Experiment Investigation on Fluid Storage Characteristic and Transportation Performance of Propellant Refillable Reservoir in Microgravity Environment

2013 ◽  
Vol 390 ◽  
pp. 91-95 ◽  
Author(s):  
Bao Tang Zhuang ◽  
Yong Li ◽  
Ha Lin Pan ◽  
Qi Hu
Keyword(s):  
Surface Tension ◽  
Rational Design ◽  
Storage Capacity ◽  
Fluid Management ◽  
Test System ◽  
Space Environment ◽  
Lateral Acceleration ◽  
Microgravity Environment ◽  
Test Results ◽  
Liquid Storage

Satellites store and manage propellant by surface tension. A surface tension propellant management device (PMD) consists of a propellant refillable reservoir (PRR) for propellant storage and propellant acquisition vanes (PAVs) for propellant transportation. PRR is a key part of vane type surface tension tank (STT), and its storage performance determines the fluid management of vane type STT. In the present paper, a model test system was established and microgravity drop tower tests conducted based on experimental study of fluid storage and transportation behavior of PRR. Laws of fluid storage and transportation of PRR in microgravity environment were obtained. The test results show that two types of PRR both have good liquid storage capacity, and the double cone PRR exhibits good liquid storage capacity in lateral acceleration. A rational design of PRR can effectively store liquid and control liquid transportation velocity. The test results offer a guideline for optimization of new-style vane type PMD, and also provide a new method for fluid control in space environment.

Research on Fluid Transmission Performance of Propellant Acquisition Vane Under Microgravity Environment

2015 ◽  
Author(s):  
Qi Hu ◽  
Xianwu Luo
Keyword(s):  
Fluid Management ◽  
Separation Distance ◽  
Test System ◽  
Space Environment ◽  
Lateral Acceleration ◽  
Microgravity Environment ◽  
Optimized Design ◽  
Transmission Performance ◽  
Transmission Velocity ◽  
Section Form

Propellant acquisition vane (PAV) is a key part of vane type surface tension tank (STT) and is mostly used to transmit fluid under microgravity environment, its transmission performance will determine fluid management of STT. In present paper, a ribbon type PAV with hems on both sides is conceptually designed, and its transmission performance has been analyzed based on four configuration parameters of its section form, which are flat part breadth, hems’ height, hems’ angle and separation distance between PAV and inner wall of STT. The laws of the effects of four configuration parameters on PAV’s transmission performance have been obtained and a set of most optimized configuration parameters has been given. Then transmission performance of the PAV whose configuration parameters of section form are the set of optimized parameters has been studied in-depth. Our results revealed that the optimized PAV is able to meet orbital demand of gas-free propellant completely during the end of STT’s life under harsh microgravity environment. On the basis of analyzed laws, microgravity environment has been conducted by the hundred meters drop tower tests, so the model test system with PAV is established and the campaigns have as objective to test the PAV’s fluid transmission performance under axial and lateral acceleration conditions. All these analyses and tests have been successfully conducted to demonstrate fluid transmission performance of such a PAV. According to present research, PAV with different section forms influences fluid transmission performance of STT remarkably. Thus, it is an effective way to control liquid transmission velocity by reasonably design of section form of PAV. Present research can not only provide a guideline for optimized design of new-style vane type fluid management assembly, but also present a new way for liquid control in space environment.

Exploration of Unsteady Spray Cooling for High Power Electronics at Microgravity Using NASA Glenn’s Drop Tower

2005 ◽  
Author(s):  
Eric L. Golliher ◽  
Chad P. Zivich ◽  
S. C. Yao
Keyword(s):  
High Power ◽  
High Speed ◽  
Fluid Management ◽  
Thermal Response ◽  
Spray Cooling ◽  
High Heat ◽  
Drop Tower ◽  
Space Environment ◽  
Microgravity Environment ◽  
High Heat Flux

