to have the greatest influence on the value of the heat transfer coefficient. Thermally, the dimensions of the optimized conical shape were found to be 384, 198, 114, 48 and 57 mm for the internal height, total width, top width, left edge and right edge respectively. The results of this investigation showed that by reducing the heat transfer coefficient by up to 90%, the tested shape's thermal performance was significantly improved. It consequently led to an increase in overall system efficiency of around 1.3%–1.95%.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 4","pages":"Pages 487-502"},"PeriodicalIF":5.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101206","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 : 2024-12-01DOI: 10.1016/j.jppr.2024.11.004
M. Johari , H.A. Hoshyar , D.D. Ganji
Heat pipes are crucial in a wide range of applications, ranging from space satellites and industrial systems to electronic cooling and X-ray tube thermal management. This study introduces a method investigation into vapor flows within a flat plate heat pipe, utilizing the collocation method (CM) and the fourth-order Runge-Kutta-Fehlberg (RKF45) method. Building on previous efforts, this work explores the effects of the evaporator-to-condenser length ratio and Reynolds number on velocity and pressure distributions along the entire heat pipe. The significance of this research lies in its ability to elucidate critical parameters that directly influence heat pipe performance, offering deeper insights that are vital for optimizing design and efficiency. The primary motivation of this study is to fill existing gaps in the literature by developing a comprehensive analytical model that accurately characterizes vapor and liquid flow in asymmetrical flat plate heat pipes. The model's validity is confirmed through a satisfactory agreement with numerical results, underscoring the reliability of the methods used. Notably, the findings reveal that higher Reynolds numbers reduce pressure drop and shift the maximum velocity toward the bottom wick in the evaporation section, providing valuable guidance for future design improvements. Additionally, this research presents a powerful method for solving non-linear ordinary differential equations, offering significant time savings and enabling predictive functions. These contributions are poised to enhance the performance of thermal management systems across various engineering disciplines.
{"title":"Numerical and analytical investigation of vapor flows in a flat plate heat pipe: Effects of length ratio and Reynolds number","authors":"M. Johari , H.A. Hoshyar , D.D. Ganji","doi":"10.1016/j.jppr.2024.11.004","DOIUrl":"10.1016/j.jppr.2024.11.004","url":null,"abstract":"<div><div>Heat pipes are crucial in a wide range of applications, ranging from space satellites and industrial systems to electronic cooling and X-ray tube thermal management. This study introduces a method investigation into vapor flows within a flat plate heat pipe, utilizing the collocation method (CM) and the fourth-order Runge-Kutta-Fehlberg (RKF45) method. Building on previous efforts, this work explores the effects of the evaporator-to-condenser length ratio and Reynolds number on velocity and pressure distributions along the entire heat pipe. The significance of this research lies in its ability to elucidate critical parameters that directly influence heat pipe performance, offering deeper insights that are vital for optimizing design and efficiency. The primary motivation of this study is to fill existing gaps in the literature by developing a comprehensive analytical model that accurately characterizes vapor and liquid flow in asymmetrical flat plate heat pipes. The model's validity is confirmed through a satisfactory agreement with numerical results, underscoring the reliability of the methods used. Notably, the findings reveal that higher Reynolds numbers reduce pressure drop and shift the maximum velocity toward the bottom wick in the evaporation section, providing valuable guidance for future design improvements. Additionally, this research presents a powerful method for solving non-linear ordinary differential equations, offering significant time savings and enabling predictive functions. These contributions are poised to enhance the performance of thermal management systems across various engineering disciplines.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 4","pages":"Pages 523-533"},"PeriodicalIF":5.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101207","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 : 2024-12-01DOI: 10.1016/j.jppr.2024.04.003
Ping Huang , Xueqin Bu , Guiping Lin , Quanyong Xu , Chunhua Xiao
This paper investigates the coupling characteristics of motion and heat transfer between airflow and ice crystals in a single-stage compressor. The motion and phase transition process of ice crystal particles were modeled using the Eulerian trajectory method and validated. The heat and mass transfer processes between airflows in compressor and ice crystals were simulated and analyzed. The melting ratio, catching efficiency, and sticking efficiency of ice crystals were obtained, as well as variations in temperature and humidity ratio in the airflow due to ice crystal phase change. The results show that the ice crystals sticking to blades in the single-stage compressor account for 10.35% of the impact mass flow rate. Additionally, the presence of ice crystals causes a 0.466 K decrease in the airflow temperature and a 0.114 g/kg(a) increase in the humidity ratio. The theoretical model and calculation method provide strong support for future ice crystal icing simulations and engine operation research.
