scholarly journals Sensor Based Leakage Detection in Vacuum Bagging

2021 ◽  
Author(s):  
Anja Haschenburger ◽  
Niklas Menke ◽  
Jan Stüve
Keyword(s):  
Flow Rate ◽  
Air Flow ◽  
Volumetric Flow Rate ◽  
Detection Methods ◽  
Industrial Processes ◽  
Special Focus ◽  
Leakage Detection ◽  
Flow Meters ◽  
New Approach

Abstract The majority of aircraft components are nowadays manufactured using autoclave processing. Essential for the quality of the component is the realization of an air tight vacuum bag on top of the component to be cured. Several ways of leakage detection methods are actually used in industrial processes. They will be dealt with in this paper. A special focus is put on a new approach using flow meters for monitoring the air flow during evacuation and curing. This approach has been successfully validated in different trials, which are presented and discussed. The main benefit of the method is that in case of a leakage, a defined limit is exceeded by the volumetric flow rate whose magnitude can be directly correlated to the leakage’s size and position. In addition the potential of this method for the localization of leakages has been investigated and is discussed.

scholarly journals Sensor-based leakage detection in vacuum bagging

2021 ◽  
Author(s):  
Anja Haschenburger ◽  
Niklas Menke ◽  
Jan Stüve
Keyword(s):  
Flow Rate ◽  
Air Flow ◽  
Volumetric Flow Rate ◽  
Detection Methods ◽  
Industrial Processes ◽  
Special Focus ◽  
Leakage Detection ◽  
Flow Meters ◽  
New Approach

AbstractA majority of aircraft components are nowadays manufactured using autoclave processing. Essential for the quality of the component is the realization of an airtight vacuum bag on top of the component to be cured. Several ways of leakage detection methods are actually used in industrial processes. They will be dealt with in this paper. A special focus is put on a new approach using flow meters for monitoring the air flow during evacuation and curing. This approach has been successfully validated in different trials, which are presented and discussed. The main benefit of the method is that in case of a leakage, a defined limit is exceeded by the volumetric flow rate whose magnitude can be directly correlated to the leakage’s size and position. In addition, the potential of this method for the localization of leakages has been investigated and is discussed.

scholarly journals The Air Flow Distribution in the Overpressure Sowing Apparatus

2020 ◽  
Vol 14 (1) ◽  
pp. 40-45
Author(s):  
A. Yu. Popov
Keyword(s):  
Flow Velocity ◽  
Flow Rate ◽  
Air Flow ◽  
Flow Distribution ◽  
Volumetric Flow Rate ◽  
Air Velocity ◽  
Air Flow Velocity ◽  
Flow Propagation

To improve the quality of the pneumatic sowing apparatus, it is necessary to study its aerodynamics. (Research purpose) Determination of air flow distribution in the upper part of the seed chamber of the sowing apparatus, taking into account the protrusions of the sowing disk, on which the quality of seeds dosing depends. (Materials and methods) The author chose a sowing apparatus operating at overpressure as an object of research. The author showed that the seed chamber constant sealing in it is provided by the protrusions of the sowing disk, which are made with cut edges on the side of the sowing disk metering element in two planes. The author applied computer simulation of the sowing apparatus. To conduct a numerical experiment, the initial and boundary conditions were determined, and the rotation of the seed disk was taken into account. The calculation of the model was carried out by changing the volumetric air flow in the range of 15-35 liters per second. (Results and discussion) The author constructed isolines of the air velocity distribution at various air flow rates. He determined the values of the air flow in the directions X, Y and Z in the sowing apparatus seed chamber. It was revealed that the largest and the smallest values of this indicator are achieved at 35 and 25 liters per second respectively. It was shown that at an air flow rate in the range of 15-25 liters per second, the distribution of the air flow in the upper part of the seed chamber would be optimal for transporting the seeds with a metering element. The air flow velocity components in Z direction vary in the range from 5.4 to 16.5 meters per second, and in the X and Y directions do not exceed 8 meters per second. (Conclusions) Based on simulation modeling, the author constructed and analyzed graphs of air flow velocity components changes in the three directions of air flow propagation. He determined the nature of the distribution of air flow in the excess seeds discharge area in the design of protrusions with cut corners. He proposed a rational range of air volumetric flow rate of 15-25 liters per second.