At present, there is little understanding of the application of spray cooling to electronics in the microgravity environment. Typically in closed cycle terrestrial spray cooling systems, since not all of the liquid impinging on a hot substrate is evaporated, some residual liquid is separated from its vapor component by gravity and returned to the pump. This technique of phase separation is not available to spacecraft designers. Methods to predict spray cooling performance for ground systems do exist, but they are absent for the space environment. Particularly for NASA spacecraft, there is a need to design spacecraft that use high power laser systems and other systems that use evaporative spray cooling in microgravity. Such knowledge is very important for the performance and life of the device. Reliable analytical methods of predicting thermal response of a spray cooled substrate when considering a transient heat load, such as that found during start up and shut down of a space-based laser or other high heat flux electronics, do not exist. Our goal was to use NASA Glenn’s 2.2 second drop tower to investigate unsteady heat transfer at low Bond numbers and residual fluid behavior in spray cooling. The work contrasts other experiments aboard the NASA Glenn KC-135 low gravity aircraft [1]. Our future plans are to continue the experimental work and include the use of the NASA Glenn 5 second drop tower. This paper will report on some preliminary results of an interesting experimental study performed at NASA Glenn in the summer of 2004. The high speed camera and specially-designed “S.L.O.B.” drop rig provided video and data to assess the fluid management problems that arise in a microgravity spray environment, for both heated and unheated cases. The data show unexpected residual fluid management issues, such as the development of multiple spherical liquid globs, with apparent ordered and repeatable geometry, at the point of impact. The results of these experiments provide direction for further investigation in the future.

DIP quality influenced by process water quality

TAPPI Journal ◽  
2014 ◽  
Vol 13 (9) ◽  
pp. 51-60
Author(s):  
DENNIS VOSS ◽  
HANS-JOACHIM PUTZ ◽  
SAMUEL SCHABEL
Keyword(s):  
Water Quality ◽  
Surface Tension ◽  
Ph Value ◽  
Water Hardness ◽  
Process Water ◽  
Test Results ◽  
Negative Effects ◽  
Water Parameters ◽  
Effects Of Ph ◽  
Contamination Levels

The need for deinking mills to reduce their fresh water consumption has resulted in higher loads of various contaminants in the process water. Lower recovered paper quality also leads to higher contamination levels in the mills. This higher load has an influence on achievable target brightness. The objective of the work was to determine and explain the main reasons for relatively poor deinked pulp quality or poor deinking potential based on the influence of recovered paper composition and process water quality. The process water parameters significantly affect the deinking potential of recovered paper. The test results showed the negative effects of increased water hardness. For standard recovered paper mixtures, flotation selectivity is higher with increasing flotation pH-value. Good results were realized for standard recovered paper with low hardness, low surface tension, and high pH-value. The results for recovered paper containing flexo newsprint could be slightly improved with low hardness, low surface tension, and low pH-value. The results of the test program using design of experiments showed interacting effects of pH-value and surface tension on luminosity and flotation selectivity.

Framework and performance analysis of college English testing system based on data mining technology

2021 ◽  
pp. 1-11
Author(s):  
Liu Narengerile ◽  
Li Di ◽  
Keyword(s):  
Data Mining ◽  
Test System ◽  
Test Time ◽  
Testing System ◽  
Test Results ◽  
System Software ◽  
Examination System ◽  
Mining Technology ◽  
College English ◽  
And Performance

At present, the college English testing system has become an indispensable system in many universities. However, the English test system is not highly humanized due to problems such as unreasonable framework structure. This paper combines data mining technology to build a college English test framework. The college English test system software based on data mining mainly realizes the computer program to automatically generate test papers, set the test time to automatically judge the test takers’ test results, and give out results on the spot. The test takers log in to complete the test through the test system software. The examination system software solves the functions of printing test papers, arranging invigilation classrooms, invigilating teachers, invigilating process, collecting test papers, scoring and analyzing test papers in traditional examinations. Finally, this paper analyzes the performance of this paper through experimental research. The research results show that the system constructed in this paper has certain practical effects.

