CONVECTIVE HEAT TRANSFER IN A GAS-FIRED HEAT TREATMENT FURNACE

1994 ◽  
Author(s):  
J. L. V. A. Sousa ◽  
John Ward ◽  
R. J. Tucker
Keyword(s):  
Heat Transfer ◽  
Heat Treatment ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Heat Treatment Furnace ◽  
Treatment Furnace

STUDY OF HEAT TRANSFER CHARACTERISTICS OF LAMINATED STEEL HEAT TREATMENT FURNACE

2020 ◽  
Vol 51 (8) ◽  
pp. 707-721
Author(s):  
Zuohan Liu ◽  
Zhi Wen ◽  
Ruifeng Dou ◽  
Fuyong Su ◽  
Tianhua Xie
Keyword(s):  
Heat Transfer ◽  
Heat Treatment ◽  
Heat Transfer Characteristics ◽  
Heat Treatment Furnace ◽  
Transfer Characteristics ◽  
Treatment Furnace ◽  
Steel Heat

scholarly journals EXPERIMENTAL STUDY OF THE INFLUENCE OF TEMPERATURE ON PASTEURIZATION OF PÊRA RIO IN NATURA ORANGE JUICE

2022 ◽  
Author(s):  
Gabriela Regina Rosa GALIASSI ◽  
◽  
Maribel Valverde RAMIREZ
Keyword(s):  
Heat Transfer ◽  
Heat Treatment ◽  
Heat Transfer Coefficient ◽  
Vitamin C ◽  
Transfer Coefficient ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Orange Juice ◽  
Convective Heat Transfer Coefficient ◽  
Fast Heating

Heat treatment is one of the most used methods to preserve food, such as orange juices, which are an excellent source of ascorbic acid. To avoid vitamin C degradation and reduce loss, fast heating is recommended. This work aimed to determine the vitamin C content using the iodometric method and the convective heat transfer coefficient using the method of dimensionless numbers and the experimental method. Time and temperature were controlled throughout the experiment. In pasteurization, the solution was heated to 80 °C, heating lasted 50 minutes and cooling for 42 minutes. The convective heat transfer coefficient was evaluated in two regions of the cylindrical container: near the wall and in the central region. The graphic profile of the curve follows the same trend of the literature. The convective heat transfer coefficient is higher in the region near the wall. As time passes and temperature decreases, the central region tends to equilibrium, and the coefficient becomes more constant. The vitamin C content remained constant before and after pasteurization, so it was observed that the pasteurization did not cause ascorbic acid degradation since the heating step was fast in the heat treatment. As a result of the study, it was noted that studying the thermal behavior in the cooling of orange juice is extremely important to ensure its quality. It is pertinent to mention that in order to avoid this degradation and reduce its loss, it is necessary that in thermal treatments, fast heating is carried out and that the juice has low exposure to air and heat at the time of its preparation.

Numerical Analysis of the Heat Transfer Through a Heat Treatment Furnace

2017 ◽  
Author(s):  
Kesiany Máxima de Souza ◽  
Felipe Barbosa ◽  
Olexiy Shynkarenko ◽  
Paulo Gabriel Cunha Martins
Keyword(s):  
Heat Transfer ◽  
Heat Treatment ◽  
Numerical Analysis ◽  
Heat Treatment Furnace ◽  
Treatment Furnace

scholarly journals Investigation of the migration of the least heating zone of clarified apple juice during heat treatment

2020 ◽  
Vol 82 (1) ◽  
pp. 88-95
Author(s):  
V. V. Kondratenko ◽  
B. L. Kanevskiy ◽  
G. P. Pokudina ◽  
L. A. Borchenkova ◽  
V. I. Senkevich
Keyword(s):  
Heat Transfer ◽  
Heat Treatment ◽  
Rheological Properties ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Apple Juice ◽  
Vertical Axis ◽  
Heating Zone ◽  
Thermal Sterilization ◽  
Object Of Study

When developing modes of food products thermal sterilization, it is necessary to determine the conditions for microorganisms test cultures and their spores guaranteed death in the least heating zone. The location of this zone is a critical parameter in thermal processes. At present, there are conflicting ideas about the localization and possible migration of the zone of least heating in the process of thermal sterilization of products with convective heat transfer. The kinetics of localization of the zone of least heating in the medium volume with convective heat transfer during heat treatment in conjunction with rheological properties was studied in the work. The clarified apple juice for baby food of domestic production was used as the object of study. The probe was placed so that the thermocouple was located on the vertical axis of the can at a geometric height of 3, 6, 9, 12, 18 and 24 mm. At each height value of the thermocouple, the jar with the sample was thermostated for 20 minutes, and then quickly cooled for 10 minutes. Heating was carried out at a thermostat temperature of 75, 80, 85, 90, and 95°C. The dynamics of rheological properties under isothermal conditions at temperatures of 30, 35, 40, 45, 50, 55, and 60°C and a range of shear rates from 0 to 700 s – 1 were also studied in the samples. As a result of the studies carried out, the presence of the migration of the zone of least heating during the heat treatment of single-phase media with convective heat transfer was determined experimentally, its kinetics was studied, the non-linear and reversible nature of the migration of the zone of least heating was established. The mechanism of the process of migration of the zone of least heating was proposed taking into account the dynamics of the rheology of the heated medium and the convective flows interaction.

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