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Numerical Simulations Of Gas-Liquid Flow Dynamics In Bubble Columns, Deify Law, Francine Battaglia, Theodore J. Heindel Nov 2006

Numerical Simulations Of Gas-Liquid Flow Dynamics In Bubble Columns, Deify Law, Francine Battaglia, Theodore J. Heindel

Mechanical Engineering Conference Presentations, Papers, and Proceedings

There is great potential for using computational fluid dynamics (CFD) as a tool in scale-up and design of bubble columns. Full-scale experimentation in bubble columns is expensive and CFD is an alternative approach to study bubble column hydrodynamics. However, CFD can be computationally intensive as a predictive tool for a full three-dimensional geometry. In this paper, a 0.2 m diameter semi-batch bubble column is numerically simulated and the results are compared to experimental measurements performed by Rampure et al. [1]. The objectives are to examine and determine an appropriate set of numerical parameters and to determine if two-dimensional simulations ...


Three-Dimensional Path Planning Of Unmanned Aerial Vehicles Using Particle Swarm Optimization, Jung Leng Foo, Jared S. Knutzon, James H. Oliver, Eliot H. Winer Sep 2006

Three-Dimensional Path Planning Of Unmanned Aerial Vehicles Using Particle Swarm Optimization, Jung Leng Foo, Jared S. Knutzon, James H. Oliver, Eliot H. Winer

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Military operations are turning to more complex and advanced automation technology for minimum risk and maximum efficiency. A critical piece to this strategy is unmanned aerial vehicles (UAVs). UAVs require the intelligence to safely maneuver along a path to an intended target, avoiding obstacles such as other aircrafts or enemy threats. Often automated path planning algorithms are employed to specify targets for a UAV to fly to. To date, path-planning algorithms have been limited to two-dimensional problem formulations. This paper presents a unique three-dimensional path planning problem formulation and solution approach using Particle Swarm Optimization (PSO). The problem formulation was ...


Object-Centered Engineering: A Methodology For Virtual Engineering, Douglas S. Mccorkle, Kenneth M. Bryden, Daniel A. Ashlock Sep 2006

Object-Centered Engineering: A Methodology For Virtual Engineering, Douglas S. Mccorkle, Kenneth M. Bryden, Daniel A. Ashlock

Mechanical Engineering Conference Presentations, Papers, and Proceedings

In the product realization process, it is not currently possible to go from business case models to the final production system in the virtual design space. Virtual engineering aims to address this problem. Virtual engineering techniques will allow users to track the production of a product or system from birth to death, from the complete business case model to the customer’s feedback on the first production run. To implement a framework that will handle the broad range of information that is necessary to track a product through its complete life cycle, an object-centered approach involving virtual objects is required ...


Sharp: A System For Haptic Assembly And Realistic Prototyping, Abhishek Seth, Hai-Jun Su, Judy M. Vance Sep 2006

Sharp: A System For Haptic Assembly And Realistic Prototyping, Abhishek Seth, Hai-Jun Su, Judy M. Vance

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Virtual Reality (VR) technology holds promise as a virtual prototyping tool for mechanical assembly; however, several developmental challenges still need to be addressed before virtual prototyping applications can successfully be integrated into the product realization process. This paper describes the development of SHARP (System for Haptic Assembly & Realistic Prototyping), a portable VR interface for virtual assembly. SHARP uses physically-based modeling for simulating realistic part-to-part and hand-to-part interactions in virtual environments. A dual handed haptic interface for realistic part interaction using the PHANToM® haptic devices is presented. The capability of creating subassemblies enhances the application’s ability to handle a wide ...


