Commercial Dynamic Simulation Software Research Articles

Influence of different heating systems on thermal comfort perception: a dynamic and CFD analysis

In this paper, we investigate the influence of different heating systems on the thermal comfort indexes, Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD), for a residential apartment located in Bologna (Italy). The apartment has an area of 40 m2 and is located on the ground floor of 4 floors building. The envelop consists in horizontal perforated bricks with internal thermal insulation material and two windows. The analyses are performed employing Trnsys, a commercial dynamic simulation software and Simcenter STAR-CCM+, a multiphysics computational fluid dynamics (CFD) software. The CFD analysis regards a steady condition of a typical winter day in Bologna. Thermal comfort indexes and thermal energy demand are studied comparing two different heating generation systems existing in the considered apartment: a condensing gas boiler coupled with radiators as terminal emitters and an air-to-air heat pump. By crossing the results obtained by the dynamical approach and by the CFD simulations, a two-objective methodology where energy consumption is minimised while thermal comfort is obtained, is presented.

Rigorous dynamic simulation methodology for scenario-based safety analysis of pressure-swing distillation considering independent protections

Process engineers often assess process safety performance early in the design stage to reduce or eliminate potential hazards cost-effectively. Process simulation tools widely used in design can provide fast and precise hazard evaluation using limited design information. However, there is a knowledge gap on how to build rigorous dynamic process models and how model configurations can affect safety analysis results. This study applied commercial dynamic simulation software, Aspen Dynamics, to address these issues through rigorous dynamic simulations and safety analysis of a two-column pressure-swing distillation with top recycling. The study implements and simulates various layers of protection, including basic process controls, alarms, safety instrumented systems, and pressure relief systems, and evaluates their impact on accident prevention. The hazardous scenarios considered are overpressure and flooding in the distillation columns, and the dynamic responses to a set of deviations such as coolant and steam utility failures and undesired throughput and composition disturbances are investigated. A scenario-based safety analysis is performed to assess the dynamic safety performance and the effectiveness of protection layers. The results indicate that the presented scenario-based dynamic safety analysis methodology is essential for accurately determining dynamic column behaviors, thereby better assisting in determining process safety time and designing effective safety systems.

Quasi-Coordinates-Based Closed-Form Dynamic Modeling and Analysis for a 2R1T PKM with a Rigid–Flexible Structure

This work derives a closed-form dynamic model for a two rotational and one translational degrees-of-freedom (2R1T) parallel kinematic mechanism (PKM) with a hybrid rigid–flexible structure for force-control applications. Based on the three-prismatic-prismatic-spherical (3PPS) kinematic configuration of the 2R1T PKM and its zero-torsion motion characteristics, a symbolic formulation approach is proposed to establish closed-form kinematic models for both forward and inverse kinematics analysis. As the moving platform pose of the 2R1T 3PPS PKM can be readily determined by the three active prismatic joint variables and the three passive prismatic joint variables, these six joint variables are selected as the quasi-coordinates so as to systematically develop the closed-form dynamic model with a Lagrangian formulation, in which the stiffness and deformation of the three flexure-based passive prismatic joints are uniformly taken into consideration. Through eliminating the three passive prismatic joint variables based on the principle of virtual work and the relationships between the active and passive prismatic joint variables, a closed-form dynamic model for the 2R1T 3PPS PKM with a rigid–flexible structure is finally obtained. The correctness of the closed-form dynamic model was validated with the commercial dynamic simulation software. Utilizing the closed-form dynamic model, the effects of different flexure stiffness in driving directions on the required active joint force were investigated, which indicated that little flexure stiffness in driving directions is desired.

