s widagdo - Academia.edu (original) (raw)

Papers by s widagdo

Research paper thumbnail of Retroreflective Articles and Devices Having Viscoelastic Lightguide

Research paper thumbnail of Method of making composite material

Research paper thumbnail of Incandescent Light Bulb:  Product Design and Innovation

Industrial & Engineering Chemistry Research, 2006

In this brief article, a strategy is introduced for meshing the technical advances with the fulfi... more In this brief article, a strategy is introduced for meshing the technical advances with the fulfillment of customer needs during the development and design of new products. The concept of an innovation map is developed to connect material, process, and product technologies to the value proposition of the new products. By retracing the advances in developing incandescent light bulbs, the interplay between technical discovery and its commercialization into new products is shown. Although the design of the incandescent light bulb is presented in hindsight, this interplay is the key to the design of new products; however, unfortunately, in new product design, there are many alternatives to explore that may not be fruitful.

Research paper thumbnail of Douglas, J. M., Conceptual Design of Chemical Processes, McGraw-Hill, 1988

Research paper thumbnail of Perspectives on chemical product and process design

Computers & Chemical Engineering, 2009

In this article, new perspectives and strategies of chemical product design are provided. Beginni... more In this article, new perspectives and strategies of chemical product design are provided. Beginning with the innovation map (Widagdo, S., Incandescent light bulb: Product design and innovation, Ind. Eng. Chem. Res., 45 (25), 8231-8233 (2006)) that links the critical technological advances necessary to meet customer needs, aspects of the Stage-Gate TM product-development process (SGPDP) are considered with emphasis on the concept, feasibility, and development stages. A focus is placed on the design of basic chemical products (e.g., commodity and specialty chemicals, pharmaceuticals, polymeric materials), industrial chemical products (e.g., films, fibers, paper, glass substrates, pastes, creams), and configured-consumer chemical products (e.g., light bulbs, hemodialysis devices, labs-on-a-chip). Perspectives on the role of process design in the context of product design are presented.

Research paper thumbnail of Nonlinear analysis in process design

AIChE Journal, 1991

As steady-state and dynamic simulators with optimal controllers have evolved, tools for nonlinear... more As steady-state and dynamic simulators with optimal controllers have evolved, tools for nonlinear analysis have been developed by reactor and thermophysical property specialists. Designers lag behind in developing and utilizing these tools, as many design strategies assume idealized behavior even though processes contain an increasing number of nonlinear elements. This article examines the sources of the nonlinear elements, often associated with physical and chemical interactions, in designs and their control systems. Promising methods for nonlinear analysis are revie wed. In each design activity, involving simulation, economic optimization, projections of controllability and operability, emphasis is on the sources of nonlinearities and solution methods. These are examined for the equality constraints and nonlinear programs in phase and chemical equilibria, in reactors and separators, and in the simulation and optimization of flowsheets. Also examined are the impact of nonlinear predictive control in screening designs and methods to insure operability, in the face of uncertainties.

Research paper thumbnail of Journal review. Azeotropic distillation

AIChE Journal, 1996

Recent and ongoing research in the distillation of nonideal mixtures is reviewed focus-ing on adv... more Recent and ongoing research in the distillation of nonideal mixtures is reviewed focus-ing on advances in the methodologies for the synthesis, design, analysis and control of separation sequences involvinghomogeneous and heterogeneous azeotropic towers. Maps of residue curves ...

Research paper thumbnail of Bifurcation analysis in heterogeneous azeotropic distillation

AIChE Journal, 1989

Parameterization with respect to the aqueous reflux ratio has been carried out for the steady-sta... more Parameterization with respect to the aqueous reflux ratio has been carried out for the steady-state analysis of a tower to dehydrate secbutanol using disecondary butyl ether as the entrainer. With an equilibrium-stage model, singularities are observed as the second liquid phase is introduced on the trays and regions of steady-state multiplicity are demonstrated. Furthermore, a critical aqueous reflux ratio, in the vicinity of which two liquid phases are introduced on most of the trays, varies only slightly with the number of trays in the tower. The model predicts that the product purities and recoveries remain high using one-third of the trays in the industrial SBA-II tower. Bifurcation analysis for a single stage does not explain these observations, and the effect of recycle is suspected.

