Compound cycle engine for helicopter application

The Compound Cycle Engine (CCE) is a highly turbocharged, power compounded, ultra-high power density, light-weight diesel engine. The turbomachinery is similar to a moderate pressure ratio, free power turbine engine and the diesel core is high speed and a low compression ratio. This engine is considered a potential candidate for future military light helicopter applications. This executive summary presents cycle thermodynamic (SFC) and engine weight analyses performed to establish general engine operating parameters and configuration. An extensive performance and weight analysis based on a typical two hour helicopter (+30 minute reserve) mission determined final conceptual engine design. With this mission, CCE performance was compared to that of a T-800 class gas turbine engine. The CCE had a 31% lower-fuel consumption and resulted in a 16% reduction in engine plus fuel and fuel tank weight. Design SFC of the CCE is 0.33 lb-HP-HR and installed wet weight is 0.43 lbs/HP. The major technology development areas required for the CCE are identified and briefly discussed

Au carrefour des entretiens: Etude croisée de dix TPE

Description of a sample of ten very small firms in the context of a research for thesis. Place of the new technologies of information and communication and typology of the networks which these companies join.Descriptif d'un échantillon de dix très petites entreprises dans le contexte d'une recherche de thèse. Place des nouvelles technologies d'information et de communication et typologie des réseaux dans lesquels ces entreprises s'inscrivent

Light curves for bump Cepheids computed with a dynamically zoned pulsation code

The dynamically zoned pulsation code developed by Castor, Davis, and Davison was used to recalculate the Goddard model and to calculate three other Cepheid models with the same period (9.8 days). This family of models shows how the bumps and other features of the light and velocity curves change as the mass is varied at constant period. The use of a code that is capable of producing reliable light curves demonstrates that the light and velocity curves for 9.8 day Cepheid models with standard homogeneous compositions do not show bumps like those that are observed unless the mass is significantly lower than the 'evolutionary mass.' The light and velocity curves for the Goddard model presented here are similar to those computed independently by Fischel, Sparks, and Karp. They should be useful as standards for future investigators

Arquitectura do grao e do esquecemento: muíños hidráulicos nas parroquias de Aguasantas, Buxán e Ermedelo, Concello de Rois, A Coruña