Agricultural tractor dynamics simulation research based on a driving simulator with real-time human-machine interaction

Vehicle dynamics simulation based on the driving simulator has great application potential. Compared with field tests, it has the advantages of low cost, high reproducibility, safety, and controllability. Compared with commercial dynamics simulation software, it can realize real-time human-machine interaction by providing a highly immersed virtual scene and operational environment. In order to verify the feasibility of agricultural tractor dynamics simulation based on the driving simulator, the dynamics model of 8 degrees of freedom (8DOF) was built using MATLAB/Simulink and Visio Studio, and the human-machine interaction environment composed of the tractor cab, data acquisition system, controller, central server and display system was constructed. Secondly, the simulation software based on the dynamics model was developed based on the virtual reality engine of Unity3D. Finally, Carsim was applied as the feasibility verification tool with similar tractor models and virtual environments. The turning road test, undulating road test, and cross-slope road test were carried out in the driving simulator and Carsim with the same simulation conditions. Yaw rate and roll angle given by both platforms above were analyzed with statistical methods and error analysis. The results showed that dynamics curves of the simulator had high shape similarity with the curves of Carsim. No significant difference was demonstrated between curves of the simulator and Carsim. There was a relative error from 6.34% to 19.63% in yaw rate data from the simulator compared with Carsim results. Likewise, the relative error for roll angle data given by the simulator ranged from 6.12% to 20.72%. The results verified the feasibility of high-accuracy dynamics simulation in the driving simulator. Our research laid the foundation for further research and application of agricultural tractor dynamics simulation based on driving simulators with real-time human-machine interaction.

Proxy modelling for multi-well simulations: enabling identification of major input variables and reduced computation time over Monte Carlo sampling

The petroleum industry uses high level dynamic simulations applied to geocellular models to guide forecasts of oil, gas and water production. Uncertainty in model choice and input variable selection is often addressed through large numbers of computationally slow Monte Carlo simulations designed around physics based models. Here, an alternate approach is proposed, which uses a relatively small amount of data and a reduced number of simulations of the high level physics model to train a fast (to evaluate) proxy or surrogate model based on a Polynomial Chaos Expansion. We give details of the theory and incorporated techniques, which significantly increase flexibility. Input variables (e.g. cell-by-cell variations in porosity and permeability) are sampled from unknown probability distributions and sensitivity analysis is based on low level proxy models. The theory is tested by developing proxy models to predict total gas production from a five-spot well configuration in the Hermitage area that taps into the Walloon Coal Measures of the Surat Basin in Queensland. Synthetic training data is simulated using commercial dynamic simulation software based on a high level physics model.

도마뱀 생체 데이터를 이용한 속보 걸음새 생성

A variety of studies on imitating the skeletal structure and the gait of legged animals have been done in order to develop walking robots which have an ability to adapt to atypical environments. In this paper, we analyzed the gait of a Bearded dragon lizard using the motion capture system, proposed a calibration scheme of the motion data and generated the trotting gait of a lizard based on the calibrated data. Also, we constructed the dynamic model based on the biometric data of a Bearded dragon lizard and applied the trotting gait of the lizard to the dynamic model. We verified the validity of the gait with the commercial dynamic simulation software.

Dynamic-Simulation Applications Support Challenging Offshore Operations

This article, written by Editorial Manager Adam Wilson, contains highlights of paper SPE 156146, ’Dynamic-Simulation Applications To Support Challenging Offshore Operations: A Kitan Oil Field Offshore East Timor Case Study,’ Ryosuke Yokote, SPE, and Vanni Donagemma, Eni Australia, and Juan Carlos Mantecon, SPE, SPT Group, prepared for the 2012 SPE Annual Technical Conference and Exhibition, San Antonio, Texas, 8-10 October. The paper has not been peer reviewed. The Kitan oil field consists of three subsea intelligent wells. The intelligent completions were modeled in detail using commercial dynamic-simulation software to establish a sound and safe operating procedure for the well cleanup and well test. The simulation results provided the petroleum engineer on the rig with key operational information, such as the time for the oil to arrive at surface and expected pressure at the downhole gauges (DHGs) and upstream of the choke manifold. This enhanced the ability of rigsite supervisors to anticipate well behavior, enabling a significant risk reduction. Introduction The Kitan oil field is approximately 200 km south of the East Timor coast and 500 km offshore of the northern coast of Australia (Fig. 1). The Kitan field development consists of three vertical producing wells, 6-in. production subsea flowlines and risers, 2-in. gas-injection lines, umbilical lines, and a floating production, storage, and offloading (FPSO) vessel. Each well has a designated flow-line and riser tied back to the FPSO vessel (Fig. 2). Fig. 3 shows the intelligent completion for the Kitan development wells. The intelligent completion was de-signed to control flow from two separate zones, upper and lower. Flow from each zone is controlled by flow-control valves (FCVs) that have eight positions (fully opened, fully closed, and six intermediate choke positions). Pressure and temperature for each zone are monitored by three DHGs. The FCVs have a fail-as-is design and stay in the last position should a communications problem be encountered. Because of the remoteness of the location, the functionality of the intelligent completion and the well performance needed to be confirmed with a minimum degree of uncertainty. To establish a sound and safe operating procedure for the well cleanup and well test, commercial dynamic simulation software was used to model the intelligent completion and selected operations. A few different well-cleanup procedures were investigated to predict cleanup time, pressure and temperature at different points of interest, and flow rates on the rig. The simulation results provided valuable information, enabling the petroleum engineer on the rig to predict flow conditions of the well during the operations. Following the successful well-cleanup and well-test campaign, the well models were validated with actual well-cleanup and -test data.