Verve: A General Purpose Open Source Reinforcement Learning Toolkit, Tyler Streeter, James H. Oliver, Adrian Sannier Sep 2006

Verve: A General Purpose Open Source Reinforcement Learning Toolkit, Tyler Streeter, James H. Oliver, Adrian Sannier

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Intelligent agents are becoming increasingly important in our society in applications as diverse as house cleaning robots, computer-controlled opponents in video games, unmanned aerial combat vehicles, entertainment robots, and autonomous explorers in outer space. However, the broader adoption of intelligent agents is often hindered by their limited adaptability to new tasks; when conditions change slightly, agents may quickly become confused. Additionally, a substantial engineering effort is required to design an agent for each new task. This paper presents an adaptable, general purpose intelligent agent toolkit based on reinforcement learning (RL), an approach with strong mathematical foundations and intriguing biological implications ...


The Effect Of A Modified Downcomer On The Hydrodynamics In An External Loop Airlift Reactor, Samuel T. Jones, Theodore J. Heindel Jul 2006

The Effect Of A Modified Downcomer On The Hydrodynamics In An External Loop Airlift Reactor, Samuel T. Jones, Theodore J. Heindel

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Gas holdup and superficial liquid velocity in the downcomer and riser are studied for an external loop airlift reactor with an area ratio of 1:16. Two downcomer configurations are investigated consisting of the downcomer open or closed to the atmosphere. Experiments for these two configurations are carried out over a range of superficial gas velocities from UG = 0.5 to 20 cm/s using three aeration plates with open area ratios of 0.62, 0.99 and 2.22%. These results are compared to a bubble column operated with similar operating conditions. Experimental results show that the gas holdup ...


Similitude Analysis For Gas-Liquid-Fiber Flows In Cocurrent Bubble Columns, Chengzhi Tang, Theodore J. Heindel Jul 2006

Similitude Analysis For Gas-Liquid-Fiber Flows In Cocurrent Bubble Columns, Chengzhi Tang, Theodore J. Heindel

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Gas-liquid-fiber systems are different from conventional gas-liquid-solid systems in that the solid material (i.e., fiber) is flexible, has a large aspect ratio, and forms flocs or networks when its mass fraction is above a critical value. With its wide application to the pulp and paper industry, it is important to investigate the hydrodynamics of gas-liquid-fiber systems. In this paper, 19 parameters that influence gas holdup in gas-liquid-fiber bubble columns are critically examined and then a dimensional analysis based on the Buckingham Pi Theorem is used to derive the dimensionless parameters governing gas-liquid-fiber bubble column hydrodynamics. Seven dimensionless parameters that ...


Updating Mechanical Engineering Measurements And Instrumentation—A Case Study, Theodore J. Heindel Jun 2006

Updating Mechanical Engineering Measurements And Instrumentation—A Case Study, Theodore J. Heindel

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Measurement and instrumentation is a common course topic in many undergraduate mechanical engineering curricula. This paper summarizes changes to ME 370 – Engineering Measurements and Instrumentation at Iowa State University (ISU), which went through major course revisions from fall 2003 to spring 2005. Modifications to the course include the following: (i) incorporating virtual measurements and instrumentation into the lecture and laboratory, (ii) coupling the lecture and laboratory more closely through an on-line course manual, (iii) providing additional course resources through WebCT to enhance student learning, and (iv) updating and/or developing several new laboratory exercises to demonstrate key course learning objectives ...


Demonstrating Electromagnetic Noise In An Undergraduate Measurement And Instrumentation Course, David Muff, Theodore J. Heindel, Sriram Sundararajan Jun 2006

Demonstrating Electromagnetic Noise In An Undergraduate Measurement And Instrumentation Course, David Muff, Theodore J. Heindel, Sriram Sundararajan

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Electromagnetic noise (interference) is always present in a measurement system. The desire to minimize noise in your signal of interest can only be accomplished after the noise is properly identified. This paper summarizes a mechanical engineering undergraduate laboratory activity developed for ME 370 – Engineering Measurements and Instrumentation at Iowa State University. The goals of this activity are to (i) develop an understanding of how analog noise enters a measurement system and (ii) investigate several noise reduction methods. Students induce and measure capacitively coupled noise and investigate how the noise is related to noise source frequency and measurement circuit resistance. Methods ...


