首页 > 最新文献

INCAS Bulletin最新文献

英文 中文
Magnetic Shielding Implementation in the Small Satellite Reaction Wheel 在小卫星反应轮中实施磁屏蔽
Q2 Engineering Pub Date : 2024-03-11 DOI: 10.13111/2066-8201.2024.16.1.11
Satriya Utama, Deddy El Amin, M. A. Saifudin, Moh. Farid Huzain, Widya Roza, C. T. Judianto, Mohammad Mukhayadi
Low Earth orbit satellites face challenges from Earth's magnetic field, causing attitude disturbances. Attaining a magnetic-dipole-free satellite is crucial. Layout optimization and in-orbit dipole compensation are common methods, but layout optimization can be impractical. In contrast, in-orbit dipole compensation struggles with rapidly changing magnetic dipoles like those from reaction wheel motors. This research proposes an alternative solution using Mu-metal, known for shielding against magnetic exposure. This shield can be applied to trap the magnetic field generated by the motors. Ground tests evaluated this approach. First, it determined the minimum distance between the magnetometer and the shield for accurate measurements with minimal interference, with the result of 10 cm as the least affected distance, particularly important for small satellite layout design. Second, it assessed the shield's effectiveness in trapping the motor-generated magnetic field. Tests showed a significant reduction in magnetic field magnitude and up to a 95% reduction in field fluctuations when the motor is activated. This research offers a practical solution for small satellite layout design, addressing the challenges posed by their compact dimensions. Mu-metal shielding proves effective for mitigating rapidly changing magnetic dipoles and enhancing magnetic cleanliness in low Earth orbit.
低地球轨道卫星面临着来自地球磁场的挑战,磁场会对卫星姿态造成干扰。实现无磁偶极子卫星至关重要。布局优化和在轨偶极子补偿是常用的方法,但布局优化可能不切实际。相比之下,在轨偶极子补偿则难以应对快速变化的磁偶极子,如反作用轮电机产生的磁偶极子。这项研究提出了一种使用缪金属(Mu-metal)的替代解决方案。这种屏蔽可用于捕捉电机产生的磁场。地面试验对这种方法进行了评估。首先,它确定了磁强计与屏蔽罩之间的最小距离,以便在干扰最小的情况下进行精确测量,结果发现 10 厘米是受影响最小的距离,这对小型卫星布局设计尤为重要。其次,它评估了屏蔽罩在捕获电机产生的磁场方面的有效性。测试表明,当电机启动时,磁场幅度明显减小,磁场波动减少达 95%。这项研究为小型卫星布局设计提供了一个实用的解决方案,解决了其紧凑尺寸带来的挑战。事实证明,μ金属屏蔽可有效缓解快速变化的磁偶极子,并提高低地球轨道的磁洁净度。
{"title":"Magnetic Shielding Implementation in the Small Satellite Reaction Wheel","authors":"Satriya Utama, Deddy El Amin, M. A. Saifudin, Moh. Farid Huzain, Widya Roza, C. T. Judianto, Mohammad Mukhayadi","doi":"10.13111/2066-8201.2024.16.1.11","DOIUrl":"https://doi.org/10.13111/2066-8201.2024.16.1.11","url":null,"abstract":"Low Earth orbit satellites face challenges from Earth's magnetic field, causing attitude disturbances. Attaining a magnetic-dipole-free satellite is crucial. Layout optimization and in-orbit dipole compensation are common methods, but layout optimization can be impractical. In contrast, in-orbit dipole compensation struggles with rapidly changing magnetic dipoles like those from reaction wheel motors. This research proposes an alternative solution using Mu-metal, known for shielding against magnetic exposure. This shield can be applied to trap the magnetic field generated by the motors. Ground tests evaluated this approach. First, it determined the minimum distance between the magnetometer and the shield for accurate measurements with minimal interference, with the result of 10 cm as the least affected distance, particularly important for small satellite layout design. Second, it assessed the shield's effectiveness in trapping the motor-generated magnetic field. Tests showed a significant reduction in magnetic field magnitude and up to a 95% reduction in field fluctuations when the motor is activated. This research offers a practical solution for small satellite layout design, addressing the challenges posed by their compact dimensions. Mu-metal shielding proves effective for mitigating rapidly changing magnetic dipoles and enhancing magnetic cleanliness in low Earth orbit.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140253154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Applying Proper Orthogonal Decomposition to Parabolic Equations: A Reduced Order Numerical Approach 将适当正交分解应用于抛物线方程:降阶数值方法