Rational design of flower-like Co–Zn LDH@Co(H2PO4)2 heterojunctions as advanced electrode materials for supercapacitors

2021 ◽  
Vol 50 (13) ◽  
pp. 4643-4650
Author(s):  
Miao He ◽  
Yi He ◽  
Xinyi Zhou ◽  
Qiang Hu ◽  
Shixiang Ding ◽  
...  
Keyword(s):  
Energy Storage ◽  
Specific Capacitance ◽  
Rational Design ◽  
Electrode Materials ◽  
Storage Capacity ◽  
Energy Storage Capacity

The device exhibits 95.3% retention in specific capacitance after 5000 cycles and possesses superior energy-storage capacity.

The Research of IC Test Based on LTX-77 Test System

2014 ◽  
Vol 496-500 ◽  
pp. 1176-1179
Author(s):  
Li Tan ◽  
Yu Fang
Keyword(s):  
Test Object ◽  
Test System ◽  
Test Method ◽  
Test Results ◽  
Analog Ic ◽  
Test Platform ◽  
Logic Functions ◽  
Actual Test ◽  
Ic Test

LTX-77 test system is a large IC test system that is used for various kinds of analog IC, digital IC and analog digital mixed IC. It can be used to test DC parameters, AC parameters and logic functions. In the paper, the IC test platform is LTX-77 test system. IC ADC0804 was tested as the test object. The test method of IC is described in the view of actual test. The test results show that the test system is convenient and accurate, which has important practical value for IC manufacturers and users.

The Improved Friction Properties of Bonded MoS2 Films by MAO Treating of Al Substrate

2013 ◽  
Vol 275-277 ◽  
pp. 1911-1914 ◽  
Author(s):  
Han Jun Hu ◽  
Hui Zhou ◽  
Yu Gang Zheng ◽  
Kai Feng Zhang ◽  
Zhi Hua Wan
Keyword(s):  
Tribological Properties ◽  
Solid Lubricants ◽  
Ceramic Coatings ◽  
Test System ◽  
Test Method ◽  
Test Results ◽  
Specimen Test ◽  
Micro Arc Oxidation ◽  
A New Technique ◽  
Porous Microstructures

The bonded MoS2 films are widely used as solid lubricants in aerospace mechanisms due to their excellent tribological properties. Traditionally, the MoS2 was directly bonded on the Al substrate that was only treated by the technique named of sandblast. For improving the tribological properties of MoS2 films, micro arc oxidation (MAO) instead of sandblast was introduced as a new technique for treating of Al substrate. In this article, the tribological properties of MoS2 films which were bonded on different surface of Al substrate as mentioned above were discussed, respectively. It was concluded from the test results that the MoS2 films bonded on substrate treated by MAO have better tribological properties than those samples treated by sandblast. The endurance life against abrasion of the former is as high as twenty times of the latter by the stand test method of ball on disk using the UMT Multi-Specimen Test System. This test results could be illustrated by the following reasons. The first is the porous microstructures of MAO ceramic coatings on the Al substrate. The coatings have numerous pits to be good at increasing the binding force with the MoS2 films, and the pits can also provide a MoS2 lubricants reservoir during processes of friction. Both of them improved the MoS2 film’s ability of wear-protective. The second is that hardness of the coating is higher than the Al, and this ensures well wearing resistance, especially in practical application to big load-supporting moving parts, such as bearing, gear, etc…

scholarly journals Estimating the groundwater storage for future irrigation schemes

2021 ◽  
Author(s):  
Shaibu Abdul-Ganiyu ◽  
Kpiebaya Prosper
Keyword(s):  
Storage Capacity ◽  
Pumping Test ◽  
Groundwater Depth ◽  
Northern Ghana ◽  
Test Results ◽  
Groundwater Storage ◽  
Groundwater Occurrence ◽  
Static Water ◽  
Agricultural Use ◽  
Electrical Data

Abstract Presented in this paper is a feasibility study of groundwater for agricultural use (irrigation) in Northern Ghana. The study was conducted using Geo-electrical data, Boreholes drill logs, results of water quality, and results of the pumping test. The geo-electrical results were to unearth the lithology of the study area; it was found to be underlain with varying geology of both Precambrian and Paleozoic sedimentary formation. These formations consist of phyllite, schist, granite, meta-sediments, and meta-volcanics making up the Precambrian and sandstone, shale, siltstone, mudstones, granitiods also, of the Paleozoic sedimentary. Areas of low resistivity were targeted for drilling per the geophysical results of the profile, values between 24 and 100 ohm.m were zones of probable groundwater occurrence in the study. The groundwater storage capacity and the extractable storage capacity were estimated to be approximately 710,000 km3 and 290,000 km3. The pumping test results acquired from 81 boreholes from the study were used to analyze the sustainability and otherwise. However, groundwater depth was studied using the Static water level (SWL), areas of SWL around 22 m and 25 m are likely to have a shallow depth whereas areas of 17 m would have deeper groundwater depth.