{"title":"Simulation of coupling characteristics of motion and heat transfer between airflow and ice crystals in a single-stage compressor","authors":"Ping Huang , Xueqin Bu , Guiping Lin , Quanyong Xu , Chunhua Xiao","doi":"10.1016/j.jppr.2024.04.003","DOIUrl":"10.1016/j.jppr.2024.04.003","url":null,"abstract":"<div><div>This paper investigates the coupling characteristics of motion and heat transfer between airflow and ice crystals in a single-stage compressor. The motion and phase transition process of ice crystal particles were modeled using the Eulerian trajectory method and validated. The heat and mass transfer processes between airflows in compressor and ice crystals were simulated and analyzed. The melting ratio, catching efficiency, and sticking efficiency of ice crystals were obtained, as well as variations in temperature and humidity ratio in the airflow due to ice crystal phase change. The results show that the ice crystals sticking to blades in the single-stage compressor account for 10.35% of the impact mass flow rate. Additionally, the presence of ice crystals causes a 0.466 K decrease in the airflow temperature and a 0.114 g/kg(a) increase in the humidity ratio. The theoretical model and calculation method provide strong support for future ice crystal icing simulations and engine operation research.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 4","pages":"Pages 570-585"},"PeriodicalIF":5.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141032462","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 : 2024-12-01DOI: 10.1016/j.jppr.2024.02.007
Jian Zhang , Min Zhang , Juan Du , Kai Yue , Xinyi Wang , Chen Yang , Hongwu Zhang
Gas turbine is a promising device for power generation and propulsion either using traditional or renewable energy fuels. One of its key problems is the flow instability of compressors especially with the increase in blade load and changeable working environment. To intelligently and efficiently inhibit flow separation and enhance the pressure rise ability of highly loaded compressors under variable operating conditions, a novel flow control technique termed as adaptive Coanda jet control (ACJC) is proposed in this paper for a compressor stator cascade with a high diffusion factor of 0.66. To realize the ACJC strategy, an incidence angle (IA) prediction model and an optimal injection mass flow rate (OIMFR) prediction model are established by adopting single factor analysis of variance, principal component analysis and Back Propagation Neural Network (BPNN) methods. Two inlet Mach numbers including 0.1 and 0.4 are considered to represent incompressible and compressible flow conditions, and different inlet incidence angles are involved to model various off-design working situations of the real compressor. Effectiveness of the ACJC system is evaluated using numerical simulations are performed to understand the effects of the injection mass flow ratio on the flow field and aerodynamic performance of the blade cascade. Results indicate that the ACJC system can accurately predict the optimal injection mass flow ratio that can achieve the minimum flow loss at each incidence angle. Compared to the cascade without ACJC under the incidence angel of 5°, the optimal injection mass flow ratio being 1.27% and 1.20% can reduce the total pressure loss coefficient by 18.88% and 21.56% for incoming Mach number being 0.1 and 0.4, respectively.
