EXPERIMENTAL AND NUMERICAL ANALYSIS OF HOT WATER BOILER IN START UP REGIME
2021
Аутори
Rajić, MilenaŽivković, Dragoljub
Banić, Milan
Mančić, Marko
Mitrović, Nenad
Milošević, Miloš
Конференцијски прилог (Објављена верзија)
Метаподаци
Приказ свих података о документуАпстракт
The aim of the paper is to investigate the transient regime of hot water boiler numerically and experimentally. In the regime of starting up, as the most critical one, measurements were done on the boiler critical element. The operating characteristics as well as safe and reliable operation conditions of hot water boilers are limited by thermal stresses that occur in their structure. The greatest thermal stresses occur in transient operating regimes such as starting-up, changing operation mode or sudden shutdown, resulting in uneven heating or cooling of boiler elements. Large temperature gradients cause high thermal stresses that are especially critical
in elements with thick walls. As thermal stresses may limit the heating and cooling rates of temperature changes, boiler structure is exposed to variable temperature and stress field. The largest absolute value of thermal stresses occurs at the inner surface, where direct measurements are not possible to take, since the inner surface ...is in direct contact with hot water under high pressure. This was the reason to measure the temperature of boiler structure inside the boiler, on tube plate, as one of the critical part of the boiler. In this paper the experimental results of temperature measurement of tube plate were presented, during the regime of starting-up. Numerical model done by FEM was verified by experimental results. The performed analysis showed that the tube plate of the first reversing chamber, the boiler element with the thickest wall, is exposed to the highest thermal stresses. This part of the boiler is exposed to temperatures
t>500 ℃ and it is exposed to creep. In conditions of creep, continuous accumulation of plastic deformations occurs at a rate that depends on the level of stress, temperature and material characteristics.
Кључне речи:
Hot Water Boiler / Start up / Thermal stresses / Experimental measurements / FEMИзвор:
International Conference of Experimental and Numerical Investigations and New Technologies CNN TECH 2021, 07-2021, 30-Издавач:
- Innovation Center of Faculty of Mechanical Engineering
Колекције
Институција/група
Mašinski fakultetTY - CONF AU - Rajić, Milena AU - Živković, Dragoljub AU - Banić, Milan AU - Mančić, Marko AU - Mitrović, Nenad AU - Milošević, Miloš PY - 2021-07 UR - https://machinery.mas.bg.ac.rs/handle/123456789/7697 AB - The aim of the paper is to investigate the transient regime of hot water boiler numerically and experimentally. In the regime of starting up, as the most critical one, measurements were done on the boiler critical element. The operating characteristics as well as safe and reliable operation conditions of hot water boilers are limited by thermal stresses that occur in their structure. The greatest thermal stresses occur in transient operating regimes such as starting-up, changing operation mode or sudden shutdown, resulting in uneven heating or cooling of boiler elements. Large temperature gradients cause high thermal stresses that are especially critical in elements with thick walls. As thermal stresses may limit the heating and cooling rates of temperature changes, boiler structure is exposed to variable temperature and stress field. The largest absolute value of thermal stresses occurs at the inner surface, where direct measurements are not possible to take, since the inner surface is in direct contact with hot water under high pressure. This was the reason to measure the temperature of boiler structure inside the boiler, on tube plate, as one of the critical part of the boiler. In this paper the experimental results of temperature measurement of tube plate were presented, during the regime of starting-up. Numerical model done by FEM was verified by experimental results. The performed analysis showed that the tube plate of the first reversing chamber, the boiler element with the thickest wall, is exposed to the highest thermal stresses. This part of the boiler is exposed to temperatures t>500 ℃ and it is exposed to creep. In conditions of creep, continuous accumulation of plastic deformations occurs at a rate that depends on the level of stress, temperature and material characteristics. PB - Innovation Center of Faculty of Mechanical Engineering C3 - International Conference of Experimental and Numerical Investigations and New Technologies CNN TECH 2021 T1 - EXPERIMENTAL AND NUMERICAL ANALYSIS OF HOT WATER BOILER IN START UP REGIME SP - 30 UR - https://hdl.handle.net/21.15107/rcub_machinery_7697 ER -
@conference{ author = "Rajić, Milena and Živković, Dragoljub and Banić, Milan and Mančić, Marko and Mitrović, Nenad and Milošević, Miloš", year = "2021-07", abstract = "The aim of the paper is to investigate the transient regime of hot water boiler numerically and experimentally. In the regime of starting up, as the most critical one, measurements were done on the boiler critical element. The operating characteristics as well as safe and reliable operation conditions of hot water boilers are limited by thermal stresses that occur in their structure. The greatest thermal stresses occur in transient operating regimes such as starting-up, changing operation mode or sudden shutdown, resulting in uneven heating or cooling of boiler elements. Large temperature gradients cause high thermal stresses that are especially critical in elements with thick walls. As thermal stresses may limit the heating and cooling rates of temperature changes, boiler structure is exposed to variable temperature and stress field. The largest absolute value of thermal stresses occurs at the inner surface, where direct measurements are not possible to take, since the inner surface is in direct contact with hot water under high pressure. This was the reason to measure the temperature of boiler structure inside the boiler, on tube plate, as one of the critical part of the boiler. In this paper the experimental results of temperature measurement of tube plate were presented, during the regime of starting-up. Numerical model done by FEM was verified by experimental results. The performed analysis showed that the tube plate of the first reversing chamber, the boiler element with the thickest wall, is exposed to the highest thermal stresses. This part of the boiler is exposed to temperatures t>500 ℃ and it is exposed to creep. In conditions of creep, continuous accumulation of plastic deformations occurs at a rate that depends on the level of stress, temperature and material characteristics.", publisher = "Innovation Center of Faculty of Mechanical Engineering", journal = "International Conference of Experimental and Numerical Investigations and New Technologies CNN TECH 2021", title = "EXPERIMENTAL AND NUMERICAL ANALYSIS OF HOT WATER BOILER IN START UP REGIME", pages = "30", url = "https://hdl.handle.net/21.15107/rcub_machinery_7697" }
Rajić, M., Živković, D., Banić, M., Mančić, M., Mitrović, N.,& Milošević, M.. (2021-07). EXPERIMENTAL AND NUMERICAL ANALYSIS OF HOT WATER BOILER IN START UP REGIME. in International Conference of Experimental and Numerical Investigations and New Technologies CNN TECH 2021 Innovation Center of Faculty of Mechanical Engineering., 30. https://hdl.handle.net/21.15107/rcub_machinery_7697
Rajić M, Živković D, Banić M, Mančić M, Mitrović N, Milošević M. EXPERIMENTAL AND NUMERICAL ANALYSIS OF HOT WATER BOILER IN START UP REGIME. in International Conference of Experimental and Numerical Investigations and New Technologies CNN TECH 2021. 2021;:30. https://hdl.handle.net/21.15107/rcub_machinery_7697 .
Rajić, Milena, Živković, Dragoljub, Banić, Milan, Mančić, Marko, Mitrović, Nenad, Milošević, Miloš, "EXPERIMENTAL AND NUMERICAL ANALYSIS OF HOT WATER BOILER IN START UP REGIME" in International Conference of Experimental and Numerical Investigations and New Technologies CNN TECH 2021 (2021-07):30, https://hdl.handle.net/21.15107/rcub_machinery_7697 .