A transfer standard for flowmeter calibration provides traceability to a primary standard. It is typically used for most commercial calibrations because it represents an economically attractive alternative to a primary system. A set of critical flow venturi (CFV) transfer standards have been maintained in calibration at CEESI for the past 35 years. The uncertainty in mass flowrate has been esti...

Cross-borehole flowmeter tests have been proposed as an efficient method to investigate preferential flowpaths in heterogeneous aquifers, which is a major task in the characterization of fractured aquifers. Cross-borehole flowmeter tests are based on the idea that changing the pumping conditions in a given aquifer will modify the hydraulic head distribution in large-scale flowpaths, producing m...

We report here a novel two-mode mass flowmeter that can be operated in either thermal or differential pressure mode. By combining these two complementary operating principles, the performance can be improved significantly. This flowmeter is based on a multi-sensor chip that includes a 1-D array of shear stress, pressure and temperature sensors. The multi-sensor chip can also be employed in many...

Critical measurement performance of fluid flowmeters requires proper and quantified verification data. These data should be generated using calibration and traceability techniques established for these verification purposes. In these calibration techniques, the calibration facility should be well-characterized and its components and performance properly traced to pertinent higher standards. The...

Oxygen therapy besides having benefits also has certain dangers and side effects. For this reason, oxygen must be given at the proper dose by monitoring patient regularly adjusting flowmeter. The accuracy of flowmeter under standard conditions is guaranteed manufacturer. With time use precision may change flow in a hospital setting differ from original value. Thepurpose research to conduct furt...

Electromagnetic flowmeters are used to measure the speed of water flow in water distribution systems. Corrosion problem in metal pipelines can be solved by cathodic protection methods. This paper presents a research on corruptive effects of the cathodic protection system on electromagnetic flowmeter depending on its measuring principle. Experimental measurements are realized on the water distri...

The measurement principle of the transit time difference method of the ultrasonic flowmeter is presented. The hardware structure and realization method are introduced. The software function and work mode are overviewed. In order to enhancing flowmeter's precision and stability a Xilinx CoolRunner CPLD and a Texas Instruments microcontroller from MSP430 family are applied in high precision timin...