{"title":"Adaptive Coanda jet control for performance improvement of a highly loaded compressor cascade","authors":"Jian Zhang , Min Zhang , Juan Du , Kai Yue , Xinyi Wang , Chen Yang , Hongwu Zhang","doi":"10.1016/j.jppr.2024.02.007","DOIUrl":"10.1016/j.jppr.2024.02.007","url":null,"abstract":"<div><div>Gas turbine is a promising device for power generation and propulsion either using traditional or renewable energy fuels. One of its key problems is the flow instability of compressors especially with the increase in blade load and changeable working environment. To intelligently and efficiently inhibit flow separation and enhance the pressure rise ability of highly loaded compressors under variable operating conditions, a novel flow control technique termed as adaptive Coanda jet control (ACJC) is proposed in this paper for a compressor stator cascade with a high diffusion factor of 0.66. To realize the ACJC strategy, an incidence angle (IA) prediction model and an optimal injection mass flow rate (OIMFR) prediction model are established by adopting single factor analysis of variance, principal component analysis and Back Propagation Neural Network (BPNN) methods. Two inlet Mach numbers including 0.1 and 0.4 are considered to represent incompressible and compressible flow conditions, and different inlet incidence angles are involved to model various off-design working situations of the real compressor. Effectiveness of the ACJC system is evaluated using numerical simulations are performed to understand the effects of the injection mass flow ratio on the flow field and aerodynamic performance of the blade cascade. Results indicate that the ACJC system can accurately predict the optimal injection mass flow ratio that can achieve the minimum flow loss at each incidence angle. Compared to the cascade without ACJC under the incidence angel of 5°, the optimal injection mass flow ratio being 1.27% and 1.20% can reduce the total pressure loss coefficient by 18.88% and 21.56% for incoming Mach number being 0.1 and 0.4, respectively.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 4","pages":"Pages 534-552"},"PeriodicalIF":5.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141048446","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 : 2024-12-01DOI: 10.1016/j.jppr.2024.11.002
Ahmed Zeeshan , Muhammad Imran Khan , Aaqib Majeed , Mohammed Sh. Alhodaly
The authors use a temporal stability analysis to examine the hydrodynamics performance of flow response quantities to investigate the impacts of pertained parameters on Casson nanofluid over a porous shrinking wedge. Thermal analysis is performed in the current flow with thermal radiation and the viscous dissipation effect. Boungiorno's model is used to develop flow equations for Casson nanofluid over a shrinking wedge. An efficient similarity variable is used to change flow equations (PDEs) into dimensionless ordinary differential equations (ODEs) and numerical results are evaluated using MATLAB built-in routine bvp4c. The consequence of this analysis reveals that the impact of active parameters on momentum, thermal and concentration boundary layer distributions are calculated. The dual nature of flow response output i.e. is computed for various values of , and the critical value is found to be , , and . It is perceived that the first (upper branch) solution rises for the temperature profile when the value of thermal radiation is increased and it has the opposite impact on the concentration profile. Thermal radiation has the same critical value for and . The perturbation scheme is applied to the boundary layer problem to obtain the eigenvalues problem. The unsteady solution converges to steady solution for when . However, an unsteady solution diverges to a steady solution for when . It is found that the boundary layer thickness for the second (lower branch) solution is higher than the first (upper branch) solution. This investigation is the evidence that the first (upper branch) solution is
{"title":"Temporal stability analysis and thermal performance of non-Newtonian nanofluid over a shrinking wedge","authors":"Ahmed Zeeshan , Muhammad Imran Khan , Aaqib Majeed , Mohammed Sh. Alhodaly","doi":"10.1016/j.jppr.2024.11.002","DOIUrl":"10.1016/j.jppr.2024.11.002","url":null,"abstract":"<div><div>The authors use a temporal stability analysis to examine the hydrodynamics performance of flow response quantities to investigate the impacts of pertained parameters on Casson nanofluid over a porous shrinking wedge. Thermal analysis is performed in the current flow with thermal radiation and the viscous dissipation effect. Boungiorno's model is used to develop flow equations for Casson nanofluid over a shrinking wedge. An efficient similarity variable is used to change flow equations (PDEs) into dimensionless ordinary differential equations (ODEs) and numerical results are evaluated using MATLAB built-in routine bvp4c. The