Title :
Enhanced Local Void and Temperature Measurements for Highly Transient Two-Phase Flows
Author :
Schleicher, Eckhard ; Silva, Marco Jose Da ; Hampel, Uwe
Author_Institution :
Exp. Thermo fluid dynamics Div., Inst. of Safety Res., Dresden
Abstract :
We introduce a novel combined temperature and conductivity needle probe measuring system for local void fraction measurements in two-phase flow experiments. The system is able to deal with direct sheathed micro thermocouples as well as open thermocouples. It consists of a thermo needle probe connected to a special electronic circuit using AC measuring technique for the conductivity measurements and a high gain instrumentation amplifier with very high common mode rejection for the amplification of the Seebeck voltage generated by the micro thermocouple. After system build up and calibration, the system has been tested in different experiments. In a dropping experiment the time constant of the temperature measurement of the needle probe system was determined as 3.6 ms. Additionally, steam-water experiments have been carried out to demonstrate the system performance
Keywords :
Seebeck effect; electrical conductivity measurement; instrumentation amplifiers; temperature measurement; thermocouples; two-phase flow; AC measuring technique; Seebeck voltage; conductivity measurements; high gain instrumentation amplifier; local void fraction measurements; microthermocouples; needle probe measuring system; temperature measurements; thermo needle probe; two-phase flow experiments; AC generators; Conductivity measurement; Electronic circuits; Fluid flow measurement; Gain measurement; Instruments; Needles; Probes; Temperature measurement; Voltage; micro-thermocouple; needle probe; temperature measurement; two-phase flows;
Conference_Titel :
Instrumentation and Measurement Technology Conference, 2006. IMTC 2006. Proceedings of the IEEE
Conference_Location :
Sorrento
Print_ISBN :
0-7803-9359-7
Electronic_ISBN :
1091-5281
DOI :
10.1109/IMTC.2006.328630
