Microgravity Science and Technology最新文献

{"title":"Profiles of free Surfaces in Revolved Containers Under Microgravity","authors":"Shuyang Chen,&nbsp;Li Duan,&nbsp;Wen Li,&nbsp;Shangtong Chen,&nbsp;Qi Kang","doi":"10.1007/s12217-023-10093-6","DOIUrl":"10.1007/s12217-023-10093-6","url":null,"abstract":"<div><p>Nowadays a propellant residual gauging method based on the thermal response of the tanks’ wall is developed. And the liquid distribution and meniscus height have great effects on the thermal response. Profiles of liquid free surfaces in revolved containers under microgravity are studied through theoretical analysis and numerical simulation in this paper. The analytical formula for the static profile of the liquid surface in the spherical tank is established. It shows that the profile is a section of a circle cut off by the tank wall. For given the geometry of the tank, liquid volume and contact angle, the profile of the free surfaces under microgravity can be obtained by using the Shooting method based on the theoretical model. Numerical simulation is carried out with the Volume of Fluid method, and it is verified that the static profiles at different contact angles and liquid filling rates fit the theoretical descriptions. It is concluded that the meniscus height increases slowly as the filling rate increases, and the smaller the contact angle, the more obvious this trend. Then the theory is extended to the tanks of arbitrary shapes, and the critical position of the profile is derived. Below the critical position the propellant may accumulate in some corners or pits, which makes it unable to be fully utilized. The critical position is related to the shape of the tank and the contact angle. This research is of great value for the prediction of the static profiles of liquid surfaces in tanks and the propellant residual gauging.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"36 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139751666","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":"Stability of One-Dimensional Vertical Flow Through a Porous Domain Under Pumping of a Finite Volume of Impurity","authors":"Boris S. Maryshev,&nbsp;Lyudmila S. Klimenko,&nbsp;Nikolay V. Kolchanov","doi":"10.1007/s12217-023-10089-2","DOIUrl":"10.1007/s12217-023-10089-2","url":null,"abstract":"<div><p>The problem of stability of one-dimensional filtration flow in a rectangular domain of porous medium is solved. The flow occurs when a portion of impurity is transported through the region against gravity. It is shown that the instability has an absolute character. A Rayleigh-Taylor instability is observed at the backward front of the concentration pulse. In this case, the observation time is always less than the passage time of the pulse through the domain. A theoretical model is proposed to describe this phenomenon taking into account immobilization and clogging. The influence of the problem parameters on the characteristic time of instability onset is investigated. Comparison of computational results with experimental data has shown the appropriateness of the chosen model. The ways of increasing this time are analyzed. It is shown that only one way to increase the instability time is to significantly reduce the buoyancy force impact. The latter force can be diminish by alteration of the gravity force.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"36 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139751914","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":"Dissipation Behaviors of Vibrated Granular Balls in Different Gravity Environments","authors":"Kai Zhang,&nbsp;Meng Chen,&nbsp;Farong Kou,&nbsp;Wenzhe Li","doi":"10.1007/s12217-024-10097-w","DOIUrl":"10.1007/s12217-024-10097-w","url":null,"abstract":"<div><p>The dissipation behavior of granular balls in a quasi-2D closed container subjected to vertical vibration is studied by means of discrete element method in this paper. Four universal granular phases playing high damping effect are finalized by simulating the gravity environments of Earth, Mars and Moon, respectively. Based on the commonality of dense granular clusters in the four high damping granular phases, the ideal dissipation behavior of granular balls in the quasi-2D closed container is indicated. Moreover, the optimal damping mechanism of granular balls in the quasi-2D vibrated closed container is further revealed by analyzing the differences of kinetic energy and potential energy of vibrated granular balls in the three different gravity environments. This study lays a foundation for maximizing the damping effect of vibrated granular materials with constant mass by controlling their dissipation behavior, which provides a new idea for the universal design of granular damping structures in engineering practice.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"36 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139553976","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":"Phase Separation through Screen Channel Liquid Acquisition Devices in Microgravity","authors":"Prithvi Shukla,&nbsp;Michael E. Dreyer","doi":"10.1007/s12217-023-10085-6","DOIUrl":"10.1007/s12217-023-10085-6","url":null,"abstract":"<div><p>To enable future deep space exploration, orbital refueling of spacecraft is essential. However, transferring liquid in a microgravity environment is a complex process dependent on various factors. One of the basic and critical tasks is to separate phases to allow the supply of gas-free liquid from one tank to another. For this purpose, a liquid acquisition device is essential. In this work, a screen channel liquid acquisition device was designed and used to investigate phase separation and liquid removal from