Q2 Engineering Pub Date : 2024-03-11 DOI: 10.13111/2066-8201.2024.16.1.7
Mircea Moraru
n this paper we present a low-order numerical scheme developed using the Proper Orthogonal (POD) method to address non-homogeneous parabolic equations in both one and two dimensions. The proposed schemes leverage the POD technique to reduce the computational complexity associated with solving these equations while maintaining accuracy. By employing POD, the high-dimensional problem is approximated by a reduced set of models, allowing for a more efficient representation of the system dynamics. The application of this method to non-homogenous parabolic equations offers a promising approach for enhancing the computational efficiency of simulations in diverse fields, such as fluid dynamics, heat conduction, and reaction-diffusion processes. The presented numerical scheme demonstrates its efficacy in achieving accurate results with significantly reduced computational costs, making it a valuable tool for applications demanding efficient solutions to non-homogeneous parabolic equations in one and two dimensions.
本文介绍了一种使用正交(POD)方法开发的低阶数值方案,用于求解一维和二维的非均质抛物方程。所提出的方案利用 POD 技术降低了求解这些方程的计算复杂度,同时保持了精度。通过使用 POD,高维问题可以用一组缩小的模型来近似,从而更有效地表示系统动态。将这种方法应用于非同质抛物方程,为提高流体动力学、热传导和反应扩散过程等不同领域的模拟计算效率提供了一种可行的方法。所提出的数值方案证明了其在获得精确结果的同时显著降低计算成本的功效,使其成为要求高效求解一维和二维非均质抛物方程的应用的重要工具。
{"title":"Applying Proper Orthogonal Decomposition to Parabolic Equations: A Reduced Order Numerical Approach","authors":"Mircea Moraru","doi":"10.13111/2066-8201.2024.16.1.7","DOIUrl":"https://doi.org/10.13111/2066-8201.2024.16.1.7","url":null,"abstract":"n this paper we present a low-order numerical scheme developed using the Proper Orthogonal (POD) method to address non-homogeneous parabolic equations in both one and two dimensions. The proposed schemes leverage the POD technique to reduce the computational complexity associated with solving these equations while maintaining accuracy. By employing POD, the high-dimensional problem is approximated by a reduced set of models, allowing for a more efficient representation of the system dynamics. The application of this method to non-homogenous parabolic equations offers a promising approach for enhancing the computational efficiency of simulations in diverse fields, such as fluid dynamics, heat conduction, and reaction-diffusion processes. The presented numerical scheme demonstrates its efficacy in achieving accurate results with significantly reduced computational costs, making it a valuable tool for applications demanding efficient solutions to non-homogeneous parabolic equations in one and two dimensions.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140253282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Enhancing UAV elevator actuator model using multibody dynamics simulation 利用多体动力学模拟改进无人飞行器升降推杆模型
Q2 Engineering Pub Date : 2024-03-11 DOI: 10.13111/2066-8201.2024.16.1.12
Akhmad Farid Widodo, F. S. Pranoto, I. E. Putro, E. D. Arisandi
This paper proposes an improved actuator system model for UAV elevators using multibody dynamics simulation. The multibody dynamics simulation employs the Simscape Multibody, module in MATLAB coupled with Simulink to model the servo and hinge moment calculation. The actuator system comprises an electrical servo and mechanical components, including arms, push rods, horns, and the elevator. The electrical servo is modeled using a PID controller and a simplified motor model. The multibody dynamics simulation is employed to capture the dynamics of the mechanical components, coupled with the electrical servo through torque delivery to the mechanical components. The simulation is applied to the elevator of a medium altitude long endurance (MALE) UAV with a Maximum Take Off Weight of 1300 Kg. Generating these quantities provide a benefit in capturing the operational envelope of the servo to be compared to its limitations. Given the features of this simulation, it is proposed to extend the research by integrating this method with flight dynamics simulation.
