DEVELOPMENT OF OFF-DESIGN TURBOCHARGER MODELLING COMBINED WITH 1-D ENGINE MODEL

The present work aims to carry out an off-design turbocharger modellingpowered by exhaust gases from a Wärtsilä 20V34SG engine. First of all, 1-D engine model was already developed in GT-Power software whileconsidering a thermodynamic turbocharger modelling with constantisentropic efficiencies. Secondly, by using the results from 1-D enginemodel, the off-design turbocharger modelling is calibrated separately inEES software, taking into account compressible assumption, trianglevelocities and geometric dimensions. The case study is derived from a R&Dproject (ANEEL PD-06483-0318/2018) that targets to cool and dehumidifythe intake air at compressor’s upstream through a cooling coil, therebyallowing engine’s operation at reduced knocking conditions. The brakemean effective pressure (BMEP) is varied in the range of 20 to 23.45 bar,corresponding to brake power from 8.7 to 10.2 MW, respectively. With theoff-design turbocharger modelling it is possible to analyze its operationalbehavior under higher BMEP, hence, allowing to predict some importantparameters. The results showed that the turbocharger is operating within themanufacturer’s limit for BMEP of 23.45 bar, presenting total-to-staticisentropic efficiencies of 0.81 and 0.784 for compressor and turbine,respectively, rotational speed around 28135 RPM, pressure ratio atcompressor of 4.567 and maintaining control on waste-gate valve

PERFORMANCE ASSESSMENT OF A LARGE INTERNAL COMBUSTION ENGINE DUE TO INLET AIR COOLING AND DEHUMIDIFICATION: GT-POWER SOFTWARE SIMULATION

Large internal combustion engines (ICEs) performance is limited by knocking phenomenon due to harsh ambient conditions such as hot temperature and excessive humidity. The performance of these engines can be enhanced by cooling and dehumidifying the inlet air on turbocharger upstream under safe operation conditions through a cooling coil heat exchanger, hence, increasing the power output as well as reducing the brake specific fuel consumption and pollutant specific emissions. Analysis have been performed in the GT-POWER software through a 1-D thermodynamic modelling of the Wärtsilä W20V34SG engine, making it possible to verify the influence of cooled and dehumidified ambient air, considering a temperature range from 9.5°C (282.7 K) to 15.5°C (288.7 K), while keeping 1 bar for pressure and relative humidity of 100%. Furthermore, the brake mean effective pressure (BMEP) has been set from 20 to 23.45 bar with a step of 1.15 bar. Such simulations are aimed to find the maximum air temperature at the cooling coil outlet in which the average of maximum cylinder pressures does not exceed the safety limit pressure of 186 bar while maintaining control on the wastegate valve. As a result, it was possible to evaluate that the maximum temperature to be chosen, under the conditions already mentioned, should be lower than 13.8°C (287 K)

Desenvolvimento e mortalidade de espécies florestais nativas em sistemas silvipastoril.

Sistema Silvipastoril (SSP) é a combinação de árvores, pastagem e gado numa mesma área simultaneamente e manejados de forma integrada, com o objetivo de incrementar a produtividade por unidade de área. Os SSPs geralmente são criados implantando-se árvores exóticas como o eucalipto. No entanto, o uso de espécies nativas pode vir a ser interessante pelo valor da madeira e pela provisão de recursos para a fauna. A finalidade desse experimento foi avaliar o crescimento e a mortalidade de espécies florestais de ocorrência local. A área experimental ocupa oito hectares, em uma zona de transição de cerrado e de Mata Atlântica em São Carlos. Foram plantadas sete espécies florestais nativas da região: Angico Branco (Anadenanthera colubrina), Canafistula (Peltophorum dubium), Capixingui (Croton floribundus), Mutambo (Guazuma ulmijolia), lpê-felpudo (Zeyheria tuberculosa), Jequitibá-branco( Cariniana estrellensis)e Pau-jacaré( Piptadenia gonoacantha). As árvores foram dispostas em sete faixas, cada qual com três linhas paralelas, contendo em média 214 árvores, totalizando 4.500 árvores. As duas linhas periféricas foram formadas com árvores alternadas de capixingui e mutambo, já as linhas centrais foram compostas pelas outras espéciesd, istribuídas aleatoriamente.A s árvores foram avaliadas semestralmente tendo seu desenvolvimento e mortalidade monitorados por medidas de altura e diâmetro. O capixingui e o mutambo apresentaram indice de mortalidade aos 16 meses de 7,71% e 10,39%, respectivamente Pau-jacaréi, Ipê-felpudo e jequitibá-branco apresentaram pior sobrevivência: 37%, 49% e 49%, respectivamente. Ao término das avaliações, em maio/2009, foi possível identificar que o mutambo e o capixingui foram às árvores com maior crescimento em altura dentre as espécies a valiadas, a tingindo, em média 212 cm e 216 cm, respectivamente. Entre as espécies plantadas na linha central, houve melhor desenvolvimento da canafistula, que atingiu 132 cm e do pau-jacaré, com 158 cm. Ambas são leguminosas fixadoras de nitrogênio e tem uma grande importância para a fertilidade do solo. A utilização de espécies adaptadas às condições ecológicas locais é fundamental para a obtenção de taxas de sobrevivência e de desenvolvimentos desejáveis. Nas condições deste estudo, canafistula, capixingui, mutambo e angico-branco apresentaram bons resultados. A utilização de ipê-felpudo e de jequitibá branco implicará maiores cuidados, já que ambas apresentaram baixo desempenho (crescimentoe sobrevivência) no período estudado

Effects of metoclopramide-induced hyperprolactinemia on the prolactin receptor of murine endometrium

Objective: To evaluate the effects of metoclopramide-induced hyperprolactinemia, on the prolactin receptor of murine endometrium. Design: Experimental study using the RNA extraction to detect tissue prolactin recepter isoforms by reverse-transcriptase polymerase chain reaction (RT-PCR). Setting: University-based laboratory. Animal(s): Seventy-two female swiss albino mice (Mus musculus), approximately 100 days old, were divided into six 12-animal groups: (Cl) nonoophorectomized mice given vehicle; (GII) nonoophorectomized mice treated with metoclopramide; (Gill) oophorectomized mice treated with metoclopramide; (GIV)oophorectomized mice treated with metoclopramide and 17 beta-estradiol; (GV) oophorectomized mice treated with metoclopramide and micronized progesterone; (GVI) oophorectomized mice treated with metoclopramide and a solution of 17 beta-estradiol and micronized progesterone. Intervention(s): Drugs were administered for 50 days. Following euthanasia, the middle portions of the uterine horns were removed, sectioned, and immediately frozen for RT-PCR procedures. Blood was collected for the dosage of prolactin and serum estrogen and progesterone using radioimmune assay. Main Outcome Measure(s): Identification of uterine prolactin receptor isoforms: Result(s): The PRL receptor and its isoform L were identified only in GI (control group) and GII (metoclopramide), the two groups with nonoophorectomized animals. The amount of PRL receptor mRNA and that of its isoform L from GII were the largest. No other isoforms of the prolactin receptor were identified in any of the groups. Conclusion(s): Our results suggest that replacement of estrogen and progestin may not increase the mRNA of endometrial PRL receptor in metoclopromide-induced hyperprolactinemia in rats after castration. (Fertil Steril (R) 2010;93:1643-9. (C)2010 by American Society for Reproductive Medicine.