Experiences on dynamic simulation software in chemical engineering education

Commercial process simulators are increasing interest in the chemical engineer education. In this paper, the use of commercial dynamic simulation software, D-SPICE® and K-Spice®, for three different chemical engineering courses is described and discussed. The courses cover the following topics: basic chemical engineering, operability and safety analysis and process control. User experiences from both teachers and students are presented. The benefits of dynamic simulation as an additional teaching tool are discussed and summarized. The experiences confirm that commercial dynamic simulators provide realistic training and can be successfully integrated into undergraduate and graduate teaching, laboratory courses and research.

Production system analysis for Woollybutt mature oil field using dynamic simulation

This paper describes how multi-phase flow dynamic simulation techniques were applied to support and optimise the day to day production operations for the Woollybutt oil field on the North West Shelf, Australia. Eni Australia is the operator of the: Woollybutt oil project, which consists of two separate fields; Woollybutt North, which has three production wells; and Woollybutt South, which has one production well– Woollybutt–4H (WBT–4H). WBT–4H is located about 7 km from the floating production storage and offloading (FPSO) facilities and shares the production flowline with two other production wells from the Woollybutt North field. Production from WBT-4H accounts for more than 60% of the total production. For this reason, achieving steady production from this well is the highest priority for the operations. To understand the hydrodynamic behaviour and to maximise production from WBT–4H, the production system for the Woollybutt South field was modelled from WBT–4H reservoir inflow points to the FPSO using a commercial dynamic simulation software package. The model successfully matched the pressures measured at the permanent down hole gauge (PDHG) and upstream production subsea choke dynamically, using the arrival pressure at the FPSO and the measured gas lift rate at the FPSO as input data. The model was used to identify the reason for slugging , to locate where the slugging conditions were originating, as well as to investigate optimum gas lift rate and the impact of bringing other wells on production from the Woollybutt South field. Furthermore, the model was used to identify the cause of sudden severe slugging, which forced to reduce the subsea production choke opening. The simulation work concluded that an unstable gas injection at the gas lift orifice valve (GLOV) induced severe slugging. This conclusion was validated operationally in the field soon after. Results of the multi-phase flow dynamic simulation provided good understanding of the hydrodynamic behaviour in the production system and are used to make informed decisions to support and optimise the day to day production operations.

Nonlinear Dynamic Data Reconciliation via Process Simulation Software and Model Identification Tools

Existing strategies for the solution of the nonlinear dynamic data reconciliation problem use the process model as a constraint which is expressed as a differential−algebraic equation system. Modeling a process using conservation laws may require a considerable number of equations to obtain an accurate representation of the system. It is possible to model a process using commercial dynamic simulation software. However, this also requires the solution of a large number of equations interfaced to reliable optimization software in order to perform data reconciliation. This paper focuses on two new approaches for dynamic data reconciliation using model identification tools and commercial dynamic simulation software. The first one is based on an analogy to the nonlinear dynamic data reconciliation method developed by Liebman et al.1 The second approach uses time series analysis to generate a simplified model of the plant. A simplified process model is generated by a model identification method to replace the simulation software. Several techniques including parametric and nonparametric methods can be applied to identify a local input−output model from simulation results. Data reconciliation constrained by this reduced model yields a more computationally efficient algorithm.