{"title":"Gravity Unloading Method of Membrane Phased-array Antennas Using Electrostatic Adsorption","authors":"Wang Zhong, Jichuan Xiong, Yiqun Zhang","doi":"10.1007/s12217-023-10083-8","DOIUrl":"10.1007/s12217-023-10083-8","url":null,"abstract":"<div><p>In this study, a gravity unloading method based on electrostatic adsorption is proposed to address the issue of large flexibility in membrane phased-array antennas. Through considering the gravity distribution of the antenna and the edge effect of the electrode system, the unloading efficiency and system robustness are improved using a grouping strategy and size optimization. The deformation equilibrium equation under both gravity and electrostatic fields is established, and the voltage optimization model of the electrode system is also formulated with the goal of complete compensation for gravity deformation. The advantages and effectiveness of the proposed method are demonstrated by comparing simulation and unloading experiment results with those obtained using the suspension method. Both results indicate that the electrostatic unloading method can achieve the same unloading effect as the suspension method. Moreover, without introducing in-plane deformations during unloading, this method enhances accuracy and provides valuable insights for optimizing the assembly and testing processes.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"35 6","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138431578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shuai Wang, Xiang Ma, Quan Gao, Jinyu Wang, Na Xu, Yonghai Zhang, Jinjia Wei, Jianfu Zhao, Bin Li
{"title":"Preparation and Performance Characterization of Copper and Diamond Filled Composite Thermal Conductivity Materials","authors":"Shuai Wang, Xiang Ma, Quan Gao, Jinyu Wang, Na Xu, Yonghai Zhang, Jinjia Wei, Jianfu Zhao, Bin Li","doi":"10.1007/s12217-023-10082-9","DOIUrl":"10.1007/s12217-023-10082-9","url":null,"abstract":"<div><p>An experimental investigation was conducted to prepare and study the thermal conductivity performance of copper and diamond composite materials. Copper powder and diamond particles were used as fillers, epoxy resin was used as matrix, and composite materials were prepared by vacuum-assisted mechanical stirring. The thermal expansion coefficient of different composite materials was measured by a laser flash method, which can be used to calculate the thermal conductivity. The effect of the filling rate of copper powder, the morphology of copper powder, the filling rate of diamond, and the thermal conductivity of the particles on the thermal conductivity of composite materials was studied. The results showed that thermal conductivity of copper powder and diamond particles composite materials were 874% and 535% higher than that of the epoxy resin when their filling rates were 50.3 vol.% and 40.0 vol.%, respectively. For two-dimensional flake copper powder materials, the thermal conductivity could be effectively improved at a lower filling rate. However, the flake particles were easy to aggregate at a high filling rate, which maybe cause the composite materials to pulverize.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"35 6","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134797010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Research on the Driving Simulation Method of a Manned Lunar Rover System for Somatosensory Representation","authors":"Qihang Yu, Dianliang Wu, Shunzhou Huang, Hanzhong Xu, Yue Zhao, Huanchong Cheng","doi":"10.1007/s12217-023-10078-5","DOIUrl":"10.1007/s12217-023-10078-5","url":null,"abstract":"<div><p>During the lunar surface activities of the manned lunar landing project, the design verification and driving training of the manned lunar rover system should be carried out according to the requirements of space mission verification and astronaut comprehensive operation training. In this case, it is difficult to conduct somatosensory simulation of human rover driving training in the lunar surface environment. To solve the above problems, first, the characteristics of astronaut motion sensing information reception were analyzed, the lunar surface environment was created in the virtual environment, the lunar gravity conditions were established, and the dynamics model of the man-vehicle-moon system was established for motion sensing simulation. Then, the parameters of the somatosensory model are provided by dynamics calculation, and the astronaut's attitude adjustment is considered to simulate and verify the somatosensory model. Finally, the motion characteristics of astronauts driving on the Moon are analyzed, which provides support for the design verification and driving operation training of manned lunar rovers.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"35 6","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12217-023-10078-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134795502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rada Novakovic, Donatella Giuranno, Markus Mohr, Hans-Jöerg Fecht
