This paper starts from the single tube condensation theory of shell side inferred by Nusselt , and then analyzes the coefficient of heat transfer of the shell side and the overall heat transfer coefficient of the tube bundle. Referring to the overall heat coefficient of surface condensers and the calculation means of pressure decrease, the HEI, the most exploited one in the commerce is used by combining the basic theory of condenser heat transfer based on the Delphi function language to develop a set of assistant designing software. The software can be used to evaluate the performance of condensers, calculate the sizes of tube materials, and predict the pressure of condensers when the different tube materials are used. When the units are in using, this software also can calculate the cleanliness factor and determine the suitable time to clean the condenser tubes. There are four common used tube materials to compare their performance. They are Al- Brass tubes, 70-30 Cu-Ni tubes, Sea-Cure tubes and Ti tubes. This paper use the software to analyze the performance of the heat transfer of these four different kinds of tube materials and also to calculate the sizes of tubes .And use research papers to analyze the reason of anti-corrosion of these four. In addition, the HEI method can analyze the anti-vibration ability of these four. After comparing with all the performance of the tube materials, and then choosing the best tube material to provide an example for condenser design of new electricity plants or for old electricity plants to change the tube materials.

Utilizing an experimental facility which was prepared to conduct performance tests on heat exchangers; experiments were completed in an attempt to see verifiable improvements in overall heat transfer coefficient in engine coolant with nanoparticles suspended at different weight percentages. The different fluids tested were: base ELC (Extended Life Coolant), ELC with 0.002 wt% CNT (Carbon Nanotubes), ELC with 0.02 wt% CNT, ELC with 0.02 wt% MWNT's (Multiwalled Nanotubes) and water. The volume percents range from 0.00164 volume% to 0.0164 volume% which seemed quite small, but according to Caterpillar representatives, were the best concentration. These fluids were tested at standard flowrates which this type of heat exchanger would be used in as well as a higher air flowrate and lower coolant flowrates in an attempt to gather more verifiable data. Results were obtained regarding the change in heat transfer ability of engine coolant with suspended nanoparticles. For this system under these specific conditions, there was verifiably no increase in UA as nanoparticles were added to the coolant. The benefits of adding nanoparticles to engine coolant have potential to be great, but the cost of nanoparticles and difficulty keeping them suspended may outweigh any benefits obtainable in this type of set up.

Modeling of heat transfer using Dymola. In this report a evaporator, economizer and superheater where modeled. The report describes how the models where modeled and what input was most suitable for a accurate model.

Um painel sanduíche consiste essencialmente em duas faces, podendo inclusive possuir reforços metálicos e um núcleo formado normalmente por um polímero celular. As faces deste tipo de painel podem estar unidas por um adesivo estrutural, ou por espuma rígida de poliuretano (PU) injetado diretamente sobre os substratos, quando a união ocorrerá naturalmente. A propriedade de maior relevância que o painel sanduíche deve ter para o transporte de cargas congeladas (0ºC a -30ºC) ou refrigeradas (7ºC a 1ºC) é a condutividade térmica (k). Dentro deste contexto o objetivo deste trabalho foi propor e caracterizar painéis sanduíches que possam ser utilizados em câmaras frigoríficas. Este trabalho apresenta as seguintes alternativas para compósito sanduíche: amostra 1 (PRFV/PU/PRFV); amostra 2 (AG/PU/AG); amostra 3 (Frisado/PU/PRFV); e amostra 4 (Al/PU/Al), onde PRFV é poliéster reforçado com fibra de vidro, PU é espuma rígida de poliuretano, AG é aço galvanizado, Frisado é alumínio frisado, e Al é alumínio. Estes painéis foram caracterizados quanto às propriedades físico-mecânicas, térmicas, morfológicas e custo. Foi possível concluir que o sistema (AG/PU/AG) mostrou o melhor custo versus desempenho dentre os compósitos propostos. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-05-29T19:30:53Z No. of bitstreams: 1 Dissertacao Ana Paola Sartori.pdf: 3882091 bytes, checksum: c7530ac27f11dffba880ed97ee828f31 (MD5) / Made available in DSpace on 2014-05-29T19:30:53Z (GMT). No. of bitstreams: 1 Dissertacao Ana Paola Sartori.pdf: 3882091 bytes, checksum: c7530ac27f11dffba880ed97ee828f31 (MD5) / A sandwich panel consists essentially of two face sheets and may even have metal reinforcements and a core formed, usually by a cellular polymer. The faces of this type of panel may be joined by a structural adhesive or in cases where the core is a rigid polyurethane foam injected directly on the substrates the union will occur naturally. The most relevant property of the sandwich panels for the transport of frozen (0ºC a -30ºC) or chilled (7ºC a 1ºC) cargo is thermal conductivity (k). Within this context the objective of this work is to obtain and characterize sandwich panels which can be used in refrigerated chambers. This work presents four alternatives for composite sandwich, sample 1 (PRFV/PU/PRFV), sample 2 (AG/PU/AG), sample 3 (Al Crimpy/PU/PRFV) and sample 4 (Al /PU/Al), were PRFV is a glass fibre reinforced plastics, PU is a rigid polyurethane, AG is galvanized steel, Al Crimpy is crimpy aluminum and Al is aluminum. These composites were characterized by physicalmechanical, thermal, morphologic and cost. It could be concluded that the AG/PU/AG showed the best cost versus performance.

