scholarly journals Development of a New Low-Cost Tandem Variable Geometry Turbocharging Concept for Turbocharger Applications

Author(s):  
Rodrigo R. Erdmenger ◽  
Katya Menter ◽  
Rogier Giepman ◽  
Cathal Clancy ◽  
Aneesh Vadvadgi ◽  
...  

The air handling system for large diesel/gas engines such as those used on locomotive, marine, and power generation applications require turbochargers with a high reliability and with turbomachinery capable to adjust to different operating conditions and transient requirements. The usage of variable geometry turbocharging (VGT) provides flexibility to the air handling system but adds complexity, cost and reduces the reliability of the turbocharger in exchange for improved engine performance and transient response. For this reason, it was desirable to explore designs that could provide the variability required by the air handling system, without the efficiency penalty of a conventional waste gate and with as little added complexity as possible. The current work describes a new low-cost variable geometry turbine design to address these requirements. The new tandem nozzle concept proposed is applicable to both axial and radial turbines and has been designed using conventional one-dimensional models and two- three-dimensional computational fluid dynamics (CFD) methods. The concept has furthermore been validated experimentally on two different test rigs. In order to avoid the long lead times of procuring castings, the nozzle for the axial turbine was manufactured using new additive manufacturing techniques. Both the axial turbine and the radial turbine designs showed that the concept is capable to achieve a mass flow variability of more than 15% and provide a robust and cost-effective alternative to conventional VGT designs by significantly reducing the number of moveable parts.

Author(s):  
Rodrigo R. Erdmenger ◽  
Katya Menter ◽  
Rogier Giepman ◽  
Cathal Clancy ◽  
Aneesh Vadvadgi ◽  
...  

The air handling system for large diesel/gas engines such as those used on locomotive, marine, and power generation applications require turbochargers with a high reliability and with turbomachinery capable to adjust to different operating conditions and transient requirements. The usage of variable geometry turbocharging (VGT) provides flexibility to the air handling system but adds complexity, cost and reduces the reliability of the turbocharger in exchange for improved engine performance and transient response. For this reason, it was desirable to explore designs that could provide the variability required by the air handling system, without the efficiency penalty of a conventional waste gate and with as little added complexity as possible. The current work describes a new low-cost variable geometry turbine design to address these requirements. The new tandem nozzle concept proposed is applicable to both axial and radial turbines, and has been designed using conventional 1D models and 2D/3D CFD methods. The concept has furthermore been validated experimentally on two different test rigs. In order to avoid the long lead times of procuring castings, the nozzle for the axial turbine was manufactured using new additive manufacturing techniques. Both the axial turbine and the radial turbine designs showed that the concept is capable to achieve a mass flow variability of more than 15% and provide a robust and cost-effective alternative to conventional VGT designs by significantly reducing the number of moveable parts.


2018 ◽  
Vol 52 (25) ◽  
pp. 3429-3444 ◽  
Author(s):  
Ezequiel Buenrostro ◽  
Daniel Whisler

Three-dimensional fiber-reinforced foam cores may have improved mechanical properties under specific strain rates and fiber volumes. But its performance as a core in a composite sandwich structure has not been fully investigated. This study explored different manufacturing techniques for the three-dimensional fiber-reinforced foam core using existing literature as a guideline to provide a proof of concept for a low-cost and easily repeatable method comprised of readily available materials. The mechanical properties of the fiber-reinforced foam were determined using a three-point bend test and compared to unreinforced polyurethane foam. The foam was then used in a sandwich panel and subjected to dynamic loading by means of a gas gun (103 s−1). High-strain impact tests validated previously published studies by showing, qualitatively and quantitatively, an 18–20% reduction in the maximum force experienced by the fiber-reinforced core and its ability to dissipate the impact force in the foam core sandwich panel. The results show potential for this cost-effective manufacturing method to produce an improved composite foam core sandwich panel for applications where high-velocity impacts are probable. This has the potential to reduce manufacturing and operating costs while improving performance.


Author(s):  
H. X. Liang ◽  
Q. W. Wang ◽  
L. Q. Luo ◽  
Z. P. Feng

Three-dimensional numerical simulation was conducted to investigate the flow field and heat transfer performance of the Cross-Wavy Primary Surface (CWPS) recuperators for microturbines. Using high-effective compact recuperators to achieve high thermal efficiency is one of the key techniques in the development of microturbine in recent years. Recuperators need to have minimum volume and weight, high reliability and durability. Most important of all, they need to have high thermal-effectiveness and low pressure-losses so that the gas turbine system can achieve high thermal performances. These requirements have attracted some research efforts in designing and implementing low-cost and compact recuperators for gas turbine engines recently. One of the promising techniques to achieve this goal is the so-called primary surface channels with small hydraulic dimensions. In this paper, we conducted a three-dimensional numerical study of flow and heat transfer for the Cross-Wavy Primary Surface (CWPS) channels with two different geometries. In the CWPS configurations the secondary flow is created by means of curved and interrupted surfaces, which may disturb the thermal boundary layers and thus improve the thermal performances of the channels. To facilitate comparison, we chose the identical hydraulic diameters for the above four CWPS channels. Since our experiments on real recuperators showed that the Reynolds number ranges from 150 to 500 under the operating conditions, we implemented all the simulations under laminar flow situations. By analyzing the correlations of Nusselt numbers and friction factors vs. Reynolds numbers of the four CWPS channels, we found that the CWPS channels have superior and comprehensive thermal performance with high compactness, i.e., high heat transfer area to volume ratio, indicating excellent commercialized application in the compact recuperators.