Research paper thumbnail of Dynamic analysis of heterogeneous azeotropic distillation

AIChE Journal, 1992

A model and algorithm are presented for the separation of mixtures where the phase distribution o... more A model and algorithm are presented for the separation of mixtures where the phase distribution on the trays is extremely uncertain, as it occurs when the mixtures have two partially-miscible binary pairs and a minimum-boiling ternary azeotrope. Included are an algorithm for the consistent initialization of index-I differential/ algebraic equations, a novel algorithm for branch switching when the phase distribution changes at a real bifurcation point, and a reliable algorithm for phase stability analysis. Open-loop responses are presented for the dehydration of secbutanol with disecbutylether in single-stage, I2-tray, and 33-tray separators. These simulation results for the 33-tray tower are in qualitative agreement with experimental measurements for the ARCO SBA-II tower.

Research paper thumbnail of Monitoring process viscosities with a new on-line rheometer

Plastics Engineering, 1997

The versatile, rugged helical rheometer provides data in excellent agreement with off-line capill... more The versatile, rugged helical rheometer provides data in excellent agreement with off-line capillary rheometer data, and it can also handle fluids beyond the capabilities of conventional capillary and slit rheometers

Research paper thumbnail of KM Ng, R. Gani and WD Seider

Research paper thumbnail of Multiphase equilibria of reactive systems

Fluid Phase Equilibria, 1996

This paper reviews recent developments in the analysis and calculation of multiphase equilibria i... more This paper reviews recent developments in the analysis and calculation of multiphase equilibria involving chemical reactions. Emphasis is placed on the reaction tangent plane and its importance for stability analysis. Calculation methods to locate the global minimum of the Gibbs free energy are reviewed with emphasis on the GOP method that achieves ϵ-global convergence. Methods for the simulation and design of reactive-distillation columns are considered with emphasis on reactive azeotropes and reactive residue curves for chemical reactions at equilibrium or kinetically controlled.

Research paper thumbnail of Multiphase equilibria of reactive systems

This paper reviews recent developments in the analysis and calculation of multiphase equilibria i... more This paper reviews recent developments in the analysis and calculation of multiphase equilibria involving chemical reactions. Emphasis is placed on the reaction tangent plane and its importance for stability analysis. Calculation methods to locate the global minimum of the Gibbs free energy are reviewed with emphasis on the GOP method that achieves ϵ-global convergence. Methods for the simulation and design of reactive-distillation columns are considered with emphasis on reactive azeotropes and reactive residue curves for chemical reactions at equilibrium or kinetically controlled.

Research paper thumbnail of Retroreflective Articles and Devices Having Viscoelastic Lightguide

Research paper thumbnail of Method of making composite material

Research paper thumbnail of Incandescent Light Bulb:  Product Design and Innovation

Industrial & Engineering Chemistry Research, 2006

In this brief article, a strategy is introduced for meshing the technical advances with the fulfi... more In this brief article, a strategy is introduced for meshing the technical advances with the fulfillment of customer needs during the development and design of new products. The concept of an innovation map is developed to connect material, process, and product technologies to the value proposition of the new products. By retracing the advances in developing incandescent light bulbs, the interplay between technical discovery and its commercialization into new products is shown. Although the design of the incandescent light bulb is presented in hindsight, this interplay is the key to the design of new products; however, unfortunately, in new product design, there are many alternatives to explore that may not be fruitful.

Research paper thumbnail of Douglas, J. M., Conceptual Design of Chemical Processes, McGraw-Hill, 1988

Research paper thumbnail of Perspectives on chemical product and process design

Computers & Chemical Engineering, 2009

In this article, new perspectives and strategies of chemical product design are provided. Beginni... more In this article, new perspectives and strategies of chemical product design are provided. Beginning with the innovation map (Widagdo, S., Incandescent light bulb: Product design and innovation, Ind. Eng. Chem. Res., 45 (25), 8231-8233 (2006)) that links the critical technological advances necessary to meet customer needs, aspects of the Stage-Gate TM product-development process (SGPDP) are considered with emphasis on the concept, feasibility, and development stages. A focus is placed on the design of basic chemical products (e.g., commodity and specialty chemicals, pharmaceuticals, polymeric materials), industrial chemical products (e.g., films, fibers, paper, glass substrates, pastes, creams), and configured-consumer chemical products (e.g., light bulbs, hemodialysis devices, labs-on-a-chip). Perspectives on the role of process design in the context of product design are presented.

