Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy最新文献

{"title":"Dependence of LPBF Surface Roughness on Laser Incidence Angle and Component Build Orientation","authors":"R. Subramanian, D. Rule, Onur Nazik","doi":"10.1115/gt2021-59755","DOIUrl":"https://doi.org/10.1115/gt2021-59755","url":null,"abstract":"\u0000 Laser Powder Bed Fusion (LPBF) of metallic components is unlocking new design options for high efficiency gas turbine component designs not possible by conventional manufacturing technologies. Surface roughness is a key characteristic of LPBF components that impacts heat transfer correlations and crack initiation from co-located surface defects — both are critical for gas turbine component durability and performance. However, even for a single material, there is an increasing diversity in laser machines (single vs multi-laser), layer thicknesses (∼20–80 microns) and orientations to the build plate (upskin, vertical and downskin) that result in significant variability in surface roughness. This study systematically compares the surface roughness across the above-mentioned variables to further develop a repeatable correlation of surface roughness to the angle between the substrate normal and laser incidence direction. This presented data will be discussed in detail, to show potential applicability of this process signature curve across materials, machines, and substrate orientations. Future steps to a rapid process qualification standard for surface roughness, across Siemens Energy’s global manufacturing footprint will also be discussed.","PeriodicalId":286637,"journal":{"name":"Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124608133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Performance Gain by Interstage Injection in a Four-Stage Axial Compressor","authors":"T. Doerr, S. Schuster, D. Brillert","doi":"10.1115/gt2021-58560","DOIUrl":"https://doi.org/10.1115/gt2021-58560","url":null,"abstract":"\u0000 Recently, the energy market has seen a shift towards renewable energies due to changing demands. Gas turbines are used as a transitional technology to cope with grid fluctuations. The changing conditions have increased the interest in applying Wet Compression in order to increase the power output during peak demands.\u0000 The novelty of this paper arises from the experimental results of Interstage Injection by analysing the stage and overall pressure ratios at different operating points in the four stage axial compressor “eco.MAC” (“evaporative cooling Multiphase Axial Compressor”). An innovative injection design is realized with twin jet nozzles in the trailing edge of SLM printed stator blades. A variation of water mass fraction, inlet temperature and rotational speed is performed and shows a gain in pressure ratio up to 1.5 %. Moreover, a polynomial approach is used for the dry data to compare wet and dry results at equal air mass flow rates. For the first time, a linear dependency of the pressure gain on the compressor’s gas temperature is experimentally found.\u0000 It can be concluded that Interstage Injection is an effective technology to be applied in later stages of axial compressors due to the strong influence of local gas temperatures on the evaporation rate and thus the pressure gain. Furthermore, reducing the local injection rate decreases aerodynamic losses between the liquid and gas phase. Hence, a multiple injection and reduced local injection rates should be targeted.","PeriodicalId":286637,"journal":{"name":"Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123352299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructure of IN738LC Fabricated Using Laser Powder Bed Fusion Additive Manufacturing","authors":"Nandana Menon, Tanjheel H. Mahdi, A. Basak","doi":"10.1115/gt2021-58786","DOIUrl":"https://doi.org/10.1115/gt2021-58786","url":null,"abstract":"\u0000 Nickel-base superalloys are extensively used in the production of gas turbine hot-section components as they offer exceptional creep strength and superior fatigue resistance at high temperatures. Such improved properties are due to the presence of precipitate-strengthening phases such as Ni3Ti or Ni3Al (γ′ phases) in the normally face-centered cubic (FCC) structure of the solidified nickel. Although this second phase is the main reason for the improvements in properties, the presence of such phases also results in increased processing difficulties as these alloys are prone to crack formation. In this work, specimens of IN738LC are fabricated on a Coherent Creator laser powder bed fusion (L-PBF) additive manufacturing (AM) equipment. Optical microscopy (OM), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), and X-Ray diffraction (XRD) are carried out to characterize the deposit region. Metallurgical continuity is achieved in the entire deposit region and the specimens do not show any warpage. However, the specimens show voids (e.g., pores and cracks) in the deposit region. The results show that the percentage