The JT8D and JT9D engine component improvement: Performance improvement program

The NASA sponsored Engine Component Improvement - Performance Improvement Program at Pratt & Whitney Aircraft advanced the state of the art of thermal barrier coatings and ceramic seal systems, demonstrated the practicality of an advanced turbine clearance control system and an advanced fan design in the JT9D engine, and demonstrated the advantages of modern cooling, sealing, and aerodynamic designs in the high pressure turbine and compressor of the JT8D engine. Several of these improvements are already in airline service in JT8D and JT9D engines, and others will enter service soon in advanced models of these engines. In addition, the technology advances are being transferred to completely new engine configurations, the PW2037 engine and the NASA sponsored Energy Efficient Engine

JT90 thermal barrier coated vanes

The technology of plasma sprayed thermal barrier coatings applied to turbine vane platforms in modern high temperature commercial engines was advanced to the point of demonstrated feasibility for application to commercial aircraft engines. The three thermal barrier coatings refined under this program are zirconia stabilized with twenty-one percent magnesia (21% MSZ), six percent yttria (6% YSZ), and twenty percent yttria (20% YSZ). Improvement in thermal cyclic endurance by a factor of 40 times was demonstrated in rig tests. A cooling system evolved during the program which featured air impingement cooling for the vane platforms rather than film cooling. The impingement cooling system, in combination with the thermal barrier coatings, reduced platform cooling air requirements by 44% relative to the current film cooling system. Improved durability and reduced cooling air requirements were demonstrated in rig and engine endurance tests. Two engine tests were conducted, one of 1000 cycles and the other of 1500 cycles. All three coatings applied to vanes fabricated with the final cooling system configuration completed the final 1500 cycle engine endurance test. Results of this test clearly demonstrated the durability of the 6% YSZ coating which was in very good condition after the test. The 21% MSZ and 20% YSZ coatings had numerous occurrences of significant spalling in the test

Improving the Sustainability of Office Partition Manufacturing: Balancing Options for Reducing Emissions of Volatile Organic Compounds

Options are examined to improve the sustainability of office partition manufacturing by reducing volatile organic compounds (VOC) emissions. Base VOC emissions for a typical plant are estimated using a mass balance approach. Pollution prevention and sustainability measures are assessed using realistic criteria and weightings. Sustainability has been considered from an industry perspective, considering factors like economics, environmental impact, quality, health and safety. Through a case study, it is demonstrated that several advantageous options are available for reducing VOC emissions in manufacturing office furniture partitions, and thereby enhancing the sustainability of that industrial operation. The measures deemed most viable include implementing several best management practices, not painting of non-visible parts, switching gluing processes, recycling solvent and modifying attachments. The results are intended to be balanced so as to improve their acceptability and adoptability by industry. It appears that it would be advantageous for manufacturers of office panels to evaluate the feasibility of these measures and to implement the most appropriate. The results are likely extendable to other operations in the wood furniture industry, and would improve their sustainability

Pembinaan dan penilaian program rekabentuk rasuk keluli (PRRK) sebagai alat kognitif dalam pembelajaran rekabentuk struktur di kalangan pelajar diploma kejuruteraan awam KUiTTHO

Kajian awal yang telah dijalankan mendapati pelajar Kejuruteraan Awam KUiTTHO menghadapi masalah kognitif dalam pembelajaran mata pelajaran Rekabentuk Struktur khasnya dalam pemahaman konsep dan prosedur reka bentuk. Langkah pengiraan yang terlalu banyak selalunya mengelirukan pelajar sehinggakan mereka hilang minat dan tumpuan. Bagi membantu mereka, satu program telah disediakan dengan menggunakan perisian Microsoft Excel bagi tujuan menganalisis dan mereka bentuk rasuk keluli bagi meningkatkan tahap kemahiran kognitif terhadap matapelajaran tersebut. Program Rekabentuk Rasuk Keluli (PRRK) ini disediakan berdasarkan kaedah reka bentuk yang diamalkan oleh British Standard Institution, Structural Use of Steel Work In Building. Seramai dua puluh satu orang pelajar semester akhir Diploma Kejuruteraan A warn yang mengambil mata pelajaran Rekabentuk Struktur telah diminta menilai program ini. Penilaian telah dijalankan terhadap isi, sifat mesra pengguna dan kebolehlaksanaan program menggunakan kaedah skor min. Selain itu perkaitan antara pengalaman pelajar menggunakan komputer sebagai sumber pembelajaran dengan penilaian PRRK juga telah dilihat. Keputusan skor min menunjukkan isi PRKK adalah baik, bersifat mesra pengguna dan mempunyai sifat kebolehlaksanaan. Ujian korelasi Spearman pula menunjukkan bahawa tidak terdapat sebarang perkaitan yang signifikan di antara pengalaman pelajar menggunakan komputer sebagai sumber pembelajaran dengan penilaian PRRK

Phase 1 of the automated array assembly task of the low cost silicon solar array project

The state of technology readiness for the automated production of solar cells and modules is reviewed. Individual process steps and process sequences for making solar cells and modules were evaluated both technically and economically. High efficiency with a suggested cell goal of 15% was stressed. It is concluded that the technology exists to manufacture solar cells which will meet program goals

Life Cycle Based Sustainability Assessment And Decision Making For Industrial Systems

