Vodní chlazení hliníkových slitin

Water jet cooling of aluminium alloy

článek ve sborníku ve WoS nebo Scopus

en

Jet cooling is used in many industrial applications. A typical application is the ingot casting process. Cooling water flows into a mold, where it is distributed through a system of channels into holes that are spaced very closely together. For better homogenization, the water flows from the leading edge and then impacts the surface of an aluminum ingot. [1] To obtain realistic results from numerical simulations, it is necessary to know the boundary conditions for each cooling scenario. It is not possible to use analytic solutions or multiphysics simulation software to obtain realistic heat transfer coefficient (HTC) curves which represent the cooling intensity. Boundary conditions can be obtained by experimentally reproducing the same conditions in the laboratory and measuring temperature dependence over time. Evaluating the data is done using the inverse task, which calculates the surface temperature and HTC. Temperatures are measured using shielded thermocouples which are installed very close to the sample surface. The final goal of this work is to experimentally investigate the cooling intensity during the casting process of ingots. Two types of cooling regime – continuous and pulse and changing the amount of cooling water were studied. The HTC curves from the calculated surface temperature data are used as boundary conditions for a numerical model which can simulate temperature distribution inside the ingot during the cooling process.

Chlazení paprskem vody se používá v mnoha průmyslových aplikacích. Typický příklad je chlazení při odlévání ingotů. Chladící vody proudí přes krystalizátor, kde je rozváděna pomocí systému kanálků na náběžnou plochu, která má funkci homogenizátoru proudící vody. K získání reálných výsledků ze simulování chlazení ingotů je nutné znát přesnou okrajovou podmínku pro jednotlivé scénáře chlazení. V tomto případě není možné použít analytické řešení nebo komerční softwary pro získání reálného průběhu koeficientu přestupu tepla (HTC), který by reprezentoval chladící efekt vody. Okrajové podmínky, jsou získávány z experimentů, kde jsou nastaveny stejné podmínky, jaké jsou při licím procesu. Naměřené data (teploty na čase) jsou přepočítána pomocí vyvinutého softwaru využívající inverzní úlohu na povrchové hodnoty (HTC na povrchové teplotě). Dva typy chladících režimů – průběžné, pulzní a různé průtoky byly zkoumány.

Jet cooling is used in many industrial applications. A typical application is the ingot casting process. Cooling water flows into a mold, where it is distributed through a system of channels into holes that are spaced very closely together. For better homogenization, the water flows from the leading edge and then impacts the surface of an aluminum ingot. [1] To obtain realistic results from numerical simulations, it is necessary to know the boundary conditions for each cooling scenario. It is not possible to use analytic solutions or multiphysics simulation software to obtain realistic heat transfer coefficient (HTC) curves which represent the cooling intensity. Boundary conditions can be obtained by experimentally reproducing the same conditions in the laboratory and measuring temperature dependence over time. Evaluating the data is done using the inverse task, which calculates the surface temperature and HTC. Temperatures are measured using shielded thermocouples which are installed very close to the sample surface. The final goal of this work is to experimentally investigate the cooling intensity during the casting process of ingots. Two types of cooling regime – continuous and pulse and changing the amount of cooling water were studied. The HTC curves from the calculated surface temperature data are used as boundary conditions for a numerical model which can simulate temperature distribution inside the ingot during the cooling process.

odlévání hliníkových slitin, koeficient přestupu tepla, inverzní úloha, termočlánky

aluminum casting process, heat transfer coefficient, inverse task, thermocouples

2015

03.06.2015

TANGER Ltd.

Ostrava

978-80-87294-58-1

METAL 2015, 24rd International Conference on Metallurgy and Materials, Conference Proceedings

1439–1444

6