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Zmodyfikowana akustyczna metoda wyznaczania temperatury w kotłach przemysłowych

Lozbin V., Wójcik W., Zhelazko G.

Pomiary Automatyka Kontrola

2007

R. 53, nr 11

34-37

W pracy przedstawiono modyfikację akustycznej metody wyznaczania przestrzennego rozkładu temperatury w kotłach energetycznych. W metodzie tej uwzględniony został wpływ składu chemicznego spalin oraz parametru termodynamicznego na wynik odwzorowania rozkładu pola temperatury w kotle, co spowodowało zmniejszenie błędów w porównaniu z jej klasyczną wersją.

In the work a modification of acoustic method for determination of spatial temperature distribution in power boilers is presented. An influence of chemical composition of flue gasses as well as the thermodynamic factor on the result of imaging of temperature field distribution in a boiler was taken into account, what resulted in error decrease comparing to the classical method.

Acoustic tomography of a turbulent water jet

Gavrilenko V., Didenkulov I., Kustov L., Martyanov A., Nechayeva M., Vyugin P., Pronchatov-Rubtsov N.

Hydroacoustics

2003

Vol. 6

91--100

Measurement of parameters of flowing liquid is one of problems, which have many applications. in the present paper we describe linear and nonlinear acoustic tomography methods for reconstruction of parameters of a turbulent water jet with gas bubbles. Experiments on both techniques are described. in the linear acoustic method it was measured fluctuations of acoustic signal passed through the jet. In the nonlinear acoustic technique it was measured spectra of combination scattering signals in the jet. Experiments were done in a water tank with a submerged water jet. The results of the work demonstrate the possibility of the tomography of flowing bubble liquids.

Zastosowanie tomografii akustycznej do wyznaczania rozkładu temperatury w kotle

Wach J.

Biuletyn Wojskowej Akademii Technicznej

2000

Vol. 49, nr 4

133-143

W artykule opisano tomograf akustyczny do pomiaru rozkładu pola temperatur w komorze paleniskowej. Zasada działania oparta jest na pomiarze czasuprzelotu fali akustycznej między wybranymi punktami zlokalizowanymi na obwodzie komory. W pracy przedstawiono wyniki rekonstrukcji pola temperatur na bazie pomiaru symulowanego komputerowo oraz rzeczywistego.

The paper shows a tomographic method for measurement of temperature distribution in combustion chamber. The principle idea is an acoustic time-of-flight measurement in a medium. Mounting a set of transceivers around combustion chambers in the selected plane one can measure the set of propagation times between every pair of the transceivers. Given a pair of transceivers determines the path of single ray. It is posible to reconstruct the spatial sound speed distribution across the plane using a tomographic algorithm. The temperature distribution T then can be calculated by the known speed of sound. To solve the problem the iterative ART-algorithm was used modified by Back Projection method. Simulations were performed for combustion chamber with square cross-section. A different transceiver layout has been used - 2, 3, 4 and 5 transceivers on each side. The symmetric and asymmetric temperature distribution was simulated using trigonometric and exponential function. Reconstructed the initial temperature distribution fits very well to assume one for each transceiver layout. The maximum pixel error in case of symmetric temperature field was found to be under 1.8% and 6% in case of asymmetric temperature field. The mean temperature was calculated to be between 1315 and 1340 K which differs from initial mean value by 4 ÷ 20 K. Also a stationary measurements have been carried out using a simple measurement unit. It consisted of two transceivers moving around the chamber during the measurement. The results show that such simple system can produce fairly good results.