scholarly journals Methodology to Evaluate Dripper Sensitivity to Clogging due to Solid Particles: An Assessment

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Rogério Lavanholi ◽  
Fabricio C. Oliveira ◽  
Antonio P. de Camargo ◽  
José A. Frizzone ◽  
Bruno Molle ◽  
...  

Emitter clogging is a major problem in microirrigation systems, which may result from the isolated or combined effects of physical, chemical, and biological agents. Clogging caused by suspended solid particles is the most common plugging form of emitters. Water quality and emitter geometry are key aspects in clogging processes. Any suitable test procedure to assess the sensitivity of drippers to clogging should take into account the predominant factors that influence clogging and must reproduce the field conditions. This research set out to assess the performance and suitability of a laboratory clogging test procedure in order to validate a methodology and to provide scientific results that may support the standardization of a clogging test method. The evaluated methodology has been used by the IRSTEA laboratory since 1974 (Platform of Research and experiment on Science and Technology for Irrigation - PReSTI, formerly LERMI) and its contents are currently being discussed by the ISO TC23/SC18 committee. The aim is to define a standardized testing protocol to evaluate the sensitivity of emitters to clogging due to solid particles. Replications analyzing the clogging resistance of four models of emitting pipes were carried out in a laboratory. The clogging test procedure enabled an accurate assessment of the combinations of concentration and size of particles that caused clogging in each model of dripper. However, a significant variability in degree of clogging was identified when the results of replications for each model of dripper were compared. Several requirements, concerns, and improvements related to the clogging test protocol were discussed.

Author(s):  
Chiara F. Ferraris ◽  
Paul E. Stutzman ◽  
Max Peltz

The sulfate resistance of cements used in the construction industry is traditionally assessed by measuring the expansion of a prism of 280 mm (11inch) length and 25 mm (1 inch) square cross section immersed in a sodium sulfate solution for at least one year. The duration of the experiment limits this test from being used as a performance-based determination of innovative mixtures of cementitious materials. In response to the need for a more rapid test protocol, the National Institute of Standards and Technology (NIST) has developed a new test method that measures the expansion of smaller bars (10 mm x 10 mm x 60 mm) made with neat cement paste. With these bars, similar expansion is achieved in less than 3 months, reducing the test duration by a factor of at least 4. This accelerated test method provides more rapid results consistent with the traditional test procedure, allowing for a shorter decision time and the screening of more materials.


2003 ◽  
Vol 1832 (1) ◽  
pp. 191-200 ◽  
Author(s):  
Jonathan S. Gould ◽  
Yamini V. Nanagiri ◽  
Rajib B. Mallick ◽  
Joseph D. Petruccelli ◽  
William C. Crockford

The objectives of this research were to evaluate the rapid triaxial test method for use in quality control of hot-mix asphalt production and, if possible, determine test conditions for reliable results. The scope of this study consisted of testing different mixes at two different temperatures and frequencies and evaluating the results. The equipment was rugged and portable, and the hardware and software were easy to handle and did not require extensive technician training. The results from this study show that modulus and phase angle values obtained from testing are sensitive to key mixture components and properties. The coefficients of variation of results obtained from tests conducted at 60°C and 1 Hz are low. Tests with fine-graded mixes showed good correlation of dynamic stiffness parameters with rutting, and the stiffness parameters were found to be sensitive to the ratio of dust to effective binder. One significant advantage of using this test procedure as a regular quality control tool is that decisions can be made on the basis of performance-related parameters rather than on the basis of volumetric properties only. In view of its desirable qualities, this test method seems to be usable on a regular basis for quality control testing. However, before it is used, agencies must adopt a test protocol and establish target values and allowable variations.


Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 686
Author(s):  
Amr Aboulela ◽  
Matthieu Peyre Lavigne ◽  
Amaury Buvignier ◽  
Marlène Fourré ◽  
Maud Schiettekatte ◽  
...  

The biodeterioration of cementitious materials in sewer networks has become a major economic, ecological, and public health issue. Establishing a suitable standardized test is essential if sustainable construction materials are to be developed and qualified for sewerage environments. Since purely chemical tests are proven to not be representative of the actual deterioration phenomena in real sewer conditions, a biological test–named the Biogenic Acid Concrete (BAC) test–was developed at the University of Toulouse to reproduce the biological reactions involved in the process of concrete biodeterioration in sewers. The test consists in trickling a solution containing a safe reduced sulfur source onto the surface of cementitious substrates previously covered with a high diversity microbial consortium. In these conditions, a sulfur-oxidizing metabolism naturally develops in the biofilm and leads to the production of biogenic sulfuric acid on the surface of the material. The representativeness of the test in terms of deterioration mechanisms has been validated in previous studies. A wide range of cementitious materials have been exposed to the biodeterioration test during half a decade. On the basis of this large database and the expertise gained, the purpose of this paper is (i) to propose a simple and robust performance criterion for the test (standardized leached calcium as a function of sulfate produced by the biofilm), and (ii) to demonstrate the repeatability, reproducibility, and discriminability of the test method. In only a 3-month period, the test was able to highlight the differences in the performances of common cement-based materials (CEM I, CEM III, and CEM V) and special calcium aluminate cement (CAC) binders with different nature of aggregates (natural silica and synthetic calcium aluminate). The proposed performance indicator (relative standardized leached calcium) allowed the materials to be classified according to their resistance to biogenic acid attack in sewer conditions. The repeatability of the test was confirmed using three different specimens of the same material within the same experiment and the reproducibility of the results was demonstrated by standardizing the results using a reference material from 5 different test campaigns. Furthermore, developing post-testing processing and calculation methods constituted a first step toward a standardized test protocol.


2013 ◽  
Vol 5 (6) ◽  
pp. 655-658
Author(s):  
Egidijus Mykolaitis ◽  
Andrius Styra ◽  
Vladas Vekteris

Iron is one of the most common elements in ground water. Bythe HN 24:2003 iron concentration in water can‘t be higher than200 μg/l. Water treatment with an acoustic field is a very relevanttopic. Acoustic field is widely used in industrion, medicine,chemical industry and manufacturing. When water is affectedby ultrasound, physical-chemical processes begin. Ultrasoundvibrations lead to dispersion, degasation and coagulation. Ironparticles connect to each other when distance between them istwo times bigger then their own radius. R = 2R. And if thisprocess continues particles connect one by one. In this article teststand and methodics using ultrasonic piezoceramic are shown. Santrauka Geležis – dažniausiai požeminiuose vandenyse aptinkama priemaiša, kuri prastina geriamojo vandens savybes, todėl būtina bendrosios geležies koncentraciją sumažinti iki 0,2 mg/l. Vienas iš geležies šalinimo būdu yra paremtas ultragarso panaudojimu. Straipsnyje glaustai aptarti bendrosios geležies būviai vandenyje, jos šalinimo metodai ir pateikta eksperimentinė metodika. Eksperimentas atliktas naudojant skirtingų dažnių garso bangas nuo 8 kHz iki 20 kHz diapazone. Akustinio lauko daromai įtakai nustatyti, naudojant skirtingų dažnių garso bangas, buvo panaudoti trys skirtingi vandens debitai. Iš gautų rezultatų suformuluotos išvados.


2021 ◽  
Vol 3 (2) ◽  
pp. 36-42
Author(s):  
Theresia Evila Purwanti Sri Rahayu ◽  
Rosita Dwityaningsih ◽  
Murni Handayani ◽  
Khoeruddin Witriansyah ◽  
Ayu Pramita

Wastewater resulted from the batik dying process is known for its environmentally hazardous substances including hazardous natural and synthetic organic matter, suspended particles, and hazardous metal. But in the micro and medium scale batik textile business, wastewater treatment is mostly not carried because it does not give benefit for the owner. Economical wastewater treatment constructions can be an alternative for the business owner for their free operational cost. Batik wastewater treatment ought to be carried out to meet government standards but most importantly to decrease hazardous pollutant’s concentrations so it does not harm the environment. This society service project aims to provide alternatively economical wastewater treatment for batik business owners by applying simples and cheapest yet effective treatment methods to reduce pollutant concentrations in wastewater. Methods applied in this project including sedimentation, filtration, and landfill-bioremediation. The laboratorium analysis result shows that sedimentation and filtration are significantly reduced total suspended solid particles in wastewater from 2450 to 100 mg/L in line with wastewater decoloring from dark blue to clear yellow.


Author(s):  
P. Bhattacharya ◽  
S. Nara ◽  
P. Vijayan ◽  
T. Tang ◽  
W. Lai ◽  
...  

A nanofluid is a fluid containing suspended solid particles, with sizes of the order of nanometers. The nanofluids are better conductors of heat than the base fluid itself. Therefore it is of interest to measure the effective thermal conductivity of such a nanofluid. We use temperature oscillation technique to measure the thermal conductivity of the nanofluid. However, first we evaluate the temperature oscillation technique as a tool to measure thermal conductivity of water. Then we validate our experimental setup by measuring the thermal conductivity of the aluminum oxide-water nanofluid and comparing our results with previously published work. Finally, we do a systematic series of measurements of the thermal conductivities of aluminum oxide-water nanofluids at various temperatures and explain the reasons behind the dependence of the enhancement in thermal conductivity of the nanofluid on temperature.


1985 ◽  
Vol 22 (4) ◽  
pp. 592-599
Author(s):  
R. G. Horvath

A multiple loading testing method is suggested, which permits testing a single drilled pier foundation under three different conditions of load support. The pier may be tested under conditions of combined shaft and end-bearing resistance, end-bearing resistance only, and shaft resistance only. The advantages of this multiple loading test method include observation of the load-transfer and displacement behaviours of the pier under these three different support conditions and verification of the values obtained for the components of load support, i.e., shaft and end-bearing resistance, all from a single test pier.A special base load cell capable of performing a different function during each cycle of loading is required. A suitable load cell, consisting of a series of Freyssi flatjacks, and the method of operation are described.A multiple loading test procedure was used successfully as part of a field investigation program on full-scale pier sockets in weak shale. Data on the load-displacement behaviour of the pier tested using the multiple loading method are reported. Information concerning piers tested using conventional single loading methods are provided for comparison.The multiple loading test results were in good agreement with results obtained from conventional testing methods. Thus the multiple loading test method provides an economical means of obtaining a large amount of design information for drilled pier foundation systems, using a single test pier. Key words: field load test, multiple loading, drilled piers and caissons, shaft resistance, end-bearing resistance, combined shaft and end-bearing resistances, base load cell, shale.


2019 ◽  
Vol 4 (1) ◽  
pp. 41-55 ◽  
Author(s):  
Jan Hummel ◽  
Dietmar Göhlich ◽  
Roland Schmehl

Abstract. We have developed a tow test setup for the reproducible measurement of the dynamic properties of different types of tethered membrane wings. The test procedure is based on repeatable automated maneuvers with the entire kite system under realistic conditions. By measuring line forces and line angles, we determine the aerodynamic coefficients and lift-to-drag ratio as functions of the length ratio between power and steering lines. This nondimensional parameter characterizes the angle of attack of the wing and is varied automatically by the control unit on the towed test bench. During each towing run, several test cycles are executed such that mean values can be determined and errors can be minimized. We can conclude from this study that an objective measurement of specific dynamic properties of highly flexible membrane wings is feasible. The presented tow test method is suitable for quantitatively assessing and comparing different wing designs. The method represents an essential milestone for the development and characterization of tethered membrane wings as well as for the validation and improvement of simulation models. On the basis of this work, more complex maneuvers and a full degree of automation can be implemented in subsequent work. It can also be used for aerodynamic parameter identification.


Author(s):  
Jose´ C. Veiga ◽  
Carlos F. Cipolatti ◽  
Ana M. Furtado

This paper presents a Superheated Steam Test Rig and a Test Procedure for Compressed Non-Asbestos (CNA) Gaskets qualification. The Test Rig is a versatile assembly that can use different flange sizes and heating systems. It simulates a Superheated Steam Boiler with a water feed pump, pressurized water tank, pressure relief valve, condenser and the flange pair acting as the Steam generation unit. Heating can be provided by an oven or heating element bands. The Test Protocol enables the evaluation of the gasket performance in Superheated Steam in severe operational conditions like high pressure and temperature with thermal cycling. Different types of non-asbestos compressed gaskets were tested monitoring the leak rate and bolt load at each thermal cycle.


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