Showing papers on "Thermal mass flow meter published in 2018"

Accuracy of single-jet and multi-jet water meters under the influence of the filling process in intermittently operated pipe networks

Abstract: In many areas of the world water distribution systems are operated intermittently. The alternate filling and emptying of the pipe network leads to effects, which have negative impacts on water meter accuracy. For example, air that is present in the pipe network due to the emptying process must exit the network during the subsequent filling process. A part of this air is discharged through service connections and, thus, through water meters. In this paper, a study is presented in which the measurement error of single-jet and multi-jet water meters due to the filling process of an empty pipe is investigated experimentally. From the start of air flow to the steady-state flow of water, several causes of measurement errors can be distinguished, such as pure air flow, the impact of the water front on the impeller, the existence of two-phase flow or unsteady flow conditions. For both meter types, it has been discovered that the measurement error is mainly caused by the air flow. The experimental results show that up to 93% of the air volume in the pipe is registered by the water meters. Based on these results, an approach for estimating the measurement error for both meter types is presented.

Thermal mass flow meter and Thermal mass flow measurement system

Abstract: The present invention relates to a thermal mass flow meter which is able to measure a flow of a medium flowing in a pipe in a dry type without cutting the pipe, comprising: a heating device heating at least a part of an interior medium of the pipe from the outside of the pipe; a first temperature measuring device formed in a first location which is the front of a flowing direction of the medium in a basis of the heating device such that temperature distribution in accordance with a fluid velocity of the medium heated in the pipe by the heating device can be measured from the outside of the pipe; and a second temperature measuring device formed to be symmetrical with the first temperature measuring device in a second location which is the rear of the flowing direction of the medium in a basis of the heating device such that temperature distribution in accordance with a fluid velocity of the medium heated in the pipe by the heating device can be measured from the outside of the pipe.

Three-phase metering device and method for production liquid of pipeline-type high-water-content oil well

Abstract: The invention discloses a three-phase metering device and method for production liquid of a pipeline-type high-water-content oil well. The device comprises a swirling flow device, a gas core samplingpipe, an oil-water homogenizer, a water content measuring system and a flow measuring system which are sequentially connected to a main pipeline from bottom to top, and a gas-liquid swirling flow separator is arranged in the gas core sampling pipe. By means of the three-phase metering device and method, a gas phase and oil and water liquid phases of the production liquid are separated, separated gas is led out through a special pipe, and the mass of the gas is accurately measured by adopting a differential pressure or thermal mass flow meter and the like; for oil-water mixed fluid after passing through the homogenizer, water can become a continuous phase, oil can become a free phase dispersed in the water, the water content can be measured by adopting a capacitor under the high-water-content condition, then the fluid flows through a flow measurement area where an electromagnetism, acoustic wave or ray mode is adopted at the rear end to achieve flow measurement, and in combination withthe water content parameter and temperature and pressure measurement results, the mass flow of the water of the production liquid and the mass flow of the oil of the production liquid are measured.

Design of a Thermal Mass Flow Meter for Measurements Within the Rotor Rim Ducts of a Hydroelectric Generator

Abstract: To ensure the proper operation of hydroelectric generators, their cooling must be well understood. However, the airflow within such machines is difficult to characterize, and although Computational Fluid Dynamics (CFD) can be a reliable engineering tool, its application to the field of hydroelectric generators is quite recent and has certain limitations which are, in part, due to geometrical and flow complexities, including the coexistence of moving (rotor) and stationary (stator) components. For this reason, experimental measurements are required to validate CFD simulations of such complex flows. Of particular interest is the quantification of the flow within the rotor rim ducts, since it is directly responsible for cooling the poles (one of the most critical components of a hydroelectric generator). Thus, to measure the flow therein, an anemometer was designed. The anemometer had to be accurate, durable, cost-effective, easy to install, and able to withstand the extreme conditions found in hydroelectric generators (temperatures of 45°C, centrifugal forces of 300 g, etc.). In this paper, a thermal mass flow meter and a method for validating its performance, using hot-wire anemometry and a static model of a rotor rim, are described. Preliminary tests demonstrate that the thermal mass flow meter is capable of i) measuring the mass flow rate in the rotor rim ducts with an accuracy of approximately 10%, ii) fitting inside small rectangular ducts (12.2 mm by 51 mm), and iii) resisting forces up to 300 g.

Method for operating multiple neighbouring magnetic-inductive flow meters and arrangement of multiple neighbouring magnetic-inductive flow meters

Abstract: The method involves preventing variations of mutual influences (5) caused on flow rate measurements by magnetic fields of adjacently arranged master magnetic-inductive volumetric flow meter (1a) and slave magnetic-inductive volumetric flow meters (1b-1d) by synchronizing individual measurement processes of the flow meters to perform a synchronous measurement process. The magnetic field is produced by a magnetic field generating device of single flow meter during the individual measurement process. The measurement processes are controlled by one of the flow meters. An independent claim is also included for an arrangement of adjacently arranged magnetic-inductive volumetric flow meters.

Thermal mass flow meter

Abstract: Provided is a thermal mass flow meter comprising: a first measurement pipe (12) which has an inlet (E1) and an outlet (S1) connected to a main pipe and which is provided with two temperature sensors and means for heating the fluid between two sensors; a deprimogenic member (14); a pressure measuring device (17) for producing differential pressure measurements in the main pipeline between an upstream point and a downstream point located respectively upstream and downstream of the pressure reducing member (14); a processing unit connected to the temperature sensors for producing flow measurements from temperature measurements produced by the temperature sensors and the pressure measuring device for correcting the flow measurements as a function of the differential pressure measurements. A method for measuring a flow rate is also provided.