The effect of ink formulation on colorimetric properties of inkjet printing considering the impact of substrates

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Darya Ewaznezhad Fard ◽  
Saeideh Gorji Kandi ◽  
Marziyeh Khatibzadeh
Keyword(s):  
Surface Tension ◽  
Physical Properties ◽  
Inkjet Printing ◽  
Methyl Cellulose ◽  
Test Results ◽  
Viscosity Modifier ◽  
Content Type ◽  
Polymeric Compounds ◽  
The Impact ◽  
Ink Formulation

Purpose The purpose of this study is to investigate the changes in the performance of ink formulations caused by the addition of compounds that improve the ink’s physical properties to achieve an optimum formulation for inkjet printing, because of the importance and simplicity of this method. Design/methodology/approach Ink samples were formulated using Acid Red 14 as ink colorant, different percentages of polymeric compounds including polyvinyl alcohol (PVA), polyvinylpyrrolidone and Carboxy methyl cellulose (CMC) as viscosity modifier compounds and surfactant as the surface tension enhancer. Formulated samples were adjusted in terms of fluid physical properties e.g. viscosity, density and surface tension, and the effect of used compounds on the improvement of both physical and colorimetric properties such as viscosity, surface tension, colorimetric coordinates and lightfastness has been evaluated to achieve the optimum printing inks to be printed on three different substrates. Findings The experimental observations showed that CMC was the most compatible compound as the viscosity modifier as its viscosity value was in the printable range of 2–22 cP. Moreover, a flow-curve test was applied to the ink samples and their Newtonian behavior was approved. Based on the spectrophotometric test results of printed samples, the samples containing PVA provided acceptable lightfastness in comparison to other ink samples on every used substrate. Originality/value An optimum relation between colorimetric coordinates of the printed samples and ink formulation could be considered and achieved.

PVAT - a Posture Video Analysis Tool

1993 ◽  
Vol 37 (15) ◽  
pp. 1045-1045
Author(s):  
Darlene Merced-Moore ◽  
Susan C. Adam
Keyword(s):  
Video Analysis ◽  
Human Performance ◽  
Body Movement ◽  
Body Part ◽  
Space Environment ◽  
Microgravity Environment ◽  
Analysis Tool ◽  
Video Footage ◽  
Input Parameters ◽  
Data Collection Technique

The Posture Video Analysis Tool (PVAT) has been developed to meet the special needs of ergonomist and human factors analyst at NASA Johnson Space Center. Often times these specialist must attempt to evaluate microgravity working posture from video footage not specifically recorded for the purposes of quantitative analysis. The purpose for developing PVAT was to provide a structured methodology in which these specialists could optimize the data collection technique. The PVAT is designed such that microgravity postures can be documented while systematically observing footage of astronauts working in a space environment. PVAT is an interactive Macintosh menu and button driven SupercardTM prototype. Users are provided with a set of input parameters related to the microgravity environment and human performance issues. The primary inputs are: subject code, body orientation, targeted body part, camera view (given subject location), body movement, and rating level. A secondary set of inputs is available for users wishing to document extraneous behaviors or activities such as bending, reaching, interruptions, etc. These secondary behaviors may be documented as part of the primary inputs or independently. Each entry is time stamped and stored automatically. Provisions are made that allow users to pause, tag incorrect selections, enter an “unsure” response and user comments. Data output is saved as a “text file” using tab delimiters for easy importation into programs such as Micrsoft EXCELTM. Future PVAT modifications will include adding more input parameters, data reduction capabilities, control of the video deck from the application, and an animated postural glossary.

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