Increasing concern with the environmental impact resulted from human activities has led to a rising interest in sustainable development that will not only meet the needs of current development but also protect the natural environment without compromising the needs of future generations. This leads to the necessity of a systems approach to decision-making in which economic, environmental and social factors are integrated together to ensure the triple bottom lines of sustainability. Although current studies provide a variety of different methodologies to address sustainability assessment and decision-making, the increasing size and complexity of industrial systems results in the necessity to develop more comprehensive systems approaches to ensure the sustainable development over a long time period for industrial systems. What\u27s more, current research may conduct results based on one or only a few stages of the manufacturing process without considering all the stages of a product’s life. Therefore, the results could be bias and sometimes not feasible for the whole life-cycle. In the meanwhile, life cycle analysis (LCA) which has been widely adopted in a variety of industries does provide an effective approach to evaluate the environmental impact. The lack of life-cycle based economic and social sustainability assessment results in the difficult to conduct more comprehensive sustainability assessment. To address these challenges, three fundamental frameworks are developed in this dissertation, that is, life cycle based sustainability assessment (LCBSA) framework, life cycle based decision-making (LCBDM) framework, and fuzzy dynamic programming (FDP) based long-term multistage sustainable development framework. LCBSA can offer a profound insight of status quo of the sustainability performance over the whole life cycle. LCSA is then applied to assess the industrial system of automotive coating manufacturing process from raw material extraction, material manufacturing, product manufacturing to the recycle and disposal stage. The following LCBDM framework could then prioritize the sustainability improvement urgency and achieve comprehensive sustainable development by employing a two-phase decision-making methodology. In addition, FDP based long-term multistage sustainable development framework offers a comprehensive way to ascertain the achievement of long time sustainable development goal of complex and dynamic industrial systems by combining decision-making and sustainability assessment together

Demonstration of the feasibility of automated silicon solar cell fabrication

An analysis of estimated costs indicate that for an annual output of 4,747,000 hexagonal cells (38 mm. on a side) a total factory cost of $0.866 per cell could be achieved. For cells with 14$1.22 per watt of electrical output. A laboratory model of such a facility was operated to produce a series of demonstration runs, producing hexagonal cells, 2 x 2 cm cells and 2 x 4 cm cells

Multiscale Design And Life-Cycle Based Sustainability Assessment Of Polymer Nanocomposite Coatings

In recent years, nanocoatings with exceptionally improved and new performance properties have found numerous applications in the automotive, aerospace, ship-making, chemical, electronics, steel, construction, and many other industries. Especially the formulations providing multiple functionalities to cured paint films are believed to dominate the coatings market in the near future. It has shifted the focus of research towards building sustainable coating recipes which can deliver multiple functionalities through applied films. The challenge to this exciting area of research arrives from the insufficient knowledge about structure-property correlations of nanocoating materials and their design complexity. Experimental efforts have been successful in developing certain types of nanopaints exhibiting improved properties. However, multifunctional nanopaint design optimality is extremely difficult to address if not impossible solely through experiments. In addition to this, the environmental implications and societal risks associated with this growing field of nanotechnology raise several questions related to its sustainable development. This research focuses on the study of a multiscale sustainable nanocoating design which can have the application from novel function envisioning and idea refinement point of view, to knowledge discovery and design solution derivation, and further to performance testing in industrial applications. The nanocoating design is studied using computational simulations of nano- to macro- scale models and sustainability assessment study over the life-cycle. Computational simulations aim at integrating top-down, goals/means, inductive systems engineering and bottom-up, cause and effect, deductive systems engineering approaches for material development. The in-silico paint resin system is a water-dispersible acrylic polymer with hydrophilic nanoparticles incorporated into it. The nano-scale atomistic and micro-scale coarse-grained (CG) level simulations are performed using molecular dynamics methodology to study several structural and morphological features such as effect of polymer molecular weight, polydispersity, rheology, nanoparticle volume fraction, size, shape and chemical nature on the bulk mechanical and self-cleaning properties of the coating film. At macro-scale, a paint spray system which is used for automotive coating application is studied by using CFD-based simulation methodology to generate crucial information about the effects of nanocoating technology on environmental emissions and coating film quality. The cradle-to-grave life-cycle based sustainability assessment study address all the critical issues related to economic benefits, environmental implications and societal effects of nanocoating technology through case studies of automotive coating systems. It is accomplished by identifying crucial correlations among measurable parameters at different stages and developing sustainability indicator matrices for analysis of each stage of life-cycle. The findings from the research can have great potential to draft useful conclusions in favor of future development of coating systems with novel functionalities and improved sustainability

SimLack: simulation-based optimization and scheduling of generic powder coating lines

https://www.asim2018.de/Powder coating and paint-spray lines are often complex production plants because of many dynamical dependencies, limited buffer space and sequence dependent changeover times. We have developed a generic simulation and optimization platform that enables the engineers to design more performant and energy efficient facilities and the production planners to increase productivity through simulation-based optimization. The simulation environment builds on a generic modelling library that captures all variations of such facilities. Execuable models are generated automatically from annotated CAD layouts. As a result, the system smoothly integrates with the engineering process. Once the facility is in use, the fully specified virtual plant is used for simulation-based scheduling, employing a combination of a generic priority-based heuristic and a variant of simulated annealing. We discuss how these two aspects of the system render it an important innovation for the painting line industry and show first results from the scheduling system