Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Química, Florianópolis, 2009 / Made available in DSpace on 2012-10-24T12:54:25Z (GMT). No. of bitstreams: 1
278410.pdf: 4531823 bytes, checksum: 2b7956f473c263b41f571a121e9409d8 (MD5) / Esta investigação científica tem por objetivo o desenvolvimento de uma metodologia computacional capaz de simular e diagnosticar os perfis de temperatura e umidade em regime transiente durante a secagem de um produto cárneo. As simulações tridimensionais desenvolvidas envolveram as equações de transporte: conservação da massa, quantidade de movimento e transferência de energia. Este trabalho esta dividido em três etapas: na primeira etapa simulações numéricas utilizando fluidodinâmica computacional (CFD) foram realizadas para predizer as transferências de calor e massa durante o processo de secagem da linguiça calabresa em secador tipo túnel. Calcularam-se os coeficientes convectivos superficiais de transferência de calor e massa para a linguiça calabresa. O modelo permitiu prever as distribuições de temperatura e umidade no produto, e os resultados obtidos estavam de acordo com dados experimentais. A segunda etapa objetivou a predição do fluxo tridimensional isotérmico do ar em um forno industrial piloto de convecção forçada. O modelo CFD utilizado considera as equações da continuidade da massa, da quantidade de movimento e o modelo de turbulência .-e. O desempenho do modelo CFD foi avaliado por meio de medições pontuais de velocidade com um sensor de filme quente, sendo que os resultados simulados foram próximos às medições reais de velocidade do forno industrial. Com base nas etapas anteriores, a terceira etapa caracterizou-se pela secagem de um conjunto de trinta peças de linguiça calabresa no forno industrial piloto. O fluxo externo e os campos de temperatura foram determinados pelo pacote comercial Ansys-CFX®. A partir destas distribuições, determinaram-se os coeficientes superficiais de transferência de calor por convecção e com analogia entre as camadas limites térmica e de concentração, os coeficientes de transferência de massa. Além disso, utilizou-se o código desenvolvido para determinar as transferências de calor e massa para a obtenção das distribuições de temperatura e umidade na parte interna do produto ao longo do tempo. Os resultados obtidos a partir da presente análise foram comparados com os dados experimentais, e uma boa concordância foi observada. Os principais resultados demonstram que as metodologias empregadas, baseadas nas técnicas de CFD, estão aptas a reproduzir o comportamento fenomenológico das condições de secagem estudadas. / The objective this scientific investigation is the developement of a computational methodology that is able to simulate the transient profile of temperature and moisture during drying of meat product. The three-dimension simulation developed included the transport equations: mass, momentum and energy conservation. This work is organised in three steps: in the first step numerical simulation using computational fluid dinamics (CFD) were conducted to predict a couple heat and mass transfer during drying tunnel process of a calabresa sausage. The local heat and mass transfer coefficients were calculated around the calabresa sausage. The model allows calculating and predicting the temperatures and moisture content that agree with experimental data. The aim of second step, were predict the isothermal tri-dimensional air flow in the industrail forced-convection oven. The CFD model consists of the continuity, momentum and standard ê-å approach to model the turbulence flow. The performance of the CFD model was assessed by means of point measurements of the velocity with a hot-film anemometer sensor and a good agreement of the 3D flow pattern in a forced convection oven was found. Based ond the previous steps, the third step was characterized by drying of a set thirty pieces of calabresa sausage in industrial oven. The external flow and temperature fields are first numerically predicted through the comercial Ansys-CFX® package. From these distribuitions, the local distribuitions of convective heat transfer coefficients are determined, wich then used to predict local distribuitions of the convective mass transfer coefficients through the analogy between the thermal and concentration boundary layers. Also, the temperature and moisture distribuitions for different periods of time are obtained using the code developed to determine heat and mass transfer inside the moist material. The results obtained from the present analysis are comapoared with the experimental data, and a good agreement was observed. The main results demonstrated that the methodology, based on CFD techniques, was able to reproduce the phenomenological behavior of drying.The objective this scientific investigation is the developement of a
computational methodology that is able to simulate the transient profile of temperature and moisture during drying of meat product. The three-dimension simulation developed included the transport equations: mass, momentum and energy conservation. This work is organised in three steps: in the first step numerical simulation using computational fluid dinamics (CFD) were conducted to predict a couple heat and mass transfer during drying tunnel process of a calabresa sausage. The local heat and mass transfer coefficients were calculated around the calabresa sausage. The model allows calculating and predicting the temperatures and moisture content that agree with experimental data. The aim of second step, were predict the isothermal tri-dimensional air flow in the industrail forced-convection oven. The CFD model consists of the continuity, momentum and standard ê-å approach to model the turbulence flow. The performance of the CFD model was assessed by means of point measurements of the velocity with a hot-film anemometer sensor and a good agreement