an experiment tank in a microgravity environment. The experiments were performed using the drop tower facility at the University of Bremen, with HFE-7500 as the test liquid under isothermal conditions. This investigation explored the interdependent effects of various phenomena, including the reorientation of liquid in the tank, capillary rise between parallel plates, flow through screen pressure variation, and bubble point breakthrough. Under subcritical conditions, the SC-LAD was found to supply gas-free liquid at the outlet, as long as the pressure drop across the screen was lower than the bubble point threshold. At the critical point, the screen started to ingest bubbles, resulting in a sharp peak in the differential pressure signal. The wetted area of the screen was obtained by analyzing images captured with a high-speed camera and used to calculate the analytical pressure drop. The experimental results were compared with the analytical solution and discussed in detail.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"36 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12217-023-10085-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554051","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":"Collision Behaviors of Two Successive Compound Droplets in an Abrupt Expansion Microchannel","authors":"Nang X. Ho,&nbsp;Hung V. Vu,&nbsp;Truong V. Vu","doi":"10.1007/s12217-023-10095-4","DOIUrl":"10.1007/s12217-023-10095-4","url":null,"abstract":"<div><p>In the present paper, merging of two successive compound droplets in an abrupt expansion microchannel using direct numerical simulations is presented. The compound droplets undergo deformation and velocity decreases when entering the expansion region. Their interaction behaviors are divided into two modes of merging and non-merging. These two modes are dominated, and influenced by fluid dynamic parameters, compound droplets’ center distance, the expansion ratio of microchannels and the size of compound droplets, which are analyzed through the results of numerical simulation. The capillary number, the fluid viscosity, and the droplets’ distance increase lead to the merging time of the droplets increases. Although increasing the inner interfacial tension does not significantly affect the merging time of two outer droplets, it significantly reduces the merging time of two inner droplets. Meanwhile, varying the expansion ratio and the droplet size results in the transition between the two interaction modes. Two diagrams for the mode transition, based on the capillary number, the droplet center separation, and the droplet size are also given.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"36 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139510329","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":"Effect of Gravity Orientation on Flickering Characteristics of Premixed Conical Flame","authors":"Chenghao Qian,&nbsp;Yao Yang,&nbsp;Gaofeng Wang,&nbsp;Anastasia Krikunova,&nbsp;Keqi Hu","doi":"10.1007/s12217-023-10088-3","DOIUrl":"10.1007/s12217-023-10088-3","url":null,"abstract":"<div><p>Experimental and numerical simulation methods were employed to investigate the effect of gravity orientation on the dynamics of premixed conical flames. The study focused on a typical propane-air flame established on a Bunsen burner, under normal gravity (+ g), reverse gravity (-g), and transverse gravity (⊥g). In the initial phase of the research, flame shapes were examined using flame chemiluminescence imaging. Result shows that gravity orientation has a slight impact on the flame height, and buoyancy caused flame asymmetry in ⊥g case is first discovered. In addition, flame flickering frequencies were collected through heat release signal experiments, and a wide range of data is acquired. Though being affected by the same pattern by equivalence ratio and Reynolds number, the frequencies in ⊥g case are generally lower than those in + g case. Based on this, the research also obtained the new empirical correlation for ⊥g case. For clearer explanations of the flame behavior under different gravity orientations, velocity fields were visualization using Particle Image Velocimetry (PIV) experiments and Direct Numerical Simulation (DNS). Results indicated that the gravity orientation mainly influences the flame through effects on shear layer between ambient air and burnt gas, which cause different forms of K-H instability and vortex shedding motions.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"36 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139061329","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 Study on Pilot Ignition of a Thermally-Thick Solid Fuel with Low-Velocity Airflow in Microgravity","authors":"Kai Zhang,&nbsp;Feng Zhu,&nbsp;Shuangfeng Wang","doi":"10.1007/s12217-023-10092-7","DOIUrl":"10.1007/s12217-023-10092-7","url":null,"abstract":"<div><p>The mechanisms controlling the dependence on low-velocity flow of the piloted ignition of a solid material under external radiant heating is investigated through a numerical modeling. The poly (methyl methacrylate) (PMMA) was used as the fuel. The objective of the present study is to gain insight into the intrinsic ignition mechanisms of a solid fuel, as well as to gain a more comprehensive understanding of the dynamical characteristics of the ignition process near the extinction limit. For this purpose, a two-dimensional numerical model has been developed using the Fire Dynamic Simulator (FDS5) code, in which both solid-phase and gas-phase reactions are calculated. Two radiant heat flux, which are 16 and 25 kW/m² were studied, and an external air flow was varied from 3 to 40 cm/s. The simulation results showed that transient gas