void area decreases along the build height direction. The deposited IN738LC shows polycrystalline grains in the entire deposit region as confirmed by XRD and EBSD. The grain size also shows variations along the build direction. In summary, the results open opportunities for academic researchers and small-scale businesses in fabricating high-γ′ nickel-base superalloys on a desktop laser powder bed fusion AM equipment.","PeriodicalId":286637,"journal":{"name":"Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124039376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Associated Gas Utilization Using a Reheat Gas Turbine – Part 1: The Impact of Engine Degradation on the Optimized Power, Energy, and Revenue From Sold Electricity","authors":"M. Obhuo, D. S. Aziaka, D. Igbong, Ibirabo M. Obhuo","doi":"10.1115/gt2021-59778","DOIUrl":"https://doi.org/10.1115/gt2021-59778","url":null,"abstract":"\u0000 This study presents a methodology for optimizing the power from a fleet of engines that use associated gas as fuel. The effects of engine degradation on optimized power, energy, and electricity revenue have been evaluated.\u0000 The Cranfield University TURBOMATCH has been used to simulate a 296MW reheat gas turbine. Four scenarios were considered — clean, optimistic, medium, and pessimistic. Genetic algorithm was used in optimizing the power generated from the fleets.\u0000 In the sequence of clean, optimistic, medium, and pessimistic fleets, the optimization results show that the total optimized power values are 7324.6, 7245.1, 7164.0, and 7074.4MW respectively. In the same sequence, the total energy generated is 64.2, 63.5, 62.8, and 61.9 billion kWh. In a similar sequence still, the electricity revenue is 8.487, 8.390, 8.298, and 8.192 billion US dollars respectively. In comparison with the clean, engine degradation resulted in a 1.09%, 2.19%, and 3.42% decrease in energy for the optimistic, medium, and pessimistic degraded fleets respectively. In the same sequence as the decrease in energy, degradation resulted in a 1.15%, 2.23%, and 3.48% decrease in electricity revenue.\u0000 The methodology and results presented in this paper would serve as a guide for associated gas investors in the economic utilization of this fuel resource. This is innovative; it has not been done with the Alstom GT-26 engine.","PeriodicalId":286637,"journal":{"name":"Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129311447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Testing and Acceptance of Semi-Machined Turbine Rotor Forging Elements","authors":"S. Ingistov, D. Nagy","doi":"10.1115/gt2021-60028","DOIUrl":"https://doi.org/10.1115/gt2021-60028","url":null,"abstract":"\u0000 Turbine wheels are critical elements and the integrity of their forgings is extremely important. The procurement of wheel forgings utilized oversized outside diameters in order to provide ample amount of material from which test material was cut out. Test specimens were produced in accordance with relevant ASTM standards. Test specimens were divided into three groups; tension, impact and hardness / metallography. Tension and impact tests at sub-zero, room and elevated temperatures were conducted in presence of owner’s inspectors at an independent certified laboratory. Once all specimens passed the tests, the semi-machined forgings were released to the machining facility. Machined forgings were then sent for over-speed tests at sub-zero and elevated temperatures. Over-speed testing under sub-zero temperature was the ultimate test of the forgings. Over-speed testing of the forgings under elevated temperatures served to minimize residual tensile stresses at the bore of the wheel and convert them to beneficial compressive stresses. The above described tests of turbine Elements forging are critical when the owner selects third party producers to reverse engineer and manufacture these elements. This paper details the selection of the tests, the execution of the owner’s acceptance testing program, especially the over-speed tests, and how this helps to ensure the high integrity of critical rotating elements for a mid-size heavy industrial frame gas turbine.","PeriodicalId":286637,"journal":{"name":"Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129303273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Cradle to Gate Approach for Life-Cycle-Assessment of Blisk Manufacturing","authors":"K. Fricke, S. Gierlings, P. Ganser, Martin Seimann, T. Bergs","doi":"10.1115/GT2021-59479","DOIUrl":"https://doi.org/10.1115/GT2021-59479","url":null,"abstract":"\u0000 The aviation industry has been growing continuously over the past decades. Despite the current Covid-19 crisis, this trend is likely to resume in the near future. On an international level, initiatives like the Green Recovery Plan promoted by the European Union set the basis towards a more environmentally friendly future approach for the aero-industry. The increasing air traffic and the focus on a more sustainable industry as a whole lead to an extensive need for a more balanced assessment of a products life cycle especially on an ecological level.