Model-Based Control Of An Rcci Engine, Akshat Abhay Raut

Dissertations, Master's Theses and Master's Reports

Reactivity controlled compression ignition (RCCI) is a combustion strategy that offers high fuel conversion efficiency and near zero emissions of NOx and soot which can help in improving fuel economy in mobile and stationary internal combustion engine (ICE) applications and at the same time lower engine-out emissions. One of the main challenges associated with RCCI combustion is the difficulty in simultaneously controlling combustion phasing, engine load, and cyclic variability during transient engine operations.

This thesis focuses on developing model based controllers for cycle-to-cycle combustion phasing and load control during transient operations. A control oriented model (COM) is developed by using …

Multiscale Modeling: Thermal Conductivity Of Graphene/Cycloaliphatic Epoxy Composites, Sorayot Chinkanjanarot

Dissertations, Master's Theses and Master's Reports

The thermal property of epoxy as the binder in the Carbon Fiber (CF) composites, especially thermal conductivity is important to achieve the advance technology and to improve the performance of materials. Multiscale modeling including molecular dynamic (MD) modeling and micromechanical modeling is used to study the properties of neat Cycloaliphatic Epoxies (CE) and Graphene nanoplatelet (GNP)/CE with and without covalent functionalization.

The thermal properties (glass-transition temperature, thermal expansion coefficient, and thermal conductivity) and mechanical properties of CE system are investigated by MD modeling using OPLS-All Atom force field. A unique crosslinking technique is developed to achieve the cured CE models …

Modeling Mass And Thermal Transport In Thin Porous Media Of Pem Fuel Cells, Vinaykumar Konduru

Dissertations, Master's Theses and Master's Reports

Water transport in the Porous Transport Layer (PTL) plays an important role in the efficient operation of polymer electrolyte membrane fuel cells (PEMFC). Excessive water content as well as dry operating conditions are unfavorable for efficient and reliable operation of the fuel cell. The effect of thermal conductivity and porosity on water management are investigated by simulating two-phase ow in the PTL of the fuel cell using a network model. In the model, the PTL consists of a pore-phase and a solid-phase. Different models of the PTLs are generated using independent Weibull distributions for the pore-phase and the solid-phase. The …

Development Of An Evaporation Sub-Model And Simulation Of Multiple Droplet Impingement In Volume Of Fluid Method, Sathya Prasad Potham

Dissertations, Master's Theses and Master's Reports

Droplet collision and impingement on a substrate are widely observed phenomenon in many applications like spray injection of Internal Combustion Engines. Existing Lagrangian models do not provide a comprehensive picture of the outcome of these events and may involve model constants requiring experimental data for validation. Physics based models like Volume of Fluid (VOF) method involve no parametric tuning and are more accurate. The aim of this thesis is to extend the basic VOF method with an evaporation sub-model including an additional vapor phase and implement this model in an open source Computational Fluid Dynamics (CFD) software, OpenFOAM. The new …

Assessment Of Annular