reaction flashed before a continuous flame was attached to the sample surface for gas flow velocities lower than a critical value. As the flow velocity is reduced, the flashing time, which is defined as the time when any flame is seen above the sample surface, decreases, while the duration of flashing increases. The solid surface temperature and mass flow rate increase rapidly during flashing. The ignition time, which is defined as the time when a continuous flame is attached to the fuel surface, decreases, reaches a minimum, and then increases until ignition cannot occur. Mechanisms were considered to explain the ‘‘V-shaped” dependence of ignition time on flow-velocity, and two regimes were identified each having a different controlling mechanism: the mass transport regime where the ignition delay is controlled by the mixing of oxygen and pyrolyzate; and the heat transfer regime where the ignition delay is controlled by changes in convection heat losses and critical mass flux for ignition. With the decrease of the airflow velocity, the critical mass flux shows a trend of decreasing and then increasing, which is dominated by the mixing of the pyrolyzate and the oxidizer, while the critical temperature monotonically decreases, which is dominated by a reduction of the net heat flux at the fuel surface. The results provide further insight into the ignition behavior of solid fuel under low-velocity flow environment, and guidance about fire safety in microgravity environments.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"36 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139061330","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 and Development of Cell Culture Devices Aboard the Chinese Space Station","authors":"Fangwu Liu,&nbsp;Shali Wu,&nbsp;Weibo Zheng,&nbsp;Yongchun Yuan,&nbsp;Qing Tian,&nbsp;Ping Fan,&nbsp;Mengrui Wu,&nbsp;Tao Zhang,&nbsp;Luyang Yu,&nbsp;Jinfu Wang","doi":"10.1007/s12217-023-10081-w","DOIUrl":"10.1007/s12217-023-10081-w","url":null,"abstract":"<div><p>Unprecedented experimental conditions were provided for research in space biology following the completion of the Chinese Space Station. The next decade is predicted to witness considerable developments in this subject. Space cell culture is a crucial experimental technique in space biology. The Cell Tissue Culture Experiment Module (CTCEM) aboard the space station's Biotechnology Experiment Rack is customized equipment designed for the microgravity environment in space. It provides suitable culture conditions for cell growth, including temperature and CO₂ concentration control, automatic liquid exchange, and automated observation via visible light microscopy, fluorescence microscopy, and laser confocal microscopy. The Tianzhou-5 Launch Cell Life Support Module (LCLSM) was developed to meet the requirements for transporting samples for space station cell experiments. This device can provide the required temperature, CO₂ concentration, and nutrient solution replacement for cell experiment sample transportation. It also stores cells during ground transportation, launches, and in-orbit flights to ensure that they arrive at a space station with good physiological conditions. This article describes space cell bioreactors, the detailed functions and usage methods of CTCEM and LCLSM, and discusses the entire process of transporting cells to the space station and conducting space cell culture experiments through the TZ5 mission.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"36 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138823504","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":"Expansion and Experimental Evaluation of Scaling Relations for the Prediction of Wheel Performance in Reduced Gravity","authors":"Adriana Daca,&nbsp;Dominique Tremblay,&nbsp;Krzysztof Skonieczny","doi":"10.1007/s12217-023-10087-4","DOIUrl":"10.1007/s12217-023-10087-4","url":null,"abstract":"<div><p>Traversing granular regolith, especially in reduced gravity environments, remains a potential challenge for wheeled rovers. Mitigating hazards for planetary exploration rovers requires testing in representative environments, but direct Earth-based testing fails to account for the effect of reduced gravity on the soil itself. Granular scaling laws (GSL) have been proposed in the literature to predict performance of a larger wheel based on tests with a smaller wheel, or to predict performance in one gravity level based on tests in another gravity level. However, this is the first work to experimentally validate GSL in reduced gravity. Here, an expanded version of existing GSL was evaluated experimentally by measuring performance of a single wheel driving through cohesionless lunar soil simulant GRC-1 aboard parabolic flights that reproduce the effects of lunar gravity, and comparing those results to scaled tests performed on the ground. This scaled-wheel testing achieved less than 10% prediction error on three measured output metrics: drawbar pull (i.e. net traction), sinkage, and power draw. Predictions also erred on the conservative side. Subsurface soil imaging revealed similar soil behavior between scaled tests. GSL thus offers an accurate and conservative method for predicting wheel performance in reduced gravity based on 1-g experiments, at least in cohesionless soil.</p></div>","PeriodicalId":707,"journal":{"name":"Microgravity Science and Technology","volume":"35 6","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138436217","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":"Gravity Unloading Method of Membrane Phased-array Antennas Using Electrostatic Adsorption","authors":"Wang Zhong,&nbsp;Jichuan Xiong,&nbsp;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}