\u0000 Blisks (or IBRs) remain a central component of every current and very possible every future aero engine configuration. Their advantages during operation compared to conventional compressor rotors are met with a considerably complex manufacturing and production process. In the high-pressure compressor segment of an engine, the material selection is limited to Titanium alloys such as Ti6Al4V and heat-resistant Nickel-alloys such as Inconel718. The corresponding process chains consist of numerous different process steps starting with the initial raw material extraction and ending with the quality assurance (cradle to gate). Especially the central milling process requires a highly qualified process design to ensure a part of sufficient quality.\u0000 Life-Cycle-Assessments enable an investigation of a products overall environmental impact and ecological footprint throughout its distinct life-cycle. Formal LCAs are generally divided by international standards into four separate steps of analysis: the goal and scope definition, the acquisition of Life Cycle-Inventory, the Life-Cycle-Impact-Assessment and the interpretation. This content of this paper focuses on a general approach for Life-Cycle-Assessment for Blisk manufacturing.\u0000 • Firstly, the goal and scope is set by presenting three separate process chain scenarios for Blisk manufacturing, which mainly differ in terms of raw material selection and individual process selections for blade manufacturing.\u0000 • Secondly, the LCI data (Life-Cycle Inventory) acquisition is illustrated by defining all significant in- and outputs of each individual process step.\u0000 • Thirdly, the approach of a Life-Cycle-Impact-Assessment is presented by introducing the modelling approach in an LCA-software environment.\u0000 • Fourthly, an outlook and discussion on relevant impact-indicators for a subsequent interpretation of future results are conducted.","PeriodicalId":286637,"journal":{"name":"Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy","volume":"152 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127576975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tolerance-Based Optimization of Sinking EDM for Industrial Seal Slot Manufacture","authors":"T. Petersen, Markus Zeis, T. Bergs","doi":"10.1115/gt2021-59266","DOIUrl":"https://doi.org/10.1115/gt2021-59266","url":null,"abstract":"\u0000 Seal plates for turbine vanes significantly reduce gap losses and thus play a major role in increasing the efficiency of turbines. The industrial production of seal slots, which position the seal plates in the turbine vanes, is driven by the need for high productivity in combination with a reliable processing of necessary geometrical and surface integrity features. A machining technology that is able to machine hard-to-cut materials such as nickel-based alloys is electrical discharge machining. Due to its electro-thermal working principle it is able to machine materials independently from their mechanical properties even at high aspect ratios. Achievable removal and wear rates as well as the resulting surface properties strongly depend on the discharge energy. Furthermore, the discharge energy affects the working gap sizes and therefore flushing efficiencies when machining high aspect ratio cavities. This relationship is investigated taking into account various contemporary generator technologies and graphite grades from both published literature and own experimental investigations. Their effect on machining performance focusing on productivity, recast layer thickness and crack formation is quantified. Based on this data a novel empirical model for tolerance-based optimization is developed. The model is used to perform an optimization on an existing serial production and implementation has been proven successful.","PeriodicalId":286637,"journal":{"name":"Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132672837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Low-Cycle Fatigue Behavior of HAYNES 244 Alloy and Waspaloy","authors":"M. Fahrmann","doi":"10.1115/gt2021-59619","DOIUrl":"https://doi.org/10.1115/gt2021-59619","url":null,"abstract":"\u0000 HAYNES® 244® alloy was chiefly developed to address the need for high-strength, low coefficient of thermal expansion (CTE) alloys for seal rings and cases in advanced gas turbine engines. In addition to these attributes, adequate resistance to low-cycle fatigue (LCF) due to cyclic thermal and mechanical loading during service is critical for such applications. The isothermal LCF performance of commercially produced 0.5” (12.5 mm) thick, fully heat treated plate products of 244 alloy was evaluated by means of axial strain-controlled (R = −1) LCF tests covering total strain ranges up to 1.25 % (without dwells), at temperatures ranging from 800–1400°F (427–760°C). In addition, the