Research paper thumbnail of Nonlinear analysis in process design

AIChE Journal, 1991

As steady-state and dynamic simulators with optimal controllers have evolved, tools for nonlinear... more As steady-state and dynamic simulators with optimal controllers have evolved, tools for nonlinear analysis have been developed by reactor and thermophysical property specialists. Designers lag behind in developing and utilizing these tools, as many design strategies assume idealized behavior even though processes contain an increasing number of nonlinear elements. This article examines the sources of the nonlinear elements, often associated with physical and chemical interactions, in designs and their control systems. Promising methods for nonlinear analysis are revie wed. In each design activity, involving simulation, economic optimization, projections of controllability and operability, emphasis is on the sources of nonlinearities and solution methods. These are examined for the equality constraints and nonlinear programs in phase and chemical equilibria, in reactors and separators, and in the simulation and optimization of flowsheets. Also examined are the impact of nonlinear predictive control in screening designs and methods to insure operability, in the face of uncertainties.

Research paper thumbnail of Journal review. Azeotropic distillation

AIChE Journal, 1996

Recent and ongoing research in the distillation of nonideal mixtures is reviewed focus-ing on adv... more Recent and ongoing research in the distillation of nonideal mixtures is reviewed focus-ing on advances in the methodologies for the synthesis, design, analysis and control of separation sequences involvinghomogeneous and heterogeneous azeotropic towers. Maps of residue curves ...

Research paper thumbnail of Bifurcation analysis in heterogeneous azeotropic distillation

AIChE Journal, 1989

Parameterization with respect to the aqueous reflux ratio has been carried out for the steady-sta... more Parameterization with respect to the aqueous reflux ratio has been carried out for the steady-state analysis of a tower to dehydrate secbutanol using disecondary butyl ether as the entrainer. With an equilibrium-stage model, singularities are observed as the second liquid phase is introduced on the trays and regions of steady-state multiplicity are demonstrated. Furthermore, a critical aqueous reflux ratio, in the vicinity of which two liquid phases are introduced on most of the trays, varies only slightly with the number of trays in the tower. The model predicts that the product purities and recoveries remain high using one-third of the trays in the industrial SBA-II tower. Bifurcation analysis for a single stage does not explain these observations, and the effect of recycle is suspected.

Research paper thumbnail of Dynamic analysis of heterogeneous azeotropic distillation

AIChE Journal, 1992

A model and algorithm are presented for the separation of mixtures where the phase distribution o... more A model and algorithm are presented for the separation of mixtures where the phase distribution on the trays is extremely uncertain, as it occurs when the mixtures have two partially-miscible binary pairs and a minimum-boiling ternary azeotrope. Included are an algorithm for the consistent initialization of index-I differential/ algebraic equations, a novel algorithm for branch switching when the phase distribution changes at a real bifurcation point, and a reliable algorithm for phase stability analysis. Open-loop responses are presented for the dehydration of secbutanol with disecbutylether in single-stage, I2-tray, and 33-tray separators. These simulation results for the 33-tray tower are in qualitative agreement with experimental measurements for the ARCO SBA-II tower.

Research paper thumbnail of Monitoring process viscosities with a new on-line rheometer

Plastics Engineering, 1997

The versatile, rugged helical rheometer provides data in excellent agreement with off-line capill... more The versatile, rugged helical rheometer provides data in excellent agreement with off-line capillary rheometer data, and it can also handle fluids beyond the capabilities of conventional capillary and slit rheometers

Research paper thumbnail of KM Ng, R. Gani and WD Seider

Research paper thumbnail of Multiphase equilibria of reactive systems

Fluid Phase Equilibria, 1996

This paper reviews recent developments in the analysis and calculation of multiphase equilibria i... more This paper reviews recent developments in the analysis and calculation of multiphase equilibria involving chemical reactions. Emphasis is placed on the reaction tangent plane and its importance for stability analysis. Calculation methods to locate the global minimum of the Gibbs free energy are reviewed with emphasis on the GOP method that achieves ϵ-global convergence. Methods for the simulation and design of reactive-distillation columns are considered with emphasis on reactive azeotropes and reactive residue curves for chemical reactions at equilibrium or kinetically controlled.

Research paper thumbnail of Multiphase equilibria of reactive systems

This paper reviews recent developments in the analysis and calculation of multiphase equilibria i... more This paper reviews recent developments in the analysis and calculation of multiphase equilibria involving chemical reactions. Emphasis is placed on the reaction tangent plane and its importance for stability analysis. Calculation methods to locate the global minimum of the Gibbs free energy are reviewed with emphasis on the GOP method that achieves ϵ-global convergence. Methods for the simulation and design of reactive-distillation columns are considered with emphasis on reactive azeotropes and reactive residue curves for chemical reactions at equilibrium or kinetically controlled.