A Web-Based Interface For Complex Design Using A Virtual Engineering Software Framework, Kenneth J. Kopecky, David J. Muth Jr., Douglas S. Mccorkle, Eliot H. Winer, Kenneth M. Bryden May 2006

A Web-Based Interface For Complex Design Using A Virtual Engineering Software Framework, Kenneth J. Kopecky, David J. Muth Jr., Douglas S. Mccorkle, Eliot H. Winer, Kenneth M. Bryden

Mechanical Engineering Conference Presentations, Papers, and Proceedings

VE-Suite is a powerful software framework that allows many complex engineering tasks to be designed, analyzed, and optimized within a comprehensive virtual environment. VESuite is designed to enable the collaboration of engineers across distance and platforms, ranging from immersive Virtual Reality systems to common desktop computers. The purpose of this paper is to describe the development of a web-based interface for VE-Suite. Specific areas covered include the program’s facilities for data storage and retrieval, collaboration methods, and integration with the entire VE-Suite framework. The interface development is presented along with a test case shown within the software framework.


A Parallel Implementation Of Particle Swarm Optimization Using Digital Pheromones, Vijay Kalivarapu, Jung Leng Foo, Eliot H. Winer Jan 2006

A Parallel Implementation Of Particle Swarm Optimization Using Digital Pheromones, Vijay Kalivarapu, Jung Leng Foo, Eliot H. Winer

Mechanical Engineering Conference Presentations, Papers, and Proceedings

A parallel implementation of Particle Swarm Optimization (PSO) using digital pheromones to coordinate the movements of the swarm within an n-dimensional design space is presented in this paper. Digital pheromones are models simulating real pheromones emitted by insects for communication to indicate a source of food or a nesting location. This principle of communication and organization between each insect in a swarm offers substantial improvement when integrated into a Particle Swarm Optimization algorithm. Digital swarms are used to search a design space with digital pheromones aiding communication within the swarm to improve search efficiency. With statistical analysis, the pheromone strength ...


Implementation Of Digital Pheromones For Use In Particle Swarm Optimization, Jung Leng Foo, Vijay Kalivarapu, Eliot H. Winer Jan 2006

Implementation Of Digital Pheromones For Use In Particle Swarm Optimization, Jung Leng Foo, Vijay Kalivarapu, Eliot H. Winer

Mechanical Engineering Conference Presentations, Papers, and Proceedings

This paper presents a new approach to particle swarm optimization (PSO) using digital pheremones to coordinate the movements of the swarm within an n-dimensional design space. In traditional PSO, an initial randomly generated population swarm propagates towards the global optimum over a series of iterations. Each particle in the swarm explores the design space based on the information provided by previous best particles. This information is used to generate a velocity vector indicating a search direction towards a promising design point, and to update the particle positions. This paper presents how digital pheromones can be incorporated into the velocity vector ...


Multimodal Uav Ground Control System, Thomas Batkiewicz, K. C. Dohse, Vijay Kalivarapu, Thomas Dohse, Bryan Walter, Jared S. Knutzon, Derrick Parkhurst, Eliot H. Winer, James Oliver Jan 2006

Multimodal Uav Ground Control System, Thomas Batkiewicz, K. C. Dohse, Vijay Kalivarapu, Thomas Dohse, Bryan Walter, Jared S. Knutzon, Derrick Parkhurst, Eliot H. Winer, James Oliver

Mechanical Engineering Conference Presentations, Papers, and Proceedings

As unmanned units become more capable of self-control, and as their integration into our military forces increase, the role of the operator of these units is going to change. Current UAV ground control systems typically require to much of the operator’s attention per unit, and the role of the future operator will be more like that of a manager than that of a pilot. This paper describes research being done on a user interface for a future ground control system. Beginning with a visualization of a virtual battlefield, this next-generation UAV ground control system incorporates all available information and ...