comparative LCF performance of Waspaloy, a well-established alloy for turbine cases, was evaluated under selected, nominally identical test conditions. S-N curves were constructed and fitted by the Coffin-Manson equation, allowing the delineation of regimes controlled by the elastic and plastic response of the material. Fracture surfaces were examined in the scanning electron microscope to identify fatigue crack initiation sites and crack propagation modes. Differences between the alloys are discussed in terms of tensile strength and cyclic hardening/softening behavior. Implications for fatigue performance of these alloys under cyclic thermal loading conditions are discussed as well.","PeriodicalId":286637,"journal":{"name":"Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133360596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Design of an ORC Axial Turbine Based Expander Working As a Mechanical Driver in Gas Compressor Stations","authors":"L. Branchini, Cesar Celis, Sebastián Ruiz, R. Aguilar, A. D. Pascale, F. Melino","doi":"10.1115/gt2021-01559","DOIUrl":"https://doi.org/10.1115/gt2021-01559","url":null,"abstract":"\u0000 In this work, the feasibility of increasing the capacity of a natural gas compressor station by means of an Organic Rankine Cycle (ORC) is studied. In the proposed configuration, the ORC recovers natural gas compressor drivers’ wasted heat and converts it into mechanical energy. Thus, as innovative approach, the ORC generated mechanical power will be used to drag an additional gas compressor. A case study representative of a medium-size on-shore facility is taken as reference. The mechanical drivers’ arrangement is composed of four recuperated GTs of PGT5 R type (three units continuously operating and one used as back-up) and two smaller engines of Solar Saturn 20 type. Assuming the actual operation of the station, the addition of an ORC, as bottomer cycle, is designed to recover the exhaust heat from the three PGT5 R running units. According to the Authors’ preliminary investigations and state of the art MW-size parameters, a regenerative sub-critical ORC cycle is selected. Therminol 66 and Hexamethyldisiloxane (MM) are chosen as intermediate and working fluids, respectively. The design ORC key cycle parameters are identified: about 2700 hp (2 MW) of capacity could be added to drive a compressor. For a comprehensive investigation, ORC off-design operating range is explored too assuming one out of three topper cycle units out of service. Since a direct coupling of the ORC driver and the gas compressor is expected, thus excluding the use of gearboxes to avoid losses, an ORC axial turbine based expander is designed that accommodates variable speed operation. The referred design includes mean-line calculations and three-dimensional computational fluid dynamics (CFD) based numerical simulations at design and off design point conditions.","PeriodicalId":286637,"journal":{"name":"Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127116850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unlocking the Green Economy for Aeroderivative Gas Turbines","authors":"N. C. Corbett, Michel Houde, K. Bohan, Simon Batt","doi":"10.1115/gt2021-60264","DOIUrl":"https://doi.org/10.1115/gt2021-60264","url":null,"abstract":"\u0000 If existing gas turbine engines are to remain as the primary choice source of power for supplying short term peaking power capacity in an emergency, then they will need to be capable of directly using a alternative carbon neutral fuel supply. It is important that the fuel can be stored locally to ensure operation of the gas turbine can be provided without reliance upon supplies through distribution network infrastructure or stored hydrogen. Alternative carbon neutral fuels such as synthetic electro or biomass manufactured from hydrogen with nitrogen or CO2 to produce respectively; nitrofuel (Ammonia) or carbofuel (Methanol). Both fuels are renewable and compatible with existing carbon supply chain infrastructure as they can be similarly transported and stored as liquids with similar properties.\u0000 Digital technologies can help accelerate the uptake of carbon neutral solutions by operators by assisting them to make greener choices, from the data and information presented to them, promoting the use of their assets demonstrating their contribution and responsibilities to managing the environment. Whilst progress in adopting digital technology has been slow, it is by linking the investment to decarbonization that could then be considered as a value adder rather than a regulatory requirement.\u0000 The paper discusses the program of work to develop a bundle of digital services whilst decarbonizing aeroderivative gas turbine applications.","PeriodicalId":286637,"journal":{"name":"Volume 7: Industrial and Cogeneration; Manufacturing Materials and Metallurgy","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127258037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}