Author(s):  
Nicholas Anton ◽  
Magnus Genrup ◽  
Carl Fredriksson ◽  
Per-Inge Larsson ◽  
Anders Christiansen-Erlandsson

In the process of evaluating a parallel twin-turbine pulse-turbocharged concept, the results considering the turbine operation clearly pointed towards an axial type of turbine. The radial turbine design first analyzed was seen to suffer from sub-optimum values of flow coefficient, stage loading and blade-speed-ratio. Modifying the radial turbine by both assessing the influence of “trim” and inlet tip diameter all concluded that this type of turbine is limited for the concept. Mainly, the turbine stage was experiencing high values of flow coefficient, requiring a more high flowing type of turbine. Therefore, an axial turbine stage could be feasible as this type of turbine can handle significantly higher flow rates very efficiently. Also, the design spectrum is broader as the shape of the turbine blades is not restricted by a radially fibred geometry as in the radial turbine case. In this paper, a single stage axial turbine design is presented. As most turbocharger concepts for automotive and heavy-duty applications are dominated by radial turbines, the axial turbine is an interesting option to be evaluated for pulse-charged concepts. Values of crank-angle-resolved turbine and flow parameters from engine simulations are used as input to the design and subsequent analysis. The data provides a valuable insight into the fluctuating turbine operating conditions and is a necessity for matching a pulse-turbocharged system. Starting on a 1D-basis, the design process is followed through, resulting in a fully defined 3D-geometry. The 3D-design is evaluated both with respect to FEA and CFD as to confirm high performance and durability. Turbine maps were used as input to the engine simulation in order to assess this design with respect to “on-engine” conditions and to engine performance. The axial design shows clear advantages with regards to turbine parameters, efficiency and tip speed levels compared to a reference radial design. Improvement in turbine efficiency enhanced the engine performance significantly. The study concludes that the proposed single stage axial turbine stage design is viable for a pulse-turbocharged six-cylinder heavy-duty engine. Taking into account both turbine performance and durability aspects, validation in engine simulations, a highly efficient engine with a practical and realizable turbocharger concept resulted.


2010 ◽  
Vol 2010 (1) ◽  
pp. 000548-000553
Author(s):  
Zhaozhi Li ◽  
Brian J. Lewis ◽  
Paul N. Houston ◽  
Daniel F. Baldwin ◽  
Eugene A. Stout ◽  
...  

Three Dimensional (3D) Packaging has become an industry obsession as the market demand continues to grow toward higher packaging densities and smaller form factor. In the meanwhile, the 3D die-to-wafer (D2W) packaging structure is gaining popularity due to its high manufacturing throughput and low cost per package. In this paper, the development of the assembly process for a 3D die-to-wafer packaging technology, that leverages the wafer level assembly technique and flip chip process, is introduced. Research efforts were focused on the high-density flip chip wafer level assembly techniques, as well as the challenges, innovations and solutions associated with this type of 3D packaging technology. Processing challenges and innovations addressed include flip chip fluxing methods for very fine-pitch and small bump sizes; wafer level flip chip assembly program creation and yield improvements; and set up of the Pb-free reflow profile for the assembled wafer. 100% yield was achieved on the test vehicle wafer that has totally 1,876 flip chip dies assembled on it. This work has demonstrated that the flip chip 3D die-to-wafer packaging architecture can be processed with robust yield and high manufacturing throughput, and thus to be a cost effective, rapid time to market alternative to emerging 3D wafer level integration methodologies.


Author(s):  
Riaz A. Mufti ◽  
Martin Priest

Bench testing can provide rapid and cost effective information for developing new lubricants. But there is general agreement that the only satisfactory means of evaluating the behaviour of engine oil is by actual use in engine. Also for detailed analysis of the tribological interaction it is important to analyse the engine performance at the component level. With the help of advance data acquisition system and sensor technology, experimental measurement of friction losses at the component level have been measured at realistic engine operating conditions, using the technique explained in Part 1. This paper describes the outcome of the experimental results at a range of engine operating conditions using mainly SAE 0W20 lubricant and some results from a friction-modified SAE 5W30 lubricant. The results clearly show considerable changes in the percentage contribution of power loss between low and high lubricant temperatures. The change in mode of lubricating regime from boundary to fluid film lubrication can be seen at the component level with increase in engine speed and decrease in lubricant temperature. This system can be used as a powerful tool for screening engine oils, analysing component design, validating friction models and studying the effect of different additives on the performance of each component under realistic operating conditions.