Improving Biogas Quality through Circulated Water Scrubbing Method

2015 ◽  
Vol 776 ◽  
pp. 443-448 ◽  
Author(s):  
Hendry Sakke Tira ◽  
Yesung Allo Padang ◽  
Mirmanto ◽  
Hendriono
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Sulfide ◽  
Flow Rate ◽  
Fossil Fuels ◽  
Volumetric Flow Rate ◽  
Calorific Value ◽  
Energy Resources ◽  
Dissolve Carbon Dioxide ◽  
Biogas Purification

The dependence of human being on fossil fuels has decreased significantly the conventional energy resources. To overcome this problem it is required alternative substitute fuels which are cheap and accessible which biogas is one of the fuels. Nevertheless, the use of biogas has not yet been maximized because of the low calorific value which is produced from the process without purification. The circulated water absorption method is one mean of effective biogas purification. Under this method it is expected to increase the level of methane (CH4) and to reduce both the level of carbon dioxide (CO2) and hydrogen sulfide (H2S). In order to obtain the aim, the research was carried out under variations of water and biogas volumetric flow rate. The results show that the highest quality of biogas produced was under the variation of water volumetric flow rate of 15 lt/min with biogas volumetric flow rate of 1 lt/min which increased the level of methane (CH4) from 59.36 % to 62.8 % and decreased the carbon dioxide (CO2) content from 33.53 % to 26.8 %, and hydrogen sulfide (H2S) from 208.33 to 86 ppm. Lower biogas and water volumetric rates allowed longer contact between biogas molecule and absorbent. This resulted in an opportunity for absorbent more active to dissolve carbon dioxide and hydrogen sulfide in biogas. These compounds then flowed outward of the scrubbing unit along with the absorbent. The research proved that the raw biogas purification by circulated water scrubbing method was an effective mean in enhancing the quality of biogas.

scholarly journals Development of a low-cost prototype

2021 ◽  
Vol 9 (8) ◽  
pp. 328-337
Author(s):  
Katiane Pereira da Silva ◽  
Enoque Coutinho dos Santos ◽  
Ramildo Felipe Silva Gonçalves ◽  
Antonio Thiago Madeira Beirão ◽  
Fábio Israel Martins Carvalho ◽  
...  
Keyword(s):  
Undergraduate Students ◽  
Flow Rate ◽  
Teaching And Learning ◽  
Low Cost ◽  
Volumetric Flow Rate ◽  
Experimental Models ◽  
Theory And Practice ◽  
Theoretical Concepts ◽  
Experimental Values

This study aims to develop a low-cost prototype to measure the mass and volumetric flow rate of fluids through the construction of a Pitot Tube. This meter must be able to measure the mass flow rate of air for different pressure values using only the water height level variation. For the development of the prototype, low-cost materials were used, in addition to some necessary tools. These experimental models are a didactic proposal for teaching and learning about the flow of fluids discipline, where it was verified that the experimental values found presented satisfactory results correlated with the theoretical concepts of an ideal fluid present in the literature. Thus, the Bernoulli and Torricelli equations were applied to assess the quality of the measurement method, to facilitate the learning of undergraduate students in the Production Engineering Course through conciliation between theory and practice in the Fluid Mechanics Laboratory discipline classes. Finally, the prototype experiment was exposed to other students at the institutional event called “I Integrar Produção” held by UFRA at the Parauapebas Campus.

scholarly journals Effect of Needle Size and Volumetric Flow Rate on Root Canal Irrigation: A Numerical Investigation

2019 ◽  
Author(s):  
Mohammad Ghalandari ◽  
Mona Malek ◽  
Hossein Alizadeh ◽  
Fatemeh Ghalandari ◽  
Amir Mosavi ◽  
...  
Keyword(s):  
Flow Rate ◽  
Root Canal ◽  
Fluid Dynamic ◽  
Volumetric Flow Rate ◽  
Needle Size ◽  
Canal Irrigation ◽  
Root Canal Irrigation ◽  
Root Canal Disinfection ◽  
Computation Fluid Dynamic

Among the different applicable irrigants for root canal disinfection, sodium hypochlorite 5.25% is one of the most attractive ones. The quality of root canal disinfection is dependent on some factors such as the employed approach, type of flow rate of irrigant and the size of needle. The majority of studies in the field of root canal disinfection are experimentally carried out. In the current article, Computation Fluid Dynamic (CFD) is used for modeling the antimicrobial liquid flow in the root canal and evaluate the effects of needle size and flow rate. Two needles, G28 and G30, are used for irrigation in three volumetric rates of flow including 0.10 mL⁄s , 0.20 mL⁄s and 0.30 mL⁄s. The results of numerical simulations revealed the improved quality of root canal disinfection by augmentation in the rate of flow and decrease in the inner diameter of the needle. According to the outcomes of the modeling, the highest average wall shear stress obtained in the case of using G28 needle and 30 mL⁄s flow rate, which was approximately 10.21 Pa.

scholarly journals Optimization of injected radiotracer volume for flow rate measurement in closed conduits

2020 ◽  
Vol 74 (5) ◽  
pp. 305-312
Author(s):  
Miroslav Pavlovic ◽  
Marijana Pantovic-Pavlovic ◽  
Pavel Bartl ◽  
Jasmina Stevanovic ◽  
Bojan Radak
Keyword(s):  
Flow Rate ◽  
Fluid Velocity ◽  
Plug Flow ◽  
Volumetric Flow Rate ◽  
Pilot Scale ◽  
Quality Performance ◽  
Flow Meters ◽  
Injection Volume ◽  
In Situ Calibration ◽  
Flow Quality

In chemical processes it is essential that the flow in the process is accurately defined. Fluid velocity measurements are important for fluid flow quality performance in flow systems. This study focuses on determination of the volumetric flow rate and its standard (relative) deviation for calibration of conventional flow meters by using a radiotracer approach. The measurements for flow meter calibration were performed at a pilot-scale flow rig using Technetium-99 m (99mTc) as a radiotracer in the form of pertechnetate ion (99mTcO4-). The measured data were analyzed, and precision of the experimental setup was investigated under two different approaches ? IAEA?s RTD software and sum approximation of raw data. For the first time, the variation of standard deviation of calculated flow rate with the injection volume and activity of the radiotracer was determined. Plug flow with axial dispersion was used to simulate the measured RTD curves and investigate the flow dynamics of the flowing water. The results of the study have shown the possibility of in situ calibration of flow meters with a relative error lower than 1 %. They also revealed a slight dependency of the precision of output results on the injection volume as well as similar results for manual and specialized RTD software data processing.

scholarly journals Considerations About the Required Volumetric Air Flow Rate Inside an Office Room with One Occupant – Case Study

2020 ◽  
Vol 10 (1) ◽  
pp. 31-38
Author(s):  
P. Kapalo ◽  
F. Domniţa ◽  
O. Pop ◽  
M. Adamski ◽  
O. Voznyak
Keyword(s):  
Flow Rate ◽  
Air Flow ◽  
Accurate Determination ◽  
Minimum Energy ◽  
Volumetric Flow Rate ◽  
Precise Determination ◽  
Air Flow Rate ◽  
Minimum Energy Consumption ◽  
Body Parameters

AbstractIn the construction process of modern buildings, the aim is to achieve maximum comfort within minimum energy consumption. One of the ways to achieve this requirement is the accurate determination of the volumetric flow rate of fresh air, necessary to ensure the required indoor air quality. This study begins with the experimental determination of carbon dioxide (CO2) concentration in an office room with one occupant performing three types of activities with different levels of physical intensities. Based on these measurements, a methodology for the precise determination of the volumetric air flow rate is presented. This method was compared with another one that takes into account body parameters and is considered in this study as the most accurate. The required outdoor air flow rate for the experimental room was also determined based on the present legislations of five different countries. Comparing all the studied methods and considering as refence the method based on body parameters, it was found that the accuracy of the values is influenced by the physical intensity of the activity and that most methods generally underestimate the amount of required fresh air.

The Effect of Temperature and Air Flow Rate on the Quality of Dried Rapeseed

1973 ◽  
Vol 16 (4) ◽  
pp. 0814-0816 ◽  
Author(s):  
K. E. McKnight ◽  
E. B. Moysey
Keyword(s):  
Flow Rate ◽  
Air Flow ◽  
Effect Of Temperature ◽  
Air Flow Rate

Security Concern and Countermeasures for Cheating in Visual Cryptography

2018 ◽  
Vol 6 (8) ◽  
pp. 277
Author(s):  
Ekta Y
Keyword(s):  
Communication System ◽  
Visual Cryptography ◽  
Detection Methods ◽  
Information Communication ◽  
New Approach ◽  
The World ◽  
Visual Cryptography Scheme ◽  
Prevention Methods ◽  
Security Concern

As IT sector is ruling the world now,confidentiality and security of information has become the most important inseparable aspect in information communication system. Keeping in view the same, a new approach called Visual Cryptography (VC) has been suggested by many researchers but there are some limitations with this scheme and cheating is one of the main problem among them. This paper intends to show the basis of cheating in VC in terms of cheating process, its detection methods and its prevention methods suggested by various researchers along with their merits and demerits. Finally, a good Cheating Immune Visual Cryptography Scheme (CIVCS) has been discussed which states the properties to be adopted by every Visual Cryptography scheme to make it immune to cheating attacks.

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