Um painel sanduíche consiste essencialmente em duas faces, podendo inclusive possuir reforços metálicos e um núcleo formado normalmente por um polímero celular. As faces deste tipo de painel podem estar unidas por um adesivo estrutural, ou por espuma rígida de poliuretano (PU) injetado diretamente sobre os substratos, quando a união ocorrerá naturalmente. A propriedade de maior relevância que o painel sanduíche deve ter para o transporte de cargas congeladas (0ºC a -30ºC) ou refrigeradas (7ºC a 1ºC) é a condutividade térmica (k). Dentro deste contexto o objetivo deste trabalho foi propor e caracterizar painéis sanduíches que possam ser utilizados em câmaras frigoríficas. Este trabalho apresenta as seguintes alternativas para compósito sanduíche: amostra 1 (PRFV/PU/PRFV); amostra 2 (AG/PU/AG); amostra 3 (Frisado/PU/PRFV); e amostra 4 (Al/PU/Al), onde PRFV é poliéster reforçado com fibra de vidro, PU é espuma rígida de poliuretano, AG é aço galvanizado, Frisado é alumínio frisado, e Al é alumínio. Estes painéis foram caracterizados quanto às propriedades físico-mecânicas, térmicas, morfológicas e custo. Foi possível concluir que o sistema (AG/PU/AG) mostrou o melhor custo versus desempenho dentre os compósitos propostos. / A sandwich panel consists essentially of two face sheets and may even have metal reinforcements and a core formed, usually by a cellular polymer. The faces of this type of panel may be joined by a structural adhesive or in cases where the core is a rigid polyurethane foam injected directly on the substrates the union will occur naturally. The most relevant property of the sandwich panels for the transport of frozen (0ºC a -30ºC) or chilled (7ºC a 1ºC) cargo is thermal conductivity (k). Within this context the objective of this work is to obtain and characterize sandwich panels which can be used in refrigerated chambers. This work presents four alternatives for composite sandwich, sample 1 (PRFV/PU/PRFV), sample 2 (AG/PU/AG), sample 3 (Al Crimpy/PU/PRFV) and sample 4 (Al /PU/Al), were PRFV is a glass fibre reinforced plastics, PU is a rigid polyurethane, AG is galvanized steel, Al Crimpy is crimpy aluminum and Al is aluminum. These composites were characterized by physicalmechanical, thermal, morphologic and cost. It could be concluded that the AG/PU/AG showed the best cost versus performance.

The aim of this diploma thesis is to get acquainted with modern technological elements currently used in shell-and-tube heat exchanger in the shell-side and tube-side, thermal-hydraulic calculation of selected elements and comparison of thermal-hydraulic properties with classically used competing technological elements. The work deals mainly with EM baffle in the tube-side and tube inserts like the twisted tape type (and its modifications) and coiled wire in the tube-side. The theoretical part is focused on acquaintance with classical technological elements in shell-and-tube heat exchanger and with basic thermal-hydraulic calculations, practical part then on acquaintance with modern elements and thermal-hydraulic calculation of selected elements. These calculations are then compared with the results of the thermo-hydraulic calculation of similar elements.