Blar i NTNU Open på forfatter "Skogestad, Sigurd"

Changing between Active Constraint Regions for Optimal Operation: Classical Advanced Control versus Model Predictive Control
ReyesLúa, Adriana; Zotica, Cristina Florina; Das, Tamal; Krishnamoorthy, Dinesh; Skogestad, Sigurd (Journal article; Peer reviewed, 2018)Control structures must be properly designed and implemented to maintain optimality. The two options for the supervisory control layer are Advanced Control Structures (ACS) and Model Predictive Control (MPC). To systematically ... 
Composition Estimation in DividingWall Columns Using Temperature Measurements
Ghadrdan, Maryam; Halvorsen, Ivar j.; Skogestad, Sigurd (Conference object; Lecture, 2011)In this work, we propose a method to estimate the product compositions in a distillation column section based on a combination of a number of temperature measurements from different locations in ... 
Control and operation of dividingwall columns with vapor split manipulation
Dwivedi, Deeptanshu (Doctoral Theses at NTNU, 15038181; 2013:20, Doctoral thesis, 2013)Thermally coupled distillation arrangements with dividingwall implemen tation provide significant energy and capital savings compared to energy intensive conventional distillation arrangements. In this thesis, the focus ... 
Control of Fuel Cells
Zenith, Federico (Doktoravhandlinger ved NTNU, 15038181; 2007:65, Doctoral thesis, 2007)This thesis deals with control of fuel cells, focusing on hightemperature protonexchangemembrane fuel cells. Fuel cells are devices that convert the chemical energy of hydrogen, methanol or other chemical compounds ... 
Control of Steadystate Gradient of an Ammonia Reactor using Transient Measurements
Bonnowitz, Harro; Straus, Julian; Krishnamoorthy, Dinesh; Jahanshahi, Esmaeil; Skogestad, Sigurd (Journal article; Peer reviewed, 2018)This paper presents the application of a steadystate realtime optimization strategy using transient measurements to an ammonia synthesis reactor case. We apply a new method for estimating the steadystate gradient of the ... 
Control structure design for a CO2refrigeration system with heat recovery
Andreasen, Glenn; Larsen, Lars F.S.; Stoustrup, Jakob; Skogestad, Sigurd (Journal article; Peer reviewed, 2019)In this work, we analyze a generic supercritical CO2refrigeration system with parallel compression, based on systems used for supermarket use. In order to maximize energy efficiency, this system has a “heatrecovery” ... 
Control Structure Design for Optimal Oparation of 4Product Thermally Coupled Columns
Dwivedi, Deeptanshu; Halvorsen, Ivar j.; Skogestad, Sigurd (Lecture, 2011)Control and operation of energy efficient complex distillation arrangements like Kaibel and Petlyuk columns can be challenging. This paper discusses the control structure design for stabilizing ... 
Control Structure Design for Two Distillation Columns in Sequence
Marvik, Tor Anders (Master thesis, 2014)Even for simple distillation systems with only two columns, the control problem can be significant. This project provides an initial outline of a systematic procedure for finding the optimal control structure, through ... 
Controllability Analysis of Ammonia Synthesis Loops
Gullberg, Rebecca Maria Brigitte (Master thesis, 2018)Present ammonia synthesis loops normally operate under stationary conditions. Generally, ammonia synthesis loops can be slow to ramp up and down due to manual mode operation. Furthermore, load disturbances are not rejected ... 
Datadriven Scenario Selection for Multistage Robust Model Predictive Control
Krishnamoorthy, Dinesh; Thombre, Mandar; Skogestad, Sigurd; Jäschke, Johannes (Journal article; Peer reviewed, 2018)A main assumption in many works considering multistage model predictive control (MPC) is that discrete realizations of the uncertainty are chosen apriori and that the scenario tree is given. In this work, we focus on ... 
Design and simulation of dividing wall column for ternary heterogeneous distillation
Le, Quang Khoa (Master thesis, 2014)Heterogeneous azeotropic distillation is routinely used in chemical industry to separate close boiling point mixtures and azeotropes, which are not easily separated in a normal distillation process. Dividing wall column ... 
Designing packed multipartition wall dividing wall columns
Dejanovic, I.; Matijasevic, L.; Halvorsen, Ivar J.; Skogestad, Sigurd; Kaibel, B.; Jansen, H.; Olujic, Z. (Lecture, 2011) 
Dividing wall columns for natural gas liquefaction plants
Halvorsen, Ivar Johan; Dejanovic, Igor; Olujic, Zarko; Skogestad, Sigurd (Journal article; Peer reviewed, 2018)In order to meet current carbon dioxide emissions reduction challenges, natural gas processing and refining industries have to find the ways to minimize energy requirements of distillation operations. Building on foundations ... 
Dynamic Extremum Seeking Control Using ARX model
Ryu, Jeongrim (Master thesis, 2018)In the design of the dynamic ESC, a wave perturbation is decided to be not a sinusoidal wave but a pseudorandom binary sequence(PRBS) wave. The reason behind this is that diverse frequencies in the PRBS wave make the ARX ... 
Dynamic modeling and optimalization of the cheese making procedure
Kjellstrøm, Tomas Tungen (Master thesis, 2017)This thesis has successfully derived an dynamic model based on analytic solutions for production of semihard cheeses on the basis of raw milk from the cattle breed Norwegian red. The main emphasis has been to create a ... 
Dynamic Simulation of Heat Exchanger with Multicomponent Phase Change
Zotica, Cristina Florina (Master thesis, 2017)A dynamic model for a heat exchanger with multicomponent phase change, part of reliquefaction cycle of natural gas, is developed. The finite control volume method is used to spatially discretize the heat exchange intro a ... 
Economic Plantwide Control for a Methanol Plant using Commercial Process Simulation Software
Reyes Lua, Adriana (Master thesis, 2014)It is desired to make the Economic Plantwide Control design procedure proposed by Skogestad (2000, 2004, 2012) available for engineers without deep knowledge of process control or optimization. The integration of the use ... 
Energy efficient distillation
Skogestad, Sigurd; Halvorsen, Ivar Johan (Journal article; Peer reviewed, 2011)Distillation is responsible for a significant amount of the energy consumption of the world’s process industry and also in the natural gas processing. There is a significant energy saving potential that can be obtained by ... 
Feedback RealTime Optimization Strategy Using a Novel Steadystate Gradient Estimate and Transient Measurements
Krishnamoorthy, Dinesh; Jahanshahi, Esmaeil; Skogestad, Sigurd (Journal article; Peer reviewed, 2019)This paper presents a new feedback realtime optimization (RTO) strategy for steadystate optimization that directly uses transient measurements. The proposed RTO scheme is based on controlling the estimated steadystate ... 
Finding Selfoptimizing Control Variables Using Process Data
Simonsen, Rannei Solbak (Master thesis, 2014)In this project we have studied a newly developed way to find selfoptimizing variables. The method studied in this thesis uses data measurements, y, to fit a quadratic cost function. By using parameters found in the cost ...