Design methodology for wing trailing edge device mechanisms

Over the last few decades the design of high lift devices has become a very important part of the total aircraft design process. Reviews of the design process are performed on a regular basis, with the intent to improve and optimize the design process. This thesis describes a new and innovative methodology for the design and evaluation of mechanisms for Trailing Edge High-Lift devices. The initial research reviewed existing High-Lift device design methodologies and current flap systems used on existing commercial transport aircraft. This revealed the need for a design methodology that could improve the design process of High-Lift devices, moving away from the conventional "trial and error" design approach, and cover a wider range of design attributes. This new methodology includes the use of the innovative design tool called SYNAMEC. This is a state-of-the-art engineering design tool for the synthesis and optimizations of aeronautical mechanisms. The new multidisciplinary design methodology also looks into issues not usually associated with the initial stages of the design process, such as Maintainability, Reliability, Weight and Cost. The availability of the SYNAMEC design tool and its ability to perform Synthesis and Optimization of mechanisms led to it being used as an important module in the development of the new design methodology. The SYNAMEC tool allows designers to assess more mechanisms in a given time than the traditional design methodologies. A validation of the new methodology was performed and showed that creditable results were achieved. A case study was performed on the ATRA - Advance Transport Regional Aircraft, a Cranfield University design project, to apply the design methodology and select from within a group of viable solutions the most suitable type of mechanism for the Variable Camber Wing concept initially defined for the aircraft. The results show that the most appropriate mechanism type for the ATRA Variable Camber Wing is the Link /Track Mechanism. It also demonstrated how a wide range of design attributes can now be considered at a much earlier stage of the design.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Modeling and Control of Co-Surge in Bi-Turbo Engines.

Abstract: Using a bi-turbocharged configuration makes for better utilization of the exhaust energy and a faster torque response in V-type engines. A special surge phenomenon that should be avoided in bi-turbocharged engines is co-surge, which is when the two interconnected compressors alternately go into flow reversals. If co-surge should occur, the control system must be able to quell the oscillations with as little disturbance in torque as possible. This paper presents a model of a bi-turbocharged engine based on a Mean Value Engine Model that includes a MoreGreizer compressor model for surge. The model is validated against measured data showing that it captures the frequency and amplitude of the co-surge oscillation. The effect of momentum conservation in the pipes is investigated by adding this feature to the control volumes before and after the compressor. This gives a slightly better mass flow shape with the drawback of increased simulation time, due to more states and a higher frequency content in the model. A sensitivity analysis is performed to investigate which model parameters have most influence on the co-surge behavior. It is shown that the largest influence comes from the turbocharger inertia, the volumes after the compressor and the "zero mass flow pressure ratio" during flow reversal in the compressor. The model is used to investigate principles for control strategies to detect and quell co-surge. The detection algorithm is evaluated on measured data

Promotion of a new product in the Kurzeme region.

SIA “Eltete Rīga” ir nepieciešams virzīt jaunu produktu tirgū, lai paplašinātu sortimentu un piedāvāt klientiem jaunu un inovatīvu risinājumu dažādām dzīves situācijām. Piedāvājot šo materiālu, uzņēmums atrisina dārzkopībā sastopamu problēmu. Piemēram, puves un nevēlamu sakņu aizsardzību, kā arī nezāļu kontrolēšanu augiem un stādiem. Tika izvirzīts kvalifikācijas darba mērķis: Jauna produkta virzīšana uzņēmumā SIA “Eltete Rīga”. Mērķa sasniegšanai tika izvirzīti konkrēti uzdevumi: 1.Apkopot literatūras un informācijas avotus par jaunu produktu, tā ieviešanu un virzīšanas procesu uzņēmumā. 2.Analizēt virzīšanas pasākumu specifiskās iezīmes šajā produkta dzīves cikla posmā. 3.Izveidot aptauju un apkopot datus. 4.Izstrādāt jauna produkta virzīšanas plānu. 5.Apkopot secinājumus. 6.Izvirzīt priekšlikumus. Tika izmantota: monogrāfiskā jeb aprakstošā metode, lai apkopotu informāciju, pamatotu ar literatūras apskatu; aptaujas metode, lai noskaidrotu pircēju pamudinājumu iegādāties jaunus produktus un kādas īpašības uzrunā klientus iegādāties jaunus produktus; grafiskā metode, atspoguļojot pētījumā izvirzīto jautājumu atbildes. Darbs strukturēts nodaļās un to apakšnodaļās, balstoties uz izvirzītajiem uzdevumiem un mērķi. Darba apjoms ir 69 lpp, kurās ir 13 attēli un 3 pielikumi, kuri ietilpst 9 lapaspusēs. Darbā tika izmantoti 23 literatūras un informācijas avoti. Atslēgas vārdi: SIA “Eltete Rīga”, jauns produkts, produkta virzīšana, Kurzemes reģions.SIA “Eltete Rīga” needs to promote new products in the market in order to expand the assortment and offer customers a new and innovative solution for various life situations. By offering this material, the company solves a problem in horticulture. For example, protection of rot and unwanted roots, as well as weed control for plants and seedlings. The aim of the qualification work was set: A new product promotion plan in the company SIA “Eltete Rīga”. In order to achieve the goal, specific tasks were set: 1.To compile sources of literature and information about a new product, its introduction and promotion process in the company. 2.Analyze the specific features of promotion measures at this stage of the product life cycle. 3.Create a survey and collect data. 4.Develop a new product promotion plan. 5.Summarize the conclusions. 6.Make proposals. The following were used: monographic or descriptive method to gather information based on a literature review; a survey method to find out customers' incentives to buy new products and what characteristics appeal to customers to buy new products; graphical method, reflecting the answers to the questions raised in the study. The work is structured in chapters and their subchapters, based on the set tasks and goals. The volume of the work is 69 pages, which contains 13 images and 3 appendices, which are included in 9 pages. 23 literature and information sources were used in the work. Keywords: SIA “Eltete Rīga”, new product, product promotion, Kurzeme region