本文利用多体动力学仿真提出了一种改进的无人机升降机致动器系统模型。多体动力学仿真采用了 MATLAB 中的 Simscape 多体模块,并结合 Simulink 对伺服和铰链力矩计算进行建模。推杆系统由电气伺服和机械部件组成,包括臂、推杆、角和电梯。电气伺服系统使用 PID 控制器和简化的电机模型建模。多体动力学仿真用于捕捉机械部件的动态,并通过向机械部件传递扭矩与电气伺服系统进行耦合。模拟应用于最大起飞重量为 1300 千克的中空长航时(MALE)无人机的升降机。生成这些数据有利于捕捉伺服器的运行范围,并与其局限性进行比较。鉴于这种模拟的特点,建议将这种方法与飞行动力学模拟相结合,以扩展研究。
{"title":"Enhancing UAV elevator actuator model using multibody dynamics simulation","authors":"Akhmad Farid Widodo, F. S. Pranoto, I. E. Putro, E. D. Arisandi","doi":"10.13111/2066-8201.2024.16.1.12","DOIUrl":"https://doi.org/10.13111/2066-8201.2024.16.1.12","url":null,"abstract":"This paper proposes an improved actuator system model for UAV elevators using multibody dynamics simulation. The multibody dynamics simulation employs the Simscape Multibody, module in MATLAB coupled with Simulink to model the servo and hinge moment calculation. The actuator system comprises an electrical servo and mechanical components, including arms, push rods, horns, and the elevator. The electrical servo is modeled using a PID controller and a simplified motor model. The multibody dynamics simulation is employed to capture the dynamics of the mechanical components, coupled with the electrical servo through torque delivery to the mechanical components. The simulation is applied to the elevator of a medium altitude long endurance (MALE) UAV with a Maximum Take Off Weight of 1300 Kg. Generating these quantities provide a benefit in capturing the operational envelope of the servo to be compared to its limitations. Given the features of this simulation, it is proposed to extend the research by integrating this method with flight dynamics simulation.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140252672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
CFD modeling for urban blast simulation 用于城市爆炸模拟的 CFD 建模
Q2 Engineering Pub Date : 2024-03-11 DOI: 10.13111/2066-8201.2024.16.1.6
F. Marin, D. Buruiana, Viorica Ghisman, M. Marin
In this paper we present a Computational Fluid Dynamics (CFD) simulations for the case of natural gas explosion in urban area. Blast simulations aid in the development of effective mitigation strategies. By understanding how blast waves propagate through an urban environment, authorities can implement measures such as barriers, protective shields, strategies for firefighting strategy or evacuation plans to minimize damage and casualties. Accurate simulations provide insights into the potential impact of a blast on surrounding infrastructure and populations. This information is crucial for emergency response planning, helping authorities to allocate resources and respond effectively to minimize the consequences of an explosion.
