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Now showing items 81-90 of 155
Aufsatz
Process and utility systems integration and optimisation for ultra-low energy milk powder production
(2017-04-26)
This study applies a Total Site Heat Integration approach in conjunction with a detailed process and utility model, to develop an innovative ultra-low energy milk powder plant design. The basis for the analysis is a state-of-the-art modern milk powder plant that requires 5265 MJ/tp of fuel and 210.5 kWh/tp (58.5 MJe/tp) of electricity. The model of the modern milk powder plant was validated against industrial data and changes to process and/or utility systems are targeted and implemented into the model to understand ...
Aufsatz
Automatic Time Series Segmentation as the Basis for Unsupervised, Non-Intrusive Load Monitoring of Machine Tools
(2019)
Detailed energy monitoring and benchmarking at the individual component level is necessary to increase energy efficiency in complex production systems. Non-intrusive load monitoring (NILM) provides an economical solution for operational state detection and load disaggregation without the need for large-scale use of fine-grained energy meters. Existing supervised NILM approaches require detailed training data including control information about individual devices. Unsupervised approaches, on the other hand, often ...
Aufsatz
Total Site Utility Systems Optimisation for Milk Powder Production
(2016)
This study applies the Total Site Heat Integration method, in conjunction with a detailed process and utility model, to investigate three methods to increase the energy efficiency of the utility supply system for milk powder production. Sequentially explored opportunities are: (1) increasing boiler efficiency through condensing economisers, (2) waste heat recovery from the chiller unit, and (3) Combined Heat and Power (CHP) for electricity production. The basis for the analysis is the anticipated future milk powder ...
Aufsatz
Numerical Two-Scale Simulations of Damage Evolution at Refractory Materials
(2014-02-25)
Fracture and damage processes on micro- and mesoscale are combined with macroscale simulations applying numerical multiscale approaches. Cracks and grain boundaries are reproduced in cell models that take account of transand intercrystalline crack growth. The global, in general thermomechanical boundary value problem is considered within a continuum mechanics framework. Two approaches are presented combining the scales. Simple processes on the smaller level are described in analytical models including the damage ...
Konferenzveröffentlichung
Verbesserung der Produktqualität durch eine frühe Anforderungsvalidierung mithilfe der virtuellen Realität
(Otto-von-Guericke-Universität, Fakultät für Maschinenbau, 2015)
If features meet customer requirements to 100%, one speaks about quality. In the context of the requirement identification various methods are used to generate the conscious customer requirements. Hidden (unconscious) customer requirements are not taken into account. From collected customer requirements, however, the later features can be derived. Therefore, in the developed product it often comes to a deviation from the characteristics required by the customer. Any deviation results in a lower product quality. The ...
Aufsatz
Sensor Concept Based on Piezoelectric PVDF Films for the Structural Health Monitoring of Fatigue Crack Growth
(2011)
A new sensor concept for monitoring fatigue crack growth in technical structures is presented. It allows the in-situ determination of the position of the crack tip as well as the fracture mechanical quantities. The required data are obtained from a piezoelectric polymer film, which is attached to the surface of the monitored structure. The stress intensity factors and the crack tip position are calculated from electrical potentials obtained from a sensor array by solving the non-linear inverse problem.
Aufsatz
Crack path predictions and experiments in plane structures considering anisotropic properties and material interfaces
(2015-09-28)
In many engineering applications special requirements are directed to a material's fracture behavior and the prediction of crack paths. Especially if the material exhibits anisotropic elastic properties or fracture toughnesses, e.g. in textured or composite materials, the simulation of crack paths is challenging. Here, the
application of path independent interaction integrals (I-integrals), J-, L- and M-integrals is beneficial for an accurate crack tip loading analysis.
Numerical tools for the calculation of loading ...
Konferenzveröffentlichung
Concept for selecting and integrating traceability systems in the continuous improvement process of SMEs
(2019)
Industry 4.0 is characterized by digitization, globalized markets and a growing demand for individualized products. Therefore, the success of manufacturing companies heavily relies on innovative and customer driven products. However, the industrializing phase of such products is often characterized by the occurring of errors originating in a lack of experience. If errors are not detected prior to delivery, costs will increase considerably (e.g. expensive product recalls). Traceability systems can clearly identify the ...
Konferenzveröffentlichung
Quality Improvement In Manual Assembly By Software-Based Evaluation Of Human Misconduct
(European Safety and Reliability Association, 2019)
For reaching a level of high quality, production processes must be carried out both, economically and reliably. Despite automation and digitalization, manual assembly operations still constitute a key element for creating efficient production processes. However, in practice, creating robust and efficient manual assembly processes often fails because the occurrence of human errors cannot be quantified prospectively. Therefore, a corresponding procedure has been developed at the institutes of the authors. The module-based ...
Aufsatz
Microscale-Motivated Continuum Damage Simulations of Brittle Ceramics under Thermomechanical Loading
(2016-05-02)
Two approaches towards modeling damage in a brittle material caused by thermomechanical loading are presented.
Bothrelyonmicrocrack growth, in the first case in ahomogeneousmatrix, in the second one at grain boundaries.Two-scale simulations e.g. of thermal shocks applied to single-phase or layered structures are performed in connection with the finite element method. Damage and crack patterns are predicted just as quantities like residual strength or critical temperature jumps.