Co-Surge Detection and Control for Bi-Turbo Engines with Experimental Evaluation

A V-type engine with a bi-turbocharger configuration utilizes the exhaust energy well which gives a fast torque response. An unwanted instability, called co-surge, can occur in such engines where the two interconnected compressors alternately go into flow reversals. If co-surge occurs, the control system must quell the oscillations with as little disturbance in engine torque as possible. A model of a bi-turbocharged engine is presented, combining a mean value engine model and a Moore-Greizer compressor model for surge. The model is validated against measurements on a vehicle dynamometer, showing that it captures the frequency and amplitude of the co-surge oscillation. The model is used to develop detection and control strategies for co-surge that rapidly returns the turbo to a stable operating point. Both simulations and experimental evaluation on the vehicle show that the developed strategies are successful in rapidly detecting and quelling co-surge. The selection of actuators is also studied. With no or small pressure drops over the throttle, it is necessary to use the bypass valves. However, for operating conditions with moderate and high pressure drops over the throttle, it is shown that it is sufficient to only open the throttle. This has the advantage, compared to opening the bypass valves, that it reduces the drop in boost pressure and thus reduces the drop in engine torque

Effects of Pulsating Flow on Mass Flow Balance and Surge Margin in Parallel Turbocharged Engines

The paper extends a mean value model of a parallel turbocharged internal combustion engine with a crank angle resolved cylinder model. The result is a 0D engine model that includes the pulsating flow from the intake and exhaust valves. The model captures variations in turbo speed and pressure, and therefore variations in the compressor operating point, during an engine cycle. The model is used to study the effect of the pulsating flow on mass flow balance and surge margin in parallel turbocharged engines, where two compressors are connected to a common intake manifold. This configuration is harder to control compared to single turbocharged systems, since the compressors interact and can work against each other, resulting in co-surge. Even with equal average compressor speed and flow, the engine pulsations introduce an oscillation in the turbo speeds and mass flow over the engine cycle. This simulation study use the developed model to investigates how the engine pulsations effect the in cycle variation in compressor operating point and the sensitivity to co-surge. It also shows how a short circuit pipe between the two exhaust manifolds could increase surge margin at the expense of less available turbine energy

Modeling and Control of Co-Surge in Bi-Turbo Engines

Using a bi-turbocharged configuration makes for better utilization of the exhaust energy and a faster torque response in V-type engines. A special surge phenomenon that should be avoided in bi-turbocharged engines is co-surge, which is when the two interconnected compressors alternately go into flow reversals. If co-surge should occur, the control system must be able to quell the oscillations with as little disturbance in torque as possible. This paper presents a model of a bi-turbocharged engine based on a Mean Value Engine Model that includes a More-Greizer compressor model for surge. The model is validated against measured data showing that it captures the frequency and amplitude of the co-surge oscillation. The effect of momentum conservation in the pipes is investigated by adding this feature to the control volumes before and after the compressor. This gives a slightly better mass flow shape with the drawback of increased simulation time, due to more states and a higher frequency content in the model. A sensitivity analysis is performed to investigate which model parameters have most influence on the co-surge behavior. It is shown that the largest influence comes from the turbocharger inertia, the volumes after the compressor and the ``zero mass flow pressure ratio'' during flow reversal in the compressor. The model is used to investigate principles for control strategies to detect and quell co-surge. The detection algorithm is evaluated on measured data

Effects of Pulsating Flow on Mass Flow Balance and Surge Margin in Parallel Turbocharged Engines

Abstract The paper extends a mean value model of a parallel turbocharged internal combustion engine with a crank angle resolved cylinder model. The result is a 0D engine model that includes the pulsating flow from the intake and exhaust valves. The model captures variations in turbo speed and pressure, and therefore variations in the compressor operating point, during an engine cycle. The model is used to study the effect of the pulsating flow on mass flow balance and surge margin in parallel turbocharged engines, where two compressors are connected to a common intake manifold. This configuration is harder to control compared to single turbocharged systems, since the compressors interact and can work against each other, resulting in co-surge. Even with equal average compressor speed and flow, the engine pulsations introduce an oscillation in the turbo speeds and mass flow over the engine cycle. This simulation study use the developed model to investigates how the engine pulsations affect the in cycle variation in compressor operating point and the sensitivity to co-surge. It also shows how a short circuit pipe between the two exhaust manifolds could increase surge margin at the expense of less available turbine energy