本文介绍了针对城市地区天然气爆炸案例的计算流体动力学(CFD)模拟。爆炸模拟有助于制定有效的缓解策略。通过了解爆炸波如何在城市环境中传播,有关部门可以实施各种措施,如障碍物、防护罩、消防策略或疏散计划,以最大限度地减少损失和人员伤亡。准确的模拟可让人们深入了解爆炸对周围基础设施和人口的潜在影响。这些信息对应急响应规划至关重要,有助于当局分配资源和有效应对,最大限度地减少爆炸的后果。
{"title":"CFD modeling for urban blast simulation","authors":"F. Marin, D. Buruiana, Viorica Ghisman, M. Marin","doi":"10.13111/2066-8201.2024.16.1.6","DOIUrl":"https://doi.org/10.13111/2066-8201.2024.16.1.6","url":null,"abstract":"In this paper we present a Computational Fluid Dynamics (CFD) simulations for the case of natural gas explosion in urban area. Blast simulations aid in the development of effective mitigation strategies. By understanding how blast waves propagate through an urban environment, authorities can implement measures such as barriers, protective shields, strategies for firefighting strategy or evacuation plans to minimize damage and casualties. Accurate simulations provide insights into the potential impact of a blast on surrounding infrastructure and populations. This information is crucial for emergency response planning, helping authorities to allocate resources and respond effectively to minimize the consequences of an explosion.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140252683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Identification of roll damping coefficient using the free rotation method 利用自由旋转法确定滚动阻尼系数
Q2 Engineering Pub Date : 2024-03-11 DOI: 10.13111/2066-8201.2024.16.1.2
Ionuț Bunescu, Mihai-Victor Pricop, M. Stoican, Mihai-Vlăduţ Hothazie
The free rotation method represents the simplest method for roll damping coefficient identification in experimental aerodynamics. To apply this method, it is necessary to spin the model to a desired angular velocity and then release the model to spin freely under flow conditions, recording the variation in time of the model’s rolling rate. Thus, applying the logarithmic decrement formula at any roll rate between near zero and the desired angular velocity, the roll damping moment will be calculated. This paper presents the application of the free rotation method on raw data obtained for different Mach numbers and incidences, considering different regression functions, time windows and their implications. Last but not least, the necessary correction methods and their impact on the results are presented.
自由旋转法是空气动力学实验中确定滚动阻尼系数的最简单方法。应用这种方法时,需要将模型旋转到所需的角速度,然后释放模型,使其在流动条件下自由旋转,并记录模型滚动率的时间变化。这样,在接近零和所需角速度之间的任何滚动率上应用对数递减公式,就可以计算出滚动阻尼力矩。本文介绍了自由旋转方法在不同马赫数和发生率下获得的原始数据上的应用,并考虑了不同的回归函数、时间窗口及其影响。最后还介绍了必要的修正方法及其对结果的影响。
{"title":"Identification of roll damping coefficient using the free rotation method","authors":"Ionuț Bunescu, Mihai-Victor Pricop, M. Stoican, Mihai-Vlăduţ Hothazie","doi":"10.13111/2066-8201.2024.16.1.2","DOIUrl":"https://doi.org/10.13111/2066-8201.2024.16.1.2","url":null,"abstract":"The free rotation method represents the simplest method for roll damping coefficient identification in experimental aerodynamics. To apply this method, it is necessary to spin the model to a desired angular velocity and then release the model to spin freely under flow conditions, recording the variation in time of the model’s rolling rate. Thus, applying the logarithmic decrement formula at any roll rate between near zero and the desired angular velocity, the roll damping moment will be calculated. This paper presents the application of the free rotation method on raw data obtained for different Mach numbers and incidences, considering different regression functions, time windows and their implications. Last but not least, the necessary correction methods and their impact on the results are presented.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140252532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Noise silencer design using triply periodic minimal surfaces 利用三重周期性最小表面进行消音设计
Q2 Engineering Pub Date : 2024-03-11 DOI: 10.13111/2066-8201.2024.16.1.10
Andrei Totu, Cristian-Teodor Olariu, Andreea-Catalina Totu, Andrei-Tudor Trifu
Noise reduction is a problem of great global interest, as we are surrounded by machines that produce noise emissions in one way or another. The 20th century saw the start of a strong development in noise reduction methods, with different methods being developed over the years, but the greatest advances in their application have been seen in recent decades. The proposed solution aims to solve the limitations of classic noise attenuators by combining two effects, destructive interference and Helmholtz resonator, and introducing a slightly atypical geometry compared to classic designs. The proposed geometry was mathematically defined a long time ago, but in recent years it has become of great interest in various fields, from CO2 capture to heat exchangers.