of the 3D flow pattern in a forced convection oven was found. Based ond the previous steps, the third step was characterized by drying of a set thirty pieces of calabresa sausage in industrial oven. The external flow and temperature fields are first numerically predicted through the comercial Ansys-CFX® package. From these distribuitions, the local distribuitions of convective heat transfer coefficients are determined, wich then used to predict local distribuitions of the convective mass transfer coefficients through the analogy between the thermal and concentration boundary layers. Also, the temperature and moisture distribuitions for different periods of time are obtained using the code developed to determine heat and mass transfer inside the moist material. The results obtained from the present analysis are comapoared with the experimental data, and a good agreement was observed. The main results demonstrated that the methodology, based on CFD techniques, was able to reproduce the phenomenological behavior of drying.The objective this scientific investigation is the developement of a
computational methodology that is able to simulate the transient profile of temperature and moisture during drying of meat product. The three-dimension simulation developed included the transport equations: mass, momentum and energy conservation. This work is organised in three steps: in the first step numerical simulation using computational fluid dinamics (CFD) were conducted to predict a couple heat and mass transfer during drying tunnel process of a calabresa sausage. The local heat and mass transfer coefficients were calculated around the calabresa sausage. The model allows calculating and predicting the temperatures and moisture content that agree with experimental data. The aim of second step, were predict the isothermal tri-dimensional air flow in the industrail forced-convection oven. The CFD model consists of the continuity, momentum and standard ê-å approach to model the turbulence flow. The performance of the CFD model was assessed by means of point measurements of the velocity with a hot-film anemometer sensor and a good agreement of the 3D flow pattern in a forced convection oven was found. Based ond the previous steps, the third step was characterized by drying of a set thirty pieces of calabresa sausage in industrial oven. The external flow and temperature fields are first numerically predicted through the comercial Ansys-CFX® package. From these distribuitions, the local distribuitions of convective heat transfer coefficients are determined, wich then used to predict local distribuitions of the convective mass transfer coefficients through the analogy between the thermal and concentration boundary layers. Also, the temperature and moisture distribuitions for different periods of time are obtained using the code developed to determine heat and mass transfer inside the moist material. The results obtained from the present analysis are comapoared with the experimental data, and a good agreement was observed. The main results demonstrated that the methodology, based on CFD techniques, was able to reproduce the phenomenological behavior of drying.The objective this scientific investigation is the developement of a
computational methodology that is able to simulate the transient profile of temperature and moisture during drying of meat product. The three-dimension simulation developed included the transport equations: mass, momentum and energy conservation. This work is organised in three steps: in the first step numerical simulation using computational fluid dinamics (CFD) were conducted to predict a couple heat and mass transfer during drying tunnel process of a calabresa sausage. The local heat and mass transfer coefficients were calculated around the calabresa sausage. The model allows calculating and predicting the temperatures and moisture content that agree with experimental data. The aim of second step, were predict the isothermal tri-dimensional air flow in the industrail forced-convection oven. The CFD model consists of the continuity, momentum and standard ê-å approach to model the turbulence flow. The performance of the CFD model was assessed by means of point measurements of the velocity with a hot-film anemometer sensor and a good agreement of the 3D flow pattern in a forced convection oven was found. Based ond the previous steps, the third step was characterized by drying of a set thirty pieces of calabresa sausage in industrial oven. The external flow and temperature fields are first numerically predicted through the comercial Ansys-CFX® package. From these distribuitions, the local distribuitions of convective heat transfer coefficients are determined, wich then used to predict local distribuitions of the convective mass transfer coefficients through the analogy between the thermal and concentration boundary layers. Also, the temperature and moisture distribuitions for different periods of time are obtained using the code developed to determine heat and mass transfer inside the moist material. The results obtained from the present analysis are comapoared with the experimental data, and a good agreement was observed. The main results demonstrated that the methodology, based on CFD techniques, was able to reproduce the phenomenological behavior of drying.
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufsc.br:123456789/92837 |
| Date | 24 October 2012 |
| Creators | Piaia, Julio Cesar Zanchet |
| Contributors | Universidade Federal de Santa Catarina, Quadri, Marintho Bastos, Bolzan, Ariovaldo |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis |
| Format | 95 f.| il., tabs., grafs. |
| Source | reponame:Repositório Institucional da UFSC, instname:Universidade Federal de Santa Catarina, instacron:UFSC |
| Rights | info:eu-repo/semantics/openAccess |
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