{"title":"Thermodynamic Evaluation of the Surface Tension and Viscosity of Liquid Quaternary Alloys: The Ti-Al-Cr-Nb System","authors":"Rada Novakovic, Donatella Giuranno, Markus Mohr, Hans-Jöerg Fecht","doi":"10.1007/s12217-023-10080-x","DOIUrl":"10.1007/s12217-023-10080-x","url":null,"abstract":"<div><p>Surface tension and viscosity of complex Ti-based industrial alloys are important for simulation of liquid assisted industrial processes such as casting, joining, crystal growth and infiltration. Modelling of the interface and mass transport during liquid-solid phase transition requires reliable surface tension and viscosity data. Therefore, to obtain accurate predictions of microstructural evolution during solidification related processes, only reliable input data are necessary. In the case of liquid Ti-Al alloys, the experimental difficulties related to high temperature measurements and reactivity of these alloys with supporting materials or containers as well as inevitable presence of oxygen may lead to data gaps including a complete lack of property data. An alternative for container-based methods are containerless processing techniques that offer a significant accuracy improvement and / or make possible to measure temperature and composition dependent thermophysical properties of metallic melts, as in the case of the Ti-Al-Cr-Nb system. Advanced mathematical models and computer simulations, developed in several theoretical frameworks, can be used to compensate the missing data; on the other side, for the validation of theoretical models, the experimental data are used. In the present work, an evaluation of the surface tension and viscosity of liquid Ti-Al-Cr-Nb alloys by means of the predictive models and a comparison to the available experimental data were done. The proposed methodology is a tool to assess the reliability of thermophysical properties data of multicomponent alloy systems.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"35 6","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12217-023-10080-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134797507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comment on the Paper Numerical Simulation for Magneto Nanofluid Flow Through a Porous Space with Melting Heat Transfer, T. Hayat, Faisal Shah, A. Alsaedi, M. Waqas, Microgravity Science and Technology (2018) 30:265–275","authors":"Asterios Pantokratoras","doi":"10.1007/s12217-023-10079-4","DOIUrl":"10.1007/s12217-023-10079-4","url":null,"abstract":"<div><p>Some serious errors exist in the above paper. Many concentration profiles are truncated and wrong. The local similarity method used is not correct. The dimensionless Hartmann number is dimensional and wrong.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"35 6","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12217-023-10079-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50497954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jordan Eaton, Juan D. Carvajal-Agudelo, Tamara A. Franz-Odendaal
{"title":"Comparison of Effects of 2D and 3D Simulated Microgravity Rotation on Ossification in Larval Danio Rerio (Zebrafish)","authors":"Jordan Eaton, Juan D. Carvajal-Agudelo, Tamara A. Franz-Odendaal","doi":"10.1007/s12217-023-10077-6","DOIUrl":"10.1007/s12217-023-10077-6","url":null,"abstract":"<div><p>Simulated microgravity (SMG) is an environmental condition that affects bone density in vertebrates. Ground-based studies typically use a random positioning machine in either a 2D or a 3D mode to assess the effects of SMG, however the meaning of these results is difficult to compare between studies due to different experimental parameters. Here, we exposed larval <i>Danio rerio</i> at 3dpf to 23 h of SMG using a 2D and a 3D mode of rotation, using the same experimental setup. Zebrafish larvae were anaesthetized during the experiment. Our results showed that anesthesia (MS222) did not affect the amount of ossification while SMG-2D treatment slightly reduced the amount of ossification compared with the controls. On the other hand, SMG-3D treatment significantly reduced the overall ossification level of the skeleton. Specifically, the anterior end of the notochord, the ceratobranchial-5, the lower jaw articulation, the pharyngeal teeth, and the operculum were affected compared with control treatments. Overall, these results indicate that SMG-3D produced a more effective SMG effect compared with the SMG-2D. This research provides valuable insight into how different external stimuli such as SMG can cause negative effects on ossification in the developing skeleton in zebrafish.