Aerodynamic Torque of a Butterfly Valve—Influence of an Elbow on the Time-Mean and Instantaneous Aerodynamic Torque

2000 ◽  
Vol 122 (2) ◽  
pp. 337-344 ◽  
Author(s):  
F. Danbon ◽  
C. Solliec
Keyword(s):  
Indirect Method ◽  
Low Cost ◽  
Indirect Measurement ◽  
Butterfly Valve ◽  
Hot Wire ◽  
Straight Pipe ◽  
Fluid Forces ◽  
Large Size ◽  
Shaft Torque ◽  
Aerodynamic Torque

Many technological devices use butterfly valves to control the flow of the process or as safety unit. The principal advantages of this type of valve are their simplicity, their low cost, their speed of closing and the weak pressure drop which they produce when they are completely open. For installations of large size, the actuator of the valve can be very expensive; thus it is essential to know well the fluid forces and the resulting torque exerted on the valve. Consequently, the variation of the shaft torque of the butterfly valves according to the opening is of great interest to calculate the power of the actuator. Initially the flow around the valve is characterized by means of hot wire anemometry. It is noted that the disturbances induced by the elbow and/or the valve are felt until a distance from approximately 8 times the pipe diameter. A method of direct measurement by torquemeter and an indirect method by integration of the pressure forces on the faces of the valve give access to the time-mean and instantaneous torque on the valve shaft. Comparisons between the direct and indirect measurement of the torque are made before engaging the analysis of the results. Close to the full opening, the torque presents fluctuations harmful to suitable lifespan of the valve. Compared to the straight pipe case, the temporal and spectral analyses of the instantaneous torque prove that the elbow induces important fluctuations when the valve is completely open. Several tests carried out according to the valve/elbow spacing show that these effects disappear beyond a distance from 8 to 10 times the diameter of the pipe. [S0098-2202(00)02902-3]

An Indirect Method for the Measurement of Micro-Milling Forces

2019 ◽  
Author(s):  
Xiaohong Lu ◽  
Furui Wang ◽  
Kun Yang ◽  
Yixuan Feng ◽  
Steven Y. Liang
Keyword(s):  
Measurement System ◽  
Indirect Method ◽  
Low Cost ◽  
Indirect Measurement ◽  
Transmission System ◽  
Micro Milling ◽  
Force Sensors ◽  
Milling Machine ◽  
Milling Force ◽  
Milling Forces

Abstract Nowadays, the measurement of micro-milling forces is mainly achieved by a force transducer. However, the frequency of force signal is high, due to the spindle super-speed, which leads to failure of the micro-milling forces measurement by using common force sensors. Additionally, micro force sensors with high-resolution and high sampling frequency are preferred, but they are often expensive. To determine the average micro-milling force with low cost and high precision, we propose an indirect method, by determining the power of the main transmission system of a micro-milling machine. First, the measurement system for the micro-milling machine tool power was introduced, and various sensors were used to measure the current and voltage respectively. Then, a high-frequency sampling system based on the Labview was developed to process the current and voltage signals, and to obtain the power data of the main transmission system. Through this process, the indirect measurement of micro-milling forces was achieved. Finally, we validated the effectiveness of the developed on-line measurement system and the proposed indirect measurement method for average micro-milling force by using experiments. The proposed method is practical and low-cost, and it can lay the foundation for further research on cutting energy consumption.

Constructive Optimisation of the Propeller Type Mixing Devices Using the Virtual and Rapid Prototyping

2017 ◽  
Vol 68 (3) ◽  
pp. 453-458 ◽  
Author(s):  
Daniel Besnea ◽  
Alina Spanu ◽  
Iuliana Marlena Prodea ◽  
Gheorghita Tomescu ◽  
Iolanda Constanta Panait
Keyword(s):  
Rapid Prototyping ◽  
Low Cost ◽  
Scale Up ◽  
Three Dimensional ◽  
Rapid Identification ◽  
Multidisciplinary Optimization ◽  
External Diameter ◽  
Process Industries ◽  
Parametric Cad ◽  
Shaft Torque

The paper points out the advantages of rapid prototyping for improving the performances/constructive optimization of mixing devices used in process industries, here exemplified to propeller types ones. The multidisciplinary optimization of the propeller profile affords its design using parametric CAD methods. Starting from the mathematical curve equations proposed for the blade profile, it was determined its three-dimensional virtual model. The challenge has been focused on the variation of propeller pitch and external diameter. Three dimensional ranges were manufactured using the additive manufacturing process with Marker Boot 3D printer. The mixing performances were tested on the mixing equipment measuring the minimum rotational speed and the correspondent shaft torque for complete suspension achieved for each of the three models. The virtual and rapid prototyping method is newly proposed by the authors to obtain the basic data for scale up of the mixing systems, in the case of flexible production (of low quantities), in which both the nature and concentration of the constituents in the final product varies often. It is an efficient and low cost method for the rapid identification of the optimal mixing device configuration, which contributes to the costs reduction and to the growing of the output.

Low-cost Indirect Measurement Methods for Self-x Integrated Sensory Electronics for Industry 4.0

2020 ◽  
Vol 87 (s1) ◽  
pp. s79-s84
Author(s):  
Qummar Zaman ◽  
Senan Alraho ◽  
Andreas König
Keyword(s):  
Industry 4.0 ◽  
Degrees Of Freedom ◽  
Performance Metrics ◽  
Low Cost ◽  
Indirect Measurement ◽  
Measurement Methods ◽  
Instrumentation Amplifier ◽  
Performance Parameters ◽  
Current Feedback ◽  
Indirect Measurements

AbstractThe conventional method for testing the performance of reconfigurable sensory electronics of industry 4.0 relies on the direct measurement methods. This approach gives higher accuracy but at the price of extremely high testing cost and does not utilize the new degrees of freedom for measurement methods enabled by industry 4.0. In order to reduce the test cost and use available resources more efficiently, a primary approach, called indirect measurements or alternative testing has been proposed using a non-intrusive sensor. Its basic principle consists in using the indirect measurements, in order to estimate the sensory electronics performance parameters without measuring directly. The non-intrusive property of the proposed method offers better performance of the sensing electronics and virtually applicable to any sensing electronics. Efficiency is evaluated in terms of model accuracy by using six different classical metrics. It uses an indirect current-feedback instrumentation amplifier (InAmp) as a test vehicle to evaluate the performance parameters of the circuit. The device is implemented using CMOS 0.35 μm technology. The achieved maximum value of average expected error metrics is 0.24, and the lowest value of correlation performance metrics is 0.91, which represent an excellent efficiency of InAmp performance predictor.

Sensible use of observational clinical data

2011 ◽  
Vol 22 (1) ◽  
pp. 7-13 ◽  
Author(s):  
J Marc Overhage ◽  
Lauren M Overhage
Keyword(s):  
Health Care ◽  
Clinical Trials ◽  
Medical Research ◽  
Observational Data ◽  
Clinical Data ◽  
Low Cost ◽  
Clinical Care ◽  
Data Sets ◽  
Large Size ◽  
Health Care Operations

Observational data sets offer many potential advantages for medical research including their low cost, large size and generalisability. Because they are collected for clinical care and health care operations purposes, observational data sets have some limitations that must be considered in order to perform useful analyses. Sensible use of observational data sets can yield valuable insights, particularly when clinical trials are impractical.

scholarly journals Swedish Weight Sounding: A prospective portable soil investigation tools for liquefaction assessment of residential houses in Indonesia

2020 ◽  
Vol 156 ◽  
pp. 02010
Author(s):  
Yusa Muhamad ◽  
Bowman Elisabeth T. ◽  
Nugroho S.A
Keyword(s):  
Indirect Method ◽  
Direct Method ◽  
Low Cost ◽  
Fine Sand ◽  
Good Prospect ◽  
Torque Measurement ◽  
Liquefaction Potential ◽  
Potential Index ◽  
National Disaster ◽  
Liquefaction Assessment

National Disaster Management Agency (BNPB) statistics show that the majority of earthquake affected buildings are residential houses, whereas in practice, soil investigation is rarely conducted for residential houses in Indonesia. This study is preliminary work on the prospective of Swedish Weight Sounding (SWST) for liquefaction assessment for residential houses. Material used is poorly graded sand. The number of half turns from SWST (NSW) per meter for very loose and loose clean fine sand ranges from 4 to 168 (equivalent to SPT 0-30). Liquefaction potential was assessed using an indirect method by converting NSW into equivalent NSPT and direct method. In general, the factor of safety obtained from the direct method is more conservative (thus giving lower liquefaction potential index) than the indirect method. Torque measured for material in this study ranged from 6-54 Nm, equivalent to a specific energy range from 7-70 N/mm2. Liquefaction assessment using SWST data with torque measurement also indicated the soil is liquefiable. SWST also may be able to detect sand ageing. In summary SWS has a good prospect as a highly portable and low cost investigation tool for liquefaction assessment of residential houses in Indonesia.

A New Flexible Track Automatic Drilling System

2013 ◽  
Vol 433-435 ◽  
pp. 2178-2183 ◽  
Author(s):  
Yun Bo Bi ◽  
Yi Hang Jiang ◽  
Yong Chao Li ◽  
Wei Wang ◽  
Mian Gao ◽  
...  
Keyword(s):  
High Efficiency ◽  
Low Cost ◽  
System Structure ◽  
Aircraft Assembly ◽  
Large Size ◽  
Flexible Track ◽  
Transformation Algorithm ◽  
Drilling System ◽  
High Computational Efficiency

The Flexible track automatic drilling equipment is widely used in aircraft assembly because of the low cost, high efficiency and high quality of holes. This paper constructs a new flexible track drilling system for large-size aircraft assembly. The system structure is introduced, and the transformation algorithm between product/device coordinate system and axes position parameters is proposed. The experimental results show that the transformation algorithm has the merits of high computational efficiency and high stability, and can meet the requirement of precision drilling.

scholarly journals Effectiveness of selective area growth using van der Waals h-BN layer for crack-free transfer of large-size III-N devices onto arbitrary substrates

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Soufiane Karrakchou ◽  
Suresh Sundaram ◽  
Taha Ayari ◽  
Adama Mballo ◽  
Phuong Vuong ◽  
...  
Keyword(s):  
Low Cost ◽  
Van Der Waals ◽  
Thermal Dissipation ◽  
Silicon Substrates ◽  
Device Performance ◽  
Selective Area Growth ◽  
Material Quality ◽  
Large Size ◽  
Selective Area ◽  
Area Growth

AbstractSelective Area van der Waals Epitaxy (SAVWE) of III-Nitride device has been proposed recently by our group as an enabling solution for h-BN-based device transfer. By using a patterned dielectric mask with openings slightly larger than device sizes, pick-and-place of discrete LEDs onto flexible substrates was achieved. A more detailed study is needed to understand the effect of this selective area growth on material quality, device performance and device transfer. Here we present a study performed on two types of LEDs (those grown on h-BN on patterned and unpatterned sapphire) from the epitaxial growth to device performance and thermal dissipation measurements before and after transfer. Millimeter-size LEDs were transferred to aluminum tape and to silicon substrates by van der Waals liquid capillary bonding. It is shown that patterned samples lead to a better material quality as well as improved electrical and optical device performances. In addition, patterned structures allowed for a much better transfer yield to silicon substrates than unpatterned structures. We demonstrate that SAVWE, combined with either transfer processes to soft or rigid substrates, offers an efficient, robust and low-cost heterogenous integration capability of large-size devices to silicon for photonic and electronic applications.

scholarly journals Single-Seed Casting Large-Size Monocrystalline Silicon for High-Efficiency and Low-Cost Solar Cells

Engineering ◽  
2015 ◽  
Vol 1 (3) ◽  
pp. 378-383 ◽  
Author(s):  
Bing Gao ◽  
Satoshi Nakano ◽  
Hirofumi Harada ◽  
Yoshiji Miyamura ◽  
Takashi Sekiguchi ◽  
...  
Keyword(s):  
Solar Cells ◽  
High Efficiency ◽  
Low Cost ◽  
Monocrystalline Silicon ◽  
Single Seed ◽  
Large Size

Aerodynamic Torque Acting on a Butterfly Valve. Comparison and Choice of a Torque Coefficient

1999 ◽  
Vol 121 (4) ◽  
pp. 914-917 ◽  
Author(s):  
C. Solliec ◽  
F. Danbon
Keyword(s):  
Pressure Drop ◽  
Static Pressure ◽  
Fluid Dynamic ◽  
Dynamic Pressure ◽  
Low Cost ◽  
Normalization Method ◽  
Pressure Drops ◽  
Torque Coefficient ◽  
Aerodynamic Torque ◽  
Valve Pressure

Most technological devices use butterfly valves to check the flow rate and speed, through piping. Their main advantages are their low cost, their mechanical suitability for fast operation, and their small pressure drops when they are fully open. The fluid dynamic torque about the axis of large valves has to be considered as the actuator could be overstrained. This torque is generally defined using a nondimensional coefficient KT, in which the static pressure drop created by the valve is used for normalization. When the valve is closed downstream of an elbow, the valve pressure drop is not well defined. Thus, the classic normalization method gives many ambiguities. To avoid the use of the pressure drop, we define another torque coefficient CT in which the dynamic pressure of the flow is the normalization factor instead of the pressure drop. Advantages and drawbacks of each normalization method are described in the following.

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