降噪是一个备受全球关注的问题,因为我们周围的机器或多或少都会产生噪音。20 世纪,降噪方法开始得到大力发展,多年来开发出了各种不同的方法,但其应用方面的最大进步出现在最近几十年。所提出的解决方案旨在结合破坏性干扰和亥姆霍兹谐振器这两种效应,并引入一种与经典设计相比略显非典型的几何形状,从而解决经典噪声衰减器的局限性。所提出的几何形状很早就在数学上定义好了,但近年来,从二氧化碳捕获到热交换器等各个领域都对它产生了浓厚的兴趣。
{"title":"Noise silencer design using triply periodic minimal surfaces","authors":"Andrei Totu, Cristian-Teodor Olariu, Andreea-Catalina Totu, Andrei-Tudor Trifu","doi":"10.13111/2066-8201.2024.16.1.10","DOIUrl":"https://doi.org/10.13111/2066-8201.2024.16.1.10","url":null,"abstract":"Noise reduction is a problem of great global interest, as we are surrounded by machines that produce noise emissions in one way or another. The 20th century saw the start of a strong development in noise reduction methods, with different methods being developed over the years, but the greatest advances in their application have been seen in recent decades. The proposed solution aims to solve the limitations of classic noise attenuators by combining two effects, destructive interference and Helmholtz resonator, and introducing a slightly atypical geometry compared to classic designs. The proposed geometry was mathematically defined a long time ago, but in recent years it has become of great interest in various fields, from CO2 capture to heat exchangers.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140252301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The quantum states for Hydrogen atom: spherical harmonics and the orbitals geometrical representation 氢原子的量子态:球谐波和轨道几何表示法
Q2 Engineering Pub Date : 2024-03-11 DOI: 10.13111/2066-8201.2024.16.1.3
D. Constantin, L. Preda, A. A. Mocanu, D. Popescu, D. Pricopi, V. I. Niculescu
Our work utilizes the quantum model of the hydrogen atom which is based on the Schrödinger equation with Coulomb potential. Specifically, we concentrate on the angular components of the wave eigenfunctions derived from this model. We consider the quantum states with n ≤ 4. In order to visualize the orbital shapes of these states, we built in the spherical coordinates system their 3D geometric representations. Furthermore, we use the corresponding spherical harmonics, to calculate the θ nodal values that describe the configurations of these orbital states.
我们的研究利用了基于库仑势的薛定谔方程的氢原子量子模型。具体来说,我们专注于从该模型推导出的波特征函数的角分量。我们考虑 n ≤ 4 的量子态。为了直观地显示这些状态的轨道形状,我们在球坐标系中建立了它们的三维几何表示。此外,我们还利用相应的球面谐波来计算描述这些轨道态构型的 θ 节点值。
{"title":"The quantum states for Hydrogen atom: spherical harmonics and the orbitals geometrical representation","authors":"D. Constantin, L. Preda, A. A. Mocanu, D. Popescu, D. Pricopi, V. I. Niculescu","doi":"10.13111/2066-8201.2024.16.1.3","DOIUrl":"https://doi.org/10.13111/2066-8201.2024.16.1.3","url":null,"abstract":"Our work utilizes the quantum model of the hydrogen atom which is based on the Schrödinger equation with Coulomb potential. Specifically, we concentrate on the angular components of the wave eigenfunctions derived from this model. We consider the quantum states with n ≤ 4. In order to visualize the orbital shapes of these states, we built in the spherical coordinates system their 3D geometric representations. Furthermore, we use the corresponding spherical harmonics, to calculate the θ nodal values that describe the configurations of these orbital states.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140253899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Numerical Analysis of a Supercritical Heat Transfer of Cryogenic Methane in Regeneratively Cooled Rocket Engine 再生冷却火箭发动机中低温甲烷超临界传热的数值分析
Q2 Engineering Pub Date : 2024-03-11 DOI: 10.13111/2066-8201.2024.16.1.4
Mohammed Amine Djeffal, N. Benamara, Abdelkader Lahcene, Ali Benouar, A. Boulenouar, Mohammed Merzoug
A comparative study of supercritical heat transfer in a regeneratively cooled rocket engine was conducted using three-dimensional numerical simulations for two channel geometries: rectangular and square. Various constant heat fluxes, flow velocities, and operating pressures were imposed to study their effect on heat transfer, pressure losses, and the conditions under which heat transfer deterioration HTD occurs. The results show that a rectangular channel is more efficient in terms of heat transfer than a square channel, with a more pronounced difference at high heat fluxes and low velocities, these conditions, in fact, favored the occurrence of heat transfer deterioration, particularly in the square channel. Increasing the flow velocities to reduce the wall temperature and prevent thermal deterioration was accompanied by a significant increase in pressure losses, these pressure losses are greater in the rectangular channel, despite its advantages in terms of heat transfer. Operating pressure also plays an important role in heat transfer, increasing the pressure results in a decrease in wall temperature.