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"35 5","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134796230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Performance Assessment Framework for Multirotor Unmanned Aerial Vehicle Microgravity Platforms","authors":"Siddhardha Kedarisetty, Joel George Manathara","doi":"10.1007/s12217-023-10074-9","DOIUrl":"10.1007/s12217-023-10074-9","url":null,"abstract":"<div><p>This paper presents a method to analyse multirotor unmanned aerial vehicles (MUAVs) as microgravity platforms. MUAVs can maintain a free-fall state and provide microgravity owing to their precise thrust control abilities. Moreover, MUAVs are affordable platforms that can be procured at low-cost. Although several MUAVs of various sizes and configurations exist, their capabilities as microgravity platforms are not readily available. Towards this, a framework is developed to estimate microgravity performance measures such as 0<i>g</i>-time, payload capacity, and 0<i>g</i>-quality for a given MUAV. The proposed estimation framework requires only the data provided by the MUAV manufacturer to compute all the microgravity performance measures. The performance as a microgravity platform of several existing MUAVs of various configurations, masses, sizes, and thrust capabilities is estimated by employing this framework. This analysis reveals that there exist MUAVs that can provide microgravity (of the order of <span>(10^{-2}g)</span>) for more than 4 s 0<i>g</i>-time while carrying more than 1 kg payloads. On the other hand, it is also shown that some MUAVs can carry payloads heavier than 90 kgs and provide microgravity for 2 s, which is comparable to the capability of some of the drop tower facilities.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"35 5","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134797785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Thermocapillary Convection of Evaporating Thin Nanofluid Layer in a Rectangular Cavity","authors":"Yuequn Tao, Qiusheng Liu, Jun Qin, Zhiqiang Zhu","doi":"10.1007/s12217-023-10076-7","DOIUrl":"10.1007/s12217-023-10076-7","url":null,"abstract":"<div><p>Thermocapillary convection of nanofluid with evaporating phase change interface occurs in a variety of industrial processes such as micro/nano fabrication, ink-jet printing, thin film coatings, etc. Previous studies have mostly focused on the phenomena of thermocapillary convection in pure fluids without phase change. This paper reports the first fundamental experimental work on the thermocapillary flow of a thin nanofluid layer under the effect of evaporation. This research focuses on the behavior of a volatile thin nanofluid layer in a rectangular test cell under the effects of horizontal temperature gradient. The buoyancy effect can be neglected inside this thin liquid layer as in microgravity conditions. HEE7200 and HFE7200-Al<sub>2</sub>O<sub>3</sub> nanofluid are used as working fluids to analyze the effect of nanoparticle addition. The results indicate that the linear relationship between the thickness of the liquid layer and the duration of evaporation is not changed by nanoparticles. HFE7200-Al<sub>2</sub>O<sub>3</sub> nanofluid always has a higher evaporation rate than its base fluid with the temperature ranging from 2.98 °C to 13.92 °C. The critical Marangoni number for the nanofluid is lower than that of the pure fluid, which indicates that the addition of nanoparticles promotes the flow pattern transition.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"35 5","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134797442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Numerical Investigation on the Effects of InSb Geometry on the InGaSb Crystal Growth Under Microgravity","authors":"Xin Jin, Sheng Xu, Bing Wang, Zhanjun Chen","doi":"10.1007/s12217-023-10072-x","DOIUrl":"10.1007/s12217-023-10072-x","url":null,"abstract":"<div><p>In<sub>x</sub>Ga<sub>1−x</sub>Sb single crystals have been grown by using a GaSb/InSb/GaSb-sandwich system onboard at the International Space Station (ISS) via vertical gradient freezing method (VGF). In order to investigate the effects of InSb geometry on the InGaSb crystal growth under microgravity and further optimize the future space experiment, two-dimensional axisymmetric numerical simulations were carried out with different thicknesses and diameters of the InSb crystals. Simulation results showed that enough solutes from feed through diffusion is necessary for the crystal growth process and the InSb thickness will affect the axial Ga concentration gradient and therefore affect the crystal growth rates under microgravity. In addition, results also showed that a larger diameter for the InSb crystal will increase the volume crystal growth rates with a flatter shape for the grown crystal interfaces. In summary, simulation suggests a 2 mm or 3 mm thickness and a 12 mm diameter as the geometry of InSb for future space experiments.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"35 5","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134796978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}