Cost Estimation of Simulation Models for the Effectiveness Estimation of Simulation-Based Acquisition

Author(s):  
Hae Young Lee ◽  
Hyung-Jong Kim
2014 ◽  
Vol 6 ◽  
pp. 217584 ◽  
Author(s):  
J. Schilp ◽  
C. Seidel ◽  
H. Krauss ◽  
J. Weirather

Process monitoring and modelling can contribute to fostering the industrial relevance of additive manufacturing. Process related temperature gradients and thermal inhomogeneities cause residual stresses, and distortions and influence the microstructure. Variations in wall thickness can cause heat accumulations. These occur predominantly in filigree part areas and can be detected by utilizing off-axis thermographic monitoring during the manufacturing process. In addition, numerical simulation models on the scale of whole parts can enable an analysis of temperature fields upstream to the build process. In a microscale domain, modelling of several exposed single hatches allows temperature investigations at a high spatial and temporal resolution. Within this paper, FEM-based micro- and macroscale modelling approaches as well as an experimental setup for thermographic monitoring are introduced. By discussing and comparing experimental data with simulation results in terms of temperature distributions both the potential of numerical approaches and the complexity of determining suitable computation time efficient process models are demonstrated. This paper contributes to the vision of adjusting the transient temperature field during manufacturing in order to improve the resulting part's quality by simulation based process design upstream to the build process and the inline process monitoring.


2019 ◽  
pp. 98-131
Author(s):  
Johannes Lenhard

This chapter shows that—and how—simulation models are epistemically opaque. Nevertheless, it is argued, simulation models can provide a means to control dynamics. Researchers can employ a series of iterated (experimental) runs of the model and can learn to orient themselves within the model—even if the dynamics of the simulation remain (at least partly) opaque. Admittedly, such an acquaintance with the model falls short of the high epistemic standards usually ascribed to mathematical models. This lower standard is still sufficient, however, when the aim is controlled intervention in technological contexts. On the other hand, opacity has to be accepted if the option for control is to remain in any way open. This chapter closes by discussing whether epistemic opacity restricts simulation-based science to a pragmatic—“weak”—version of scientific understanding.


Author(s):  
Haibo Chen ◽  
Torgeir Moan ◽  
Sverre Haver ◽  
Kjell Larsen

Tandem offloading safety between FPSO and shuttle tanker is under concern. A few collisions between the two vessels have happened in the North Sea in recent years. In these incidents, excessive relative motions (termed as surging and yawing in this paper) between FPSO and tanker are identified as “failure prone situations” which have contributed to the initiation of most collision incidents. To quantitatively assess the probability of surging and yawing events, and more importantly, to effectively reduce their occurrence in tandem offloading operation, we present a simulation-based approach in this paper, which is carried out by a state-of-the-art time-domain simulation code SIMO. The SIMO simulation models are setup and calibrated for a typical North Sea purpose-built FPSO and a DP shuttle tanker. This 2-vessel system motion in tandem offloading is simulated. The simulated relative distance and relative heading between FPSO and tanker are analyzed by fitting their extreme values into statistical models. This gives out probabilities of surging and yawing events. Sensitivity studies are performed to analyze contributions from various technical and operational factors. Measures to minimize the occurrence of surging and yawing from design and operational point of view are proposed.


Author(s):  
Zhimin Xi ◽  
Hao Pan ◽  
Ren-Jye Yang

Reliability analysis based on the simulation model could be wrong if the simulation model were not validated. Various model bias correction approaches have been developed to improve the model credibility by adding the identified model bias to the baseline simulation model. However, little research has been conducted for simulation models with dynamic system responses. This paper presents such a framework for model bias correction of dynamic system responses for reliability analysis by addressing three technical components including: i) a validation metric for dynamic system responses, ii) an effective approach for dynamic model bias calibration and approximation, and iii) reliability analysis considering the dynamic model bias. Two case studies including a thermal problem and a corroded beam problem are employed to demonstrate the proposed approaches for simulation-based reliability analysis.


Author(s):  
Wolfgang Fimml ◽  
Christian Fuchs ◽  
Thomas Jauk ◽  
Andreas Wimmer

The characterization of diesel sprays for the simulation-based optimization of injection strategies and combustion chamber geometries is of particular importance to reach future targets concerning performance, fuel consumption and emissions. The prediction quality of this simulation process depends largely upon the adequate calibration of the spray models used. This paper aims to present the experimental setup of a spray box, the applied optical visualization techniques and the results. Furthermore, it will show the adjustment and the validation of the simulation models based on the experimental analysis.