consequence of this analysis reveals that the impact of active parameters on momentum, thermal and concentration boundary layer distributions are calculated. The dual nature of flow response output i.e. <span><math><mrow><mi>C</mi><msub><mi>f</mi><mi>x</mi></msub></mrow></math></span> is computed for various values of <span><math><mrow><msub><mi>β</mi><mi>T</mi></msub><mo>=</mo><mn>2.5</mn><mo>,</mo><mn>3.5</mn><mo>,</mo><mn>4.5</mn></mrow></math></span>, and the critical value is found to be <span><math><mrow><mo>−</mo><mn>1.544996</mn></mrow></math></span>, <span><math><mrow><mo>−</mo><mn>1.591</mn></mrow></math></span>, and <span><math><mrow><mo>−</mo><mn>1.66396</mn></mrow></math></span>. It is perceived that the first (upper branch) solution rises for the temperature profile when the value of thermal radiation is increased and it has the opposite impact on the concentration profile. Thermal radiation has the same critical value for <span><math><mrow><msub><mrow><mi>N</mi><mi>u</mi></mrow><mi>x</mi></msub></mrow></math></span> and <span><math><mrow><msub><mrow><mi>S</mi><mi>h</mi></mrow><mi>x</mi></msub></mrow></math></span>. The perturbation scheme is applied to the boundary layer problem to obtain the eigenvalues problem. The unsteady solution <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mrow><mi>η</mi><mo>,</mo><mi>τ</mi></mrow><mo>)</mo></mrow></mrow></math></span> converges to steady solution <span><math><mrow><msub><mi>f</mi><mi>o</mi></msub><mrow><mo>(</mo><mi>η</mi><mo>)</mo></mrow></mrow></math></span> for <span><math><mrow><mi>τ</mi><mo>→</mo><mi>∞</mi></mrow></math></span> when <span><math><mrow><mi>γ</mi><mo>≥</mo><mn>0</mn></mrow></math></span>. However, an unsteady solution <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mrow><mi>η</mi><mo>,</mo><mi>τ</mi></mrow><mo>)</mo></mrow></mrow></math></span> diverges to a steady solution <span><math><mrow><msub><mi>f</mi><mi>o</mi></msub><mrow><mo>(</mo><mi>η</mi><mo>)</mo></mrow></mrow></math></span> for <span><math><mrow><mi>τ</mi><mo>→</mo><mi>∞</mi></mrow></math></span> when <span><math><mrow><mi>γ</mi><mo><</mo><mn>0</mn></mrow></math></span>. It is found that the boundary layer thickness for the second (lower branch) solution is higher than the first (upper branch) solution. This investigation is the evidence that the first (upper branch) solution is ","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 4","pages":"Pages 586-596"},"PeriodicalIF":5.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101182","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 : 2024-12-01DOI: 10.1016/j.jppr.2024.11.001
Hatem Kayed , Mostafa M. Abdel Aziz , M.S. Gad
The inherent drawbacks of biodiesel, particularly its poor performance in cold climates, necessitate the use of nano-additives to improve its cold flow properties such as the cloud point (CP), pour point (PP), and cold filter plugging point (CFPP). In this study, transesterification was employed to produce methyl esters from waste cooking oil, corn oil, and jatropha oil. These biodiesels were blended with diesel fuel at a 20% biodiesel and 80% diesel volume ratio and enriched with nano-Al2O3 at concentrations of 25, 50, and 100 mg/L. The aim of this study is to evaluate the impact of nano-Al2O3 on engine combustion, performance, exergy, and emissions of diesel engines using different biodiesel feedstocks. The addition of nano-Al2O3 to methyl ester mixtures (JB20A100, CB20A100, and WB20A100) resulted in enhancements in thermal efficiency by 8%, 11%, and 13%, respectively. CO emissions were reduced by 12%, 17%, and 22% for jatropha, corn, and waste cooking oil blends, respectively, with 100 ppm alumina. This reduction in CO emissions can be linked to the enhanced oxidation process facilitated by the high surface area of the nanoparticles, which act as catalysts, promoting more complete combustion. Similarly, UHC emissions decreased by 14%, 18%, and 23%, and smoke concentrations were significantly reduced by 14%, 17%, and 24% across the biodiesel blends. However, the introduction of alumina led to the rise in NOx emissions by 9%, 15%, and 19% for JB20A100, CB20A100, and WB20A100, respectively. The study also revealed increases in cylinder pressure by 2%, 4%, and 8%, and maximum heat release rates by 3%, 6%, and 10% for JB20, CB20, and WB20, respectively, upon the incorporation of 100 ppm Al2O3. Exergetic efficiencies improved by 6%, 17%, and 23% for JB20A100, CB20A100, and WB20A100, respectively, and the sustainability index showed enhancements of 2%, 4%, and 7%. Among the tested blends, WB20 with 100 ppm of nano-Al2O3 demonstrated the most promising results, significantly improving engine exergy, combustion, and performance while mitigating emissions to acceptable levels. This study underscores the potential of nano-additives to advance the sustainability and efficiency of diesel engine operations, particularly in cold climate.
