Soil Water Flowmeters with Thermocouple Outputs

Tracking Natural Gas with Flowmeters

Reference Flowmeters

The most commonly used flowmeter is the orifice meter. The orifice meter consists of two parts. As shown in Figure 1, they are the measurement orifice plate, which is installed in the process line, and the differential pressure transmitter, which measures the pressure developed across the orifice plate. There has been extensive research to determine the operating characteristics of orifice meters.

Thermocouple Measurement

In 1822, Thomas Seebeck, an Estonian physician, accidentally joined semicircular pieces of bismuth and copper (Figure 1) while studying thermal effects on galvanic arrangements. A nearby compass indicated a magnetic disturbance. Seebeck experimented repeatedly with different metal combinations at various temperatures, noting relative magnetic fi eld strengths. Curiously, he did not believe that...

Errors in measuring water potentials of small samples resulting from water adsorption by thermocouple psychrometer chambers.

The adsorption of water by thermocouple psychrometer assemblies is known to cause errors in the determination of water potential. Experiments were conducted to evaluate the effect of sample size and psychrometer chamber volume on measured water potentials of leaf discs, leaf segments, and sodium chloride solutions. Reasonable agreement was found between soybean (Glycine max L. Merr.) leaf water...

Cross Correlation Flowmeters with Ae Sensors

This paper is concerned on the new type of the sensing elements for a particle volume of flow rate measurements based on cross correlation flowmeters. The new type of sensing elements exploit the fact that the solid particles being carried by a flowing air and impacting a properly formed obstacle generate an acoustic surface wave (acoustic emission AE). The acoustic signal is indicated by the a...