Buildings ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 187
Author(s):  
Efstathios Adamopoulos ◽  
Monica Volinia ◽  
Mario Girotto ◽  
Fulvio Rinaudo

Thermal infrared imaging is fundamental to architectural heritage non-destructive diagnostics. However, thermal sensors’ low spatial resolution allows capturing only very localized phenomena. At the same time, thermal images are commonly collected with independence of geometry, meaning that no measurements can be performed on them. Occasionally, these issues have been solved with various approaches integrating multi-sensor instrumentation, resulting in high costs and computational times. The presented work aims at tackling these problems by proposing a workflow for cost-effective three-dimensional thermographic modeling using a thermal camera and a consumer-grade RGB camera. The discussed approach exploits the RGB spectrum images captured with the optical sensor of the thermal camera and image-based multi-view stereo techniques to reconstruct architectural features’ geometry. The thermal and optical sensors are calibrated employing custom-made low-cost targets. Subsequently, the necessary geometric transformations between undistorted thermal infrared and optical images are calculated to replace them in the photogrammetric scene and map the models with thermal texture. The method’s metric accuracy is evaluated by conducting comparisons with different sensors and the efficiency by assessing how the results can assist the better interpretation of the present thermal phenomena. The conducted application demonstrates the metric and radiometric performance of the proposed approach and the straightforward implementability for thermographic surveys, as well as its usefulness for cost-effective historical building assessments.


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Jian Huang ◽  
Yin’an Ming ◽  
Ying Du ◽  
Yingru Wang ◽  
Ci’en Wang

This study presents the electrochemical degradation of methylene blue (MB) wastewater in a synthetic solution using three-dimensional particle electrodes. The novel particle electrodes were fabricated in this work using the lithium modified rectorite (Li-REC). The adsorption property of the fabricated particle electrodes was studied in a series of experiments. The optimum electrochemical operating conditions of plate distance, cell voltage, and concentration of electrolyte were 2 cm, 9 V, and 0.06 mol L−1, respectively. It was also found that microwave irradiation can effectively improve the adsorption property and electrical property of the fabricated electrodes. In addition, the scanning electron microscope (SEM) of the fabricated electrodes was investigated. The experimental results revealed the order of adsorption property and electrical property of the fabricated electrodes. So, fabricated electrodes are not only of low cost and mass produced, but also efficient to achieve decolorization of MB solution.


Author(s):  
Ioannis Goulos ◽  
Panagiotis Giannakakis ◽  
Vassilios Pachidis ◽  
Pericles Pilidis

This paper presents an integrated approach, targeting the comprehensive assessment of combined helicopter engine designs within designated operations. The developed methodology comprises a series of individual modeling theories, each applicable to a different aspect of helicopter flight dynamics and performance. These relate to rotor blade modal analysis, three-dimensional flight path definition, flight dynamics trim solution, aeroelasticity, and engine performance. The individual mathematical models are elaborately integrated within a numerical procedure, solving for the total mission fuel consumption. The overall simulation framework is applied to the performance analysis of the Aérospatiale SA330 helicopter within two generic, twin-engine medium helicopter missions. An extensive comparison with flight test data on main rotor trim controls, power requirements, and unsteady blade structural loads is presented. It is shown that, for the typical range of operating conditions encountered by modern twin-engine medium civil helicopters, the effect of operational altitude on fuel consumption is predominantly influenced by the corresponding effects induced on the engine rather than on airframe rotor performance. The implications associated with the implicit coupling between aircraft and engine performance are discussed in the context of mission analysis. The potential to comprehensively evaluate integrated helicopter engine systems within complete three-dimensional operations using modeling fidelity designated for main rotor design applications is demonstrated. The proposed method essentially constitutes an enabler in terms of focusing the rotorcraft design process on designated operation types rather than on specific sets of flight conditions.


Author(s):  
Ioannis Goulos ◽  
Panos Giannakakis ◽  
Vassilios Pachidis ◽  
Pericles Pilidis

This paper presents an integrated approach, targeting the comprehensive assessment of combined helicopter–engine designs, within designated operations. The developed methodology comprises a series of individual modeling theories, each applicable to a different aspect of helicopter flight dynamics and performance. These relate to rotor blade modal analysis, three-dimensional flight path definition, flight dynamics trim solution, aeroelasticity and engine performance. The individual mathematical models are elaborately integrated within a numerical procedure, solving for the total mission fuel consumption. The overall simulation framework is applied to the performance analysis of the Aérospatiale SA330 helicopter within two generic, twin-engine medium helicopter missions. An extensive comparison with flight test data on main rotor trim controls, power requirements and unsteady blade structural loads is presented. It is shown that, for the typical range of operating conditions encountered by modern twin-engine medium civil helicopters, the effect of operational altitude on fuel consumption is predominantly influenced by the corresponding effects induced on the engine, rather than on airframe–rotor performance. The implications associated with the implicit coupling between aircraft and engine performance, are discussed in the context of mission analysis. The potential to comprehensively evaluate integrated helicopter–engine systems within complete three-dimensional operations, using modeling fidelity designated for main rotor design applications, is demonstrated. The proposed method essentially constitutes an enabler in terms of focusing the rotorcraft design process on designated operation types, rather than on specific sets of flight conditions.


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