Author(s):  
Tero Eskola ◽  
Heikki Handroos

A Hardware-in-the-loop (HIL) simulation based method for designing and testing of fluid power driven machines has recently been studied in [1], [2] and [3]. In those papers the method has successfully been tested for driving physical prototypes with simulation models of various hydraulic circuits. Although the results of the tested method have appeared to be reasonable the critical boundary conditions of the system has not yet been studied. In this paper a simple hydraulic system is modeled and used for driving the simulator. The simulated system is then built from real components and measured. The measured and simulated results are compared. One of the main goals of this paper is to find answer to the following question: What is the maximum bandwidth that can be put out from the simulator with sufficient accuracy. The answer demonstrates the applicability of the developed HIL-simulator. Also different sizes of time steps are studied.


2016 ◽  
Author(s):  
Hae Young Lee ◽  
So Jin Lee ◽  
Hyung-Jong Kim ◽  
SeungHyun Byun

2018 ◽  
Vol 18 (2) ◽  
pp. 41-69 ◽  
Author(s):  
Juan Camilo Paz ◽  
David Rozenboim ◽  
Álvaro Cuadros ◽  
Sandra Cano ◽  
John Escobar

This paper tackles the problem of scheduling construction projects considering the influence of delay risks. In the actual body of knowledge, several methods have been proposed to handle this problem, starting from the Project Evaluation and Review Technique to advanced simulation models. However, this investigation proposes a novel integration of one methodology with some approaches already existing in the literature related to Monte Carlo Simulation scheduling techniques as seen from the perspective of a practitioner. The research began with a literature review of both schedule risks and Monte Carlo based scheduling models for construction projects. Based on this, the methodology was designed with the constant participation of experts in the construction industry. As result of this, a comprehensive and practical methodology was constructed. Therefore, a new mathematical structure for the simulation model within the methodology was formulated in which a new concept for each risk defined as “potential impact” was used. Moreover, the simulation model is based on the judgment of experts and methods of the known literature such as the explicit model of the occurrence probability of the risks and the activity-risk factor matrix. Then, to validate the tool, the proposed methodology was applied using the information of an already constructed construction project of a public university of Colombia. The obtained results were a confidence-based forecast of the end date of the project and a quantitative importance measure of the modelled risks. These results were compared against the real history of the project since it was found an excellent performance of the proposed methodology. To sum up, the research process described above supports the validity of the proposed methodology.


2003 ◽  
Vol 126 (3) ◽  
pp. 235-242 ◽  
Author(s):  
Haibo Chen ◽  
Torgeir Moan ◽  
Sverre Haver ◽  
Kjell Larsen

Excessive relative motions between Floating Production Storage Offloading Unit (FPSO), and tanker, which are termed as excessive surging and yawing events, are identified as the “failure prone situation” in tandem offloading. These events have contributed to the initiation of tanker drive-off in most collision incidents that happened in the North Sea in recent years. To estimate and reduce the probability of excessive surging and yawing events in tandem offloading, a simulation-based approach, which is based on a state-of-the-art time-domain simulation code SIMO, is presented in this paper. A typical North Sea FPSO and a DP shuttle tanker simulation models are setup in SIMO and calibrated by full-scale measurements. The simulated relative distance and relative heading between FPSO and tanker are analyzed by fitting their extreme values into statistical models which give out probabilities of excessive surging and yawing events. Sensitivity studies are performed to pinpoint contributions from various technical and operational factors. Measures to minimize the occurrence of excessive surging and yawing events are identified in design and operational perspectives.


2020 ◽  
Vol 5 (3-4) ◽  
pp. 187-197
Author(s):  
Philipp Rosenberger ◽  
Martin Friedrich Holder ◽  
Nicodemo Cianciaruso ◽  
Philip Aust ◽  
Jonas Franz Tamm-Morschel ◽  
...  

Abstract Validating safety is an unsolved challenge before autonomous driving on public roads is possible. Since only the use of simulation-based test procedures can lead to an economically viable solution for safety validation, computationally efficient simulation models with validated fidelity are demanded. A central part of the overall simulation tool chain is the simulation of the perception components. In this work, a sequential modular approach for simulation of active perception sensor systems is presented on the example of lidar. It enables the required level of fidelity of synthetic object list data for safety validation using beforehand simulated point clouds. The elaborated framework around the sequential modules provides standardized interfaces packaging for co-simulation such as Open Simulation Interface (OSI) and Functional Mockup Interface (FMI), while providing a new level of modularity, testability, interchangeability, and distributability. The fidelity of the sequential approach is demonstrated on an everyday scenario at an intersection that is performed in reality at first and reproduced in simulation afterwards. The synthetic point cloud is generated by a sensor model with high fidelity and processed by a tracking model afterwards, which, therefore, outputs bounding boxes and trajectories that are close to reality.


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