[Resumo] Cando a día de hoxe falase de arquitectura ou temas relacionados, un dos termos que mais se escoitan na conversa son os de arquitectura sostible, arquitectura bioclimática, rehabilitación, arquitectura ecolóxica, eco-arquitectura, arquitectura verde ou arquitectura ambientalmente consciente ………….., sen darnos conta que por diante dos nosos ollos, eses termos, xa eran empregados polos nosos vellos de maneira racional e necesaria para o uso case que cotián dos labores básicos de subsistencia. O muíño é un claro exemplo de aproveitamento dos recursos naturais para configurar una arquitectura adaptada á contorna e que poida responder ás necesidades das persoas aproveitando unicamente o que a natureza dános gratuitamente.Os muíños son claro exemplo de como a arquitectura adaptada á contorna pode responder dun xeito sostible ás necesidades do home sen poñer en risco os recursos naturais ou facer un uso irresponsable dos mesmos. Quero dicir que os valores naturais e culturais dos nosos ríos son as caras dun mesmo patrimonio e ambas partes estamos obrigados a conservalas e transmitilas a outras xeracións pois se trata dun patrimonio herdado. Pero o problema xorde cando se sabe que no Concello obxecto de parte deste traballo existen restos de máis de 150 muíños repartidos polas 13 parroquias do Concello nunha extensión aproximada de 93 km2, segundo se recolle no libro Clodio González Pérez “O concello de Rois: historia, economía e arte, catálogo arqueolóxico, artístico e monumental” editado polo Concello de Rois no ano 1990. O obxectivo deste traballo pretende levar a cabo a localización dos muíños das parroquias de Aguasantas, Buxán e Ermedelo, debuxar e indicar o estado de algúns muíños que son testemuño da relación dos nosos pobos co río e, polo tanto, deberían ser un patrimonio suxeito a protección, cousa que, por desgraza a día de hoxe, non o son, porque a gran maioría pertencen ao mundo do abandono e o esquecemento, co fin de servir de base para unha futura e mais completa catalogación de todas as parroquias que configuran o Concello de Rois. Non existe unha valoración do patrimonio edificado nin do paisaxístico o que pode chegar a supoñer a súa desaparición. O descoñecemento é o peor inimigo que temos. Necesitariamos inventariar todos os nosos ríos a efectos de coñecemento e protección do seu patrimonio edificado e natural. Nalgunhas administracións realizáronse inventarios onde pode coñecerse o valor de cada un deses edificios e asígnaselles algún tipo de protección. Non é o caso do Concello que se esta a estudar. Pero o labor de inventariar ou catalogar entendese ardua e lenta, e xa houbo suficientes perdas irreparables para estar esperando aos inventarios xerais. Entendemos que mentres tanto é imprescindible tomar medidas cautelares e urxentes que eviten derribas indiscriminadas. O traballo pretende ser un grao de area na montaña, motivado en gran parte, pola falta de disposición cronolóxica e climática, polo que o traballo desenvolveuse nunha pequena parte a modo de simboloxía do Concello de Rois, como a continuación se expón.[Abstract] When today’s we talked about architecture or related subjects, one of the terms that more listen in the chatter they are of :sustainable architecture, bioclimátic architecture, rehabilitation, ecological architecture, echo-architecture, green architecture or environmentally conscious architecture .............., without realize that in front of our eyes, those terms, were already used by our old people in a rational way and necessary for the use almost that daily of the basic works of subsistence. The mill is one clear example of the use of the natural resources to configure an architecture adapted to the environment and that it can answer to the needs for the people only using the natural resources. The mills are clear example how the architecture can adapted to the environment and can answer in a sustainable way to the needs of the people without putting in risk the natural resources or to do an irresponsible use of them. I want to say that the natural and cultural values of our rivers are the faces of a same patrimony and both parts we are obliged to preserving them and to transmit them to the others generations, because it is an inherited patrimony. But the problem arises when it is known that in the council on behalf of this work there are remains more than 150 mills spread in the 13 parishes of the Council in an approximate 93 km2, collected in the book Clodio González Pérez "The council of Rois: history, economy and art, archaeological, artistic and monumental catalog" edited by the Council of Rois in 1990. The object of this work intends to carry out the location of the mills on the parishes of Aguasantas, Buxán and Ermedelo, draw and indicate the state of some mills that they are testimony of the relation of our people with the river, therefore, they should be a protection patrimony, thing that it don’t have from now, because the great majority are abandoned and forgotten, in order to act as base for a future and complete cataloguing of all the parishes that configure the Council of Rois. There is not assessment of the building patrimony either of the landscape and may disappear. The ignorance is the worst enemy that we have. We would need an inventory of all our rivers to effects of knowledge and protection of his built and natural patrimony. In some administrations inventories were carried out where the value of each of those buildings can be known and some type of protection is assigned to them. These is not the case in this Council. But the work of inventorying or cataloguing understood hard and slow, and there were already enough irreparable losses to be waiting for the general inventories. We understand that meanwhile taking is gauged circumspection measured and urgent that they avoid you demolish indiscriminately. The work intends to be one in one billion, caused for the lack of chronological and climatic arrangement, therefore the work was developed in a symbol of the Council of Rois, like as next it is exposed.Traballo fin de grao (UDC.EUAT). Arquitectura técnica. Curso 2013/201

Compound cycle engine for helicopter application

The compound cycle engine (CCE) is a highly turbocharged, power-compounded, ultra-high-power-density, lightweight diesel engine. The turbomachinery is similar to a moderate-pressure-ratio, free-power-turbine gas turbine engine and the diesel core is high speed and a low compression ratio. This engine is considered a potential candidate for future military helicopter applications. Cycle thermodynamic specific fuel consumption (SFC) and engine weight analyses performed to establish general engine operating parameters and configurations are presented. An extensive performance and weight analysis based on a typical 2-hour helicopter (+30 minute reserve) mission determined final conceptual engine design. With this mission, CCE performance was compared to that of a contemporary gas turbine engine. The CCE had a 31 percent lower-fuel consumption and resulted in a 16 percent reduction in engine plus fuel and fuel tank weight. Design SFC of the CCE is 0.33 lb/hp-hr and installed wet weight is 0.43 lb/hp. The major technology development areas required for the CCE are identified and briefly discussed