通过对矩形和方形两种通道几何形状的三维数值模拟,对再生冷却火箭发动机中的超临界传热进行了比较研究。通过施加不同的恒定热通量、流速和工作压力,研究了它们对传热、压力损失以及传热恶化 HTD 发生条件的影响。结果表明,矩形水道的传热效率高于方形水道,在高热流量和低流速条件下,两者的差异更为明显。提高流速以降低壁温并防止热退化的同时,压力损失也显著增加,尽管矩形水道在传热方面具有优势,但压力损失在矩形水道中更大。工作压力在热传递中也起着重要作用,增加压力会导致壁温降低。
{"title":"Numerical Analysis of a Supercritical Heat Transfer of Cryogenic Methane in Regeneratively Cooled Rocket Engine","authors":"Mohammed Amine Djeffal, N. Benamara, Abdelkader Lahcene, Ali Benouar, A. Boulenouar, Mohammed Merzoug","doi":"10.13111/2066-8201.2024.16.1.4","DOIUrl":"https://doi.org/10.13111/2066-8201.2024.16.1.4","url":null,"abstract":"A comparative study of supercritical heat transfer in a regeneratively cooled rocket engine was conducted using three-dimensional numerical simulations for two channel geometries: rectangular and square. Various constant heat fluxes, flow velocities, and operating pressures were imposed to study their effect on heat transfer, pressure losses, and the conditions under which heat transfer deterioration HTD occurs. The results show that a rectangular channel is more efficient in terms of heat transfer than a square channel, with a more pronounced difference at high heat fluxes and low velocities, these conditions, in fact, favored the occurrence of heat transfer deterioration, particularly in the square channel. Increasing the flow velocities to reduce the wall temperature and prevent thermal deterioration was accompanied by a significant increase in pressure losses, these pressure losses are greater in the rectangular channel, despite its advantages in terms of heat transfer. Operating pressure also plays an important role in heat transfer, increasing the pressure results in a decrease in wall temperature.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140252601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The impact of the Laval nozzle shape on thrust production, using the method of characteristics 拉瓦尔喷嘴形状对推力产生的影响,使用特征法
Q2 Engineering Pub Date : 2024-03-11 DOI: 10.13111/2066-8201.2024.16.1.8
A. -. I. Paraschiv
This investigation examines the influence of Laval nozzle geometry on thrust production using the method of characteristics. It explores various divergent section configurations, analyzing their impact on nozzle design and performance. Comparative analysis of software tools, study of supersonic flow phenomena, and application of the method of characteristics form the core of this research. Findings showcase strong agreement between computational tools, emphasizing the Mach number's role in divergent section shape variations and thrust force. Additionally, the study scrutinizes over-expansion and under-expansion phenomena, validated through computational simulations. Future research should be aimed at enhancing computational methodologies and investigating additional parameters affecting nozzle performance, promising advancements in rocket propulsion technology.