{"title":"Enriching various biodiesel feedstocks with Al2O3 nanoparticles in diesel engines: Performance, emissions, and exergy analysis","authors":"Hatem Kayed , Mostafa M. Abdel Aziz , M.S. Gad","doi":"10.1016/j.jppr.2024.11.001","DOIUrl":"10.1016/j.jppr.2024.11.001","url":null,"abstract":"<div><div>The inherent drawbacks of biodiesel, particularly its poor performance in cold climates, necessitate the use of nano-additives to improve its cold flow properties such as the cloud point (CP), pour point (PP), and cold filter plugging point (CFPP). In this study, transesterification was employed to produce methyl esters from waste cooking oil, corn oil, and jatropha oil. These biodiesels were blended with diesel fuel at a 20% biodiesel and 80% diesel volume ratio and enriched with nano-Al<sub>2</sub>O<sub>3</sub> at concentrations of 25, 50, and 100 mg/L. The aim of this study is to evaluate the impact of nano-Al<sub>2</sub>O<sub>3</sub> on engine combustion, performance, exergy, and emissions of diesel engines using different biodiesel feedstocks. The addition of nano-Al<sub>2</sub>O<sub>3</sub> to methyl ester mixtures (JB20A100, CB20A100, and WB20A100) resulted in enhancements in thermal efficiency by 8%, 11%, and 13%, respectively. CO emissions were reduced by 12%, 17%, and 22% for jatropha, corn, and waste cooking oil blends, respectively, with 100 ppm alumina. This reduction in CO emissions can be linked to the enhanced oxidation process facilitated by the high surface area of the nanoparticles, which act as catalysts, promoting more complete combustion. Similarly, UHC emissions decreased by 14%, 18%, and 23%, and smoke concentrations were significantly reduced by 14%, 17%, and 24% across the biodiesel blends. However, the introduction of alumina led to the rise in NO<sub>x</sub> emissions by 9%, 15%, and 19% for JB20A100, CB20A100, and WB20A100, respectively. The study also revealed increases in cylinder pressure by 2%, 4%, and 8%, and maximum heat release rates by 3%, 6%, and 10% for JB20, CB20, and WB20, respectively, upon the incorporation of 100 ppm Al<sub>2</sub>O<sub>3</sub>. Exergetic efficiencies improved by 6%, 17%, and 23% for JB20A100, CB20A100, and WB20A100, respectively, and the sustainability index showed enhancements of 2%, 4%, and 7%. Among the tested blends, WB20 with 100 ppm of nano-Al<sub>2</sub>O<sub>3</sub> demonstrated the most promising results, significantly improving engine exergy, combustion, and performance while mitigating emissions to acceptable levels. This study underscores the potential of nano-additives to advance the sustainability and efficiency of diesel engine operations, particularly in cold climate.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 4","pages":"Pages 553-569"},"PeriodicalIF":5.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101208","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 : 2024-12-01DOI: 10.1016/j.jppr.2024.10.001
J. Zhou , F. Taccogna , P. Fajardo , E. Ahedo
Plasma chemistry of main Earth atmospheric components in VLEOs is implemented in a hybrid 2D axisymmetric simulation code to assess the air-breathing concept in an electrodeless plasma thruster. Relevant electron-heavy species collisions for diatomic molecules, and atom associative wall recombination into molecules are included. Simulations are run by injecting 1 mg/s of Xe, N2 and O independently for powers between 10 and 3000 W. The performances and trends of plasma response for N2 and O are similar to Xe but displaced to higher powers. Since they have lighter elementary masses, a higher plasma density is generated and more electrons need to be heated. At optimum power, the thrust efficiency for N2 and O surpasses that of Xe, which is caused by the excess of neutral re-ionization and the associated inelastic and wall losses. Additional simulations are run injecting 50/50 of N2/O to study the thruster operation for propellant mixtures, and the performances are found to be linear combinations of those of each propellant in the absence of collisions between heavy species. Injection of O2 is also studied for the impact of the possible associative recombination of O at the intake walls, and the performances are found similar to those of O due to the strong molecular dissociation inside the thruster.
{"title":"A study of an air-breathing electrodeless plasma thruster discharge","authors":"J. Zhou , F. Taccogna , P. Fajardo , E. Ahedo","doi":"10.1016/j.jppr.2024.10.001","DOIUrl":"10.1016/j.jppr.2024.10.001","url":null,"abstract":"<div><div>Plasma chemistry of main Earth atmospheric components in VLEOs is implemented in a hybrid 2D axisymmetric simulation code to assess the air-breathing concept in an electrodeless plasma thruster. Relevant electron-heavy species collisions for diatomic molecules, and atom associative wall recombination into molecules are included. Simulations are run by injecting 1 mg/s of Xe, N<sub>2</sub> and O independently for powers between 10 and 3000 W. The performances and trends of plasma response for N<sub>2</sub> and O are similar to Xe but displaced to higher powers. Since they have lighter elementary masses, a higher plasma density is generated and more electrons need to be heated. At optimum power, the thrust efficiency for N<sub>2</sub> and O surpasses that of Xe, which is caused by the excess of neutral re-ionization and the associated inelastic and wall losses. Additional simulations are run injecting 50/50 of N<sub>2</sub>/O to study the thruster operation for propellant mixtures, and the performances are found to be linear combinations of those of each propellant in the absence of collisions between heavy species. Injection of O<sub>2</sub> is also studied for the impact of the possible associative recombination of O at the intake walls, and the performances are found similar to those of O due to the strong molecular dissociation inside the thruster.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 4","pages":"Pages 459-474"},"PeriodicalIF":5.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101205","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 : 2024-12-01DOI: 10.1016/j.jppr.2024.11.003
Mohammed Echarif Aguida, Yanbo Che, Jianxiong Yang
This comprehensive study delves into the current state and future prospects of Electrical Power Systems (EPSs) in More Electric Aircraft (MEA). The paper begins by examining the limitations of traditional aircraft systems, such as hydraulic and pneumatic systems, and explores the technological shift towards advanced electrical systems in MEA. Key innovations, including High-Voltage distribution networks, Variable Speed Constant Frequency (VSCF) systems, and Wide Bandgap (WBG) semiconductors, highlighted for their role in enhancing efficiency, reliability, and overall system performance. The study further analyzes the integration of hybrid-electric propulsion and its implications for both military and commercial aircraft, focusing on environmental benefits and operational cost savings. The development and challenges of Power Electronics Converters (PECs), batteries, and the Ram Air Turbine (RAT) systems discussed, emphasizing the need for continued research to achieve widespread adoption in civil aviation. In exploring future trends, the paper considers the potential of fuel cell technologies, advanced energy storage systems, and the evolution of Power Electronics (PEs). The importance of academia-industry collaboration underscored, with examples provided to illustrate how such partnerships can accelerate the development of advanced electrical power systems for sustainable aviation. The conclusion highlights the ongoing advancements and challenges in realizing the MEA concept, pointing to a more efficient, environmentally friendly, and sustainable future for the aviation industry.
{"title":"Technological advancements and future prospects of electrical power systems for sustainable more electric aircraft","authors":"Mohammed Echarif Aguida, Yanbo Che, Jianxiong Yang","doi":"10.1016/j.jppr.2024.11.003","DOIUrl":"10.1016/j.jppr.2024.11.003","url":null,"abstract":"<div><div>This comprehensive study delves into the current state and future prospects of Electrical Power Systems (EPSs) in More Electric Aircraft (MEA). The paper begins by examining the limitations of traditional aircraft systems, such as hydraulic and pneumatic systems, and explores the technological shift towards advanced electrical systems in MEA. Key innovations, including High-Voltage distribution networks, Variable Speed Constant Frequency (VSCF) systems, and Wide Bandgap (WBG) semiconductors, highlighted for their role in enhancing efficiency, reliability, and overall system performance. The study further analyzes the integration of hybrid-electric propulsion and its implications for both military and commercial aircraft, focusing on environmental benefits and operational cost savings. The development and challenges of Power Electronics Converters (PECs), batteries, and the Ram Air Turbine (RAT) systems discussed, emphasizing the need for continued research to achieve widespread adoption in civil aviation. In exploring future trends, the paper considers the potential of fuel cell technologies, advanced energy storage systems, and the evolution of Power Electronics (PEs). The importance of academia-industry collaboration underscored, with examples provided to illustrate how such partnerships can accelerate the development of advanced electrical power systems for sustainable aviation. The conclusion highlights the ongoing advancements and challenges in realizing the MEA concept, pointing to a more efficient, environmentally friendly, and sustainable future for the aviation industry.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 4","pages":"Pages 475-486"},"PeriodicalIF":5.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101251","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 : 2024-12-01DOI: 10.1016/j.jppr.2023.07.003
Guo Li , Huimin Zhou , Junbo Liu , Shuyang Xia , Shuiting Ding
Anomaly distribution is an essential input for the probabilistic damage tolerance assessment, which is required by the airworthiness certification criteria Federal Aviation Regulation (FAR) 33.70. The default anomaly distribution of hole features has been established and published in airworthiness advisory circular 33.70-2 based on historical anomaly data collected from cracked or ruptured parts recorded in laboratory analysis reports of the special industries before 2005. However, for other industries, this default anomaly distribution fails to reflect the machining level of these industries. Besides, insufficient historical maintenance anomaly data makes the mathematical model of the default distribution inapplicable, and few models can deal with the production data. Therefore, this paper proposes a model for achieving the anomaly distribution of hole features induced by machine or maintenance process, including collecting anomaly data, deriving the exceedance number by the probability of detection (POD), conducting the curve fitting process, and calibrating and modifying the anomaly distribution. The anomaly distribution and the probability of failure (POF) are dependent on defect numbers as well as confidence levels. To recommend the number of collected data and the correction factor for the POFs with different sample numbers and confidence levels, the sensitivity analysis is conducted by quantifying the influence of the anomaly distributions of different anomaly numbers on the POFs. Results show that when the anomaly number is 25, the differences between the POFs are less than 32.9%, and a 1.329 correction factor is supposed to modify the POF. When the anomaly number is larger than 50, a 1.2 correction factor is supposed to obtain the most conservative risk value with a 95% confidence level.
{"title":"Anomaly distribution acquisition method for probabilistic damage tolerance assessment of hole features","authors":"Guo Li , Huimin Zhou , Junbo Liu , Shuyang Xia , Shuiting Ding","doi":"10.1016/j.jppr.2023.07.003","DOIUrl":"10.1016/j.jppr.2023.07.003","url":null,"abstract":"<div><div>Anomaly distribution is an essential input for the probabilistic damage tolerance assessment, which is required by the airworthiness certification criteria Federal Aviation Regulation (FAR) 33.70. The default anomaly distribution of hole features has been established and published in airworthiness advisory circular 33.70-2 based on historical anomaly data collected from cracked or ruptured parts recorded in laboratory analysis reports of the special industries before 2005. However, for other industries, this default anomaly distribution fails to reflect the machining level of these industries. Besides, insufficient historical maintenance anomaly data makes the mathematical model of the default distribution inapplicable, and few models can deal with the production data. Therefore, this paper proposes a model for achieving the anomaly distribution of hole features induced by machine or maintenance process, including collecting anomaly data, deriving the exceedance number by the probability of detection (POD), conducting the curve fitting process, and calibrating and modifying the anomaly distribution. The anomaly distribution and the probability of failure (POF) are dependent on defect numbers as well as confidence levels. To recommend the number of collected data and the correction factor for the POFs with different sample numbers and confidence levels, the sensitivity analysis is conducted by quantifying the influence of the anomaly distributions of different anomaly numbers on the POFs. Results show that when the anomaly number is 25, the differences between the POFs are less than 32.9%, and a 1.329 correction factor <span><math><mrow><msub><mi>z</mi><mi>P</mi></msub></mrow></math></span> is supposed to modify the POF. When the anomaly number is larger than 50, a 1.2 correction factor <span><math><mrow><msub><mi>z</mi><mi>P</mi></msub></mrow></math></span> is supposed to obtain the most conservative risk value with a 95% confidence level.</div></div>","PeriodicalId":51341,"journal":{"name":"Propulsion and Power Research","volume":"13 4","pages":"Pages 503-522"},"PeriodicalIF":5.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140280987","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.2024.07.001
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}
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