Eventos Anais de eventos
ENCIT 2018
Brazilian Congress of Thermal Sciences and Engineering
ENERGY OPTIMIZATION OF EXPERIMENTAL BENCH TEST FOR STUDY OF INTERNAL HEAT TRANSFER COEFICIENT IN QUENCHING BY IMMERSION OF TUBES
Submission Author:
Kássio Nogueira Cançado , MG
Co-Authors:
Kássio Nogueira Cançado, Ricardo Poley Martins Ferreira, Luiz Machado, Juan Jose Garcia Pabon, Lis Nunes Soares
Presenter: Kássio Nogueira Cançado
doi://10.26678/ABCM.ENCIT2018.CIT18-0534
Abstract
The quenching process is fundamental to the final quality of steel tubes. Experiments on quenching processes are costly and time-consuming. Numerical simulations allow to reduce the time and costs of these studies. However, they are limited by the uncertainty arising from the heat transfer coefficient between the water and the tube surface. The internal heat transfer coefficient can be determined experimentally, however the size of the industrial quenching processes prevent the realization of a real scale test. A test bank can be used to determine the heat transfer coefficient by similarity (Buckingham's Theorem). The main limitation of this type of test bench is power required by the system. This problem can be solved with the use of organic fluids. This work aims to select an organic fluid that allows the maximization of the dimensions of the tube diameter used in the bench test with the minimization of the energy consumed by the same. An optimization by genetic algorithm type will determine the fluid that best adapt to proposed experiment. The correct selection of the working fluid will allow the use of the test bench for a greater number of conditions, increasing the results accuracy. The best performing organic fluid was the pentane which a pressure drop of 3 bar and a power demand of 21.4 kW. Compared to R236fa, which presented the worst result (7.7 bar and 24 kW), the optimization of the working fluid allowed a reduction of 156% in the pressure drop and 12% in the power demand. When compared to water (8 bar and 192 kW), the use of optimized organic fluid allowed a reduction of 166% in the pressure drop and 797% in the power demand, enabling assembly and reducing the cost of equipment
Keywords
quenching, Heat Transfer Coefficiente, Optimization Energy, Similarity Analysis