本研究采用特征法研究了拉瓦尔喷嘴几何形状对推力产生的影响。它探索了各种发散截面配置,分析了它们对喷嘴设计和性能的影响。软件工具的比较分析、超音速流动现象的研究以及特性法的应用构成了本研究的核心。研究结果表明计算工具之间具有很强的一致性,强调了马赫数在发散截面形状变化和推力中的作用。此外,该研究还通过计算模拟验证了过度膨胀和膨胀不足现象。未来的研究应着眼于加强计算方法和调查影响喷嘴性能的其他参数,从而有望推动火箭推进技术的进步。
{"title":"The impact of the Laval nozzle shape on thrust production, using the method of characteristics","authors":"A. -. I. Paraschiv","doi":"10.13111/2066-8201.2024.16.1.8","DOIUrl":"https://doi.org/10.13111/2066-8201.2024.16.1.8","url":null,"abstract":"This investigation examines the influence of Laval nozzle geometry on thrust production using the method of characteristics. It explores various divergent section configurations, analyzing their impact on nozzle design and performance. Comparative analysis of software tools, study of supersonic flow phenomena, and application of the method of characteristics form the core of this research. Findings showcase strong agreement between computational tools, emphasizing the Mach number's role in divergent section shape variations and thrust force. Additionally, the study scrutinizes over-expansion and under-expansion phenomena, validated through computational simulations. Future research should be aimed at enhancing computational methodologies and investigating additional parameters affecting nozzle performance, promising advancements in rocket propulsion technology.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140253611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The Euler’s harmonic holomorphic regenerative universe 欧拉谐波全形再生宇宙
Q2 Engineering Pub Date : 2024-03-11 DOI: 10.13111/2066-8201.2024.16.1.5
H. Dumitrescu, V. Cardoş, Radu Bogateanu
The Cartesian dualism is a precursor to Euler’s complex theory, that completes the Descartes-Leibnitz monadic conception using the natural quanta (non-splitting e, π) along with their topological torsion in the form of dual isomorphism. The complete Euler’s identity controls a bounded regenerative/ recurrent multiverse (a kind of multigraph) by two regenerative exponential functions, one quantic, e = exp (1) and another gravitational, g0 ≡ 10 = exp (1) with the fixed points, g0 = π2 and (g0g0) respectively. Physically, the fixed points give the well-defined the unit gravity (g0 m/s2) and light self-ignition velocity of a stable recurrent self-sustained process, provided the rate of mass production just equals the rate removal. This is the Euler’s fictitious regenerative universe - like our world, a quantum autocatalytic reaction system. The present paper describes such a system controlled by thermal gravitational waves, in the case the critical solar system.
笛卡尔二元论是欧拉复数理论的前身,它利用自然量子(非分裂的 e、π)及其拓扑扭转,以对偶同构的形式完成了笛卡尔-莱布尼茨一元论概念。完整的欧拉同一性通过两个再生指数函数(一个量子函数,e = exp (1),另一个引力函数,g0 ≡ 10 = exp (1))控制一个有界再生/循环多重宇宙(一种多重图),这两个函数的定点分别是 g0 = π2 和 (g0g0)。从物理学角度看,只要质量生产率刚好等于清除率,这些定点就给出了一个稳定的循环自持过程的单位重力(g0 m/s2)和光自燃速度的明确定义。这就是欧拉虚构的再生宇宙--就像我们的世界一样,一个量子自催化反应系统。本文以临界太阳系为例,描述了这样一个由热引力波控制的系统。
{"title":"The Euler’s harmonic holomorphic regenerative universe","authors":"H. Dumitrescu, V. Cardoş, Radu Bogateanu","doi":"10.13111/2066-8201.2024.16.1.5","DOIUrl":"https://doi.org/10.13111/2066-8201.2024.16.1.5","url":null,"abstract":"The Cartesian dualism is a precursor to Euler’s complex theory, that completes the Descartes-Leibnitz monadic conception using the natural quanta (non-splitting e, π) along with their topological torsion in the form of dual isomorphism. The complete Euler’s identity controls a bounded regenerative/ recurrent multiverse (a kind of multigraph) by two regenerative exponential functions, one quantic, e = exp (1) and another gravitational, g0 ≡ 10 = exp (1) with the fixed points, g0 = π2 and (g0g0) respectively. Physically, the fixed points give the well-defined the unit gravity (g0 m/s2) and light self-ignition velocity of a stable recurrent self-sustained process, provided the rate of mass production just equals the rate removal. This is the Euler’s fictitious regenerative universe - like our world, a quantum autocatalytic reaction system. The present paper describes such a system controlled by thermal gravitational waves, in the case the critical solar system.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140251976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
INCAS Bulletin
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1