A theoretical relation for estimating the frequency response of diaphragm pore pressure transducers is derived by considering the interaction between the diaphragm, porous cap, air, and pore fluid inside the transducer. Using this relation, the frequency response of a pore pressure transducer under several centrifuge modeling environments is studied. The results indicate that the viscous drag ...
The paper describes some of the development work on the Cambridge University version of the self-boring pressuremeter (the so-called “Camkometer”), which has been carried out at the University of Western Australia over a number of years. This work included improvement of the pore-pressure measuring system and development of a deairing system for the pore-pressure transducers, new supply-voltage ...
A study of the response time of miniature pore pressure transducers embedded in clay soils is presented. The highly nonuniform pore pressure distributions around the transducers due to arching and stress concentration can have a significant effect on transducer response especially when the surrounding soil is loaded anisotropically. This is caused by the difference in compressibility of the soil ...
Attributes of the remote measurement of piezometric water pressure and water level with time domain reflectometry (TDR) techniques are investigated. The evaluation includes a two-wire system for unusually small riser tubes as well as parallel wire and air-filled or hollow coaxial cable for typical installations. Comparison of TDR cable and commercial pressure transducer technology shows coaxial ...
There are numerous different types of pressure sensing devices, with names that can be confusing to the uninformed and uninitiated. All of these terms are specific to variable capacitive sensing technologies, which handle the detection and measurement of fluid pressure through the change in voltage across a capacitor. Variable capacitance is used in applications that need an extremely high degree ...
Recently, I learned that certain smartphones contain an actual pressure transducer. I shared this info with a friend who insisted that the phone was not really measuring pressure, but was instead using the internet to download the pressure based on the phone’s location. Now, I had to prove them wrong. So, I did what I thought was the obvious proof… I placed my phone in a small test ...
Desirable requirements for volume capacity and precision of volume change devices for triaxial testing are studied, and operational requirements for devices suitable for automatic datalogging are reviewed. Two devices that fulfill these requirements have been constructed by the writer by combining existing design principles. One device consists of a buret system with differential pressure ...
A finite strain consolidation test with a constant surcharge to determine the compressibility (e - s') and permeability (e - k) relationships of very soft clay is proposed. The method uses Gammarays and pore pressure transducers to measure density and pore pressure profiles, respectively, at various times of the test without hindering the consolidation process. The constant surcharge applied ...
In February we introduced our newest submersible pressure transducer, the Series PT-510. The Series PT-510 is an OEM-ready submersible transducer, with a maximum depth of 46 feet. Today, let’s look at three specific advantages of using the PT-510 in well water measurement. The size of the PT-510 is its first advantage in well water measurement. At less than an inch (0.9” / 21.9 mm) ...
The Lasair III Aerosol Particle Counter is the latest generation of aerosol particle counter from Particle Measuring Systems. The Aerosol Manifold II is designed to work with the Lasair III counter under the control of Particle Measuring Systems facility monitoring software (Facility Net). The Lasair III particle counter uses a patented pressure measurement system to avoid the undercounting ...
OBTAINING SUPERIOR WATER LEVEL ACCURACY IN COASTAL ENVIRONMENTS In-Situ Inc. water level instruments measure the sum of all pressures (atmospheric and hydrostatic) exerted on a pressure transducer and use that data to calculate water levels. Water density contributes to the total hydrostatic pressure. Saltwater has a higher specific gravity than fresh water. A standard column of saltwater exerts ...
Romtec Utilities designs, manufactures, and supplies pumping systems for many different applications. Our systems include all structural, all mechanical, all electrical, and all communications systems in a single purchase. Many of our systems are designed and supplied to handle sewage and wastewater flows in a lift station design. In many scenarios, these lift stations are for new ...
This paper describes the design, calibration, and field performance of a number of new instruments that have been used for research into the behavior of displacement piles in clays and sand. The instruments include axial load cells, surface stress transducers, and pore pressure probes. The special features of the surface stress transducers and pore pressure probes are described in detail, and ...
A multi-sensor piezometer has been developed to measure dynamic excess and ambient pore pressures in shallow marine sediments under the effect of surface waves, tides, and currents. The probe consists of a shaft (1.5 m long with five porous stones at subseafloor depths ranging from 0.10 to 0.93 m) and two upper chambers (one that is hermetically sealed for the transducer electronics and another ...
Understanding soil water dynamics and accurately estimating groundwater recharge are essential steps in achieving efficient and sustainable management of groundwater resources in regions with deep vadose zones. The objective of this study was to understand transient data and the dynamics nature of water from deep sections at the thick vadose zone, and to estimate groundwater recharge by ...
How They Work A specific gas blend within a chamber must be produced by a procedure known as ideal gas mixing (or gas blending). In this example, synthetic air composition is maintained at a mix ratio of 78% N2, 21% O2 and 1% Ar. A miniature Human/Machine Interface (HMI) with LCD touch screen monitors and controls the system automatically. The HMI communicates to three SmartTrak 2 mass ...
Mass flow meters reduce risk of measurement error and provide a reliable, quantitative measurement of product quality and production process control. In the leak testing application, mass flow meters offer advantages unmatched by other instruments. Today, leak testing must be not only precise, accurate and irrefutable, but also easy-to-use, fast and efficient. With mass flow sensing, dry air ...
Leading the way for hydrant verification flow and pressure measurement Langham Industrial Controls strive to provide the most innovative market leading hydrant verification instrumentation. The Horizontal Standpipe Flow Meter provides unrivalled accuracy of ± 0.5% within a wide flow range. The swan neck design ensures that the AquaMasters electromagnetic sensor is always full and as the ...
Our range of hydrant flow test equipment offers many benefits that provide data that you can rely on. Here are 10 reasons why. 1. Record flow at an unrivalled accuracy of within 0.5% over a wide flow range. 2. Monitor static and/or running pressure with an optional remote pressure transducer. 3. Log flow and pressure on up to three integrated data loggers. Review and manage your ...
Overview Low emission pneumatic controllers and overall carbon footprint reduction are today's hot topics for electro-pneumatic control systems. As shown in the chart below, pneumatic controllers have been viewed as a significant source of greenhouse gas emissions!. Since natural gas is often an abundant pressure source, it is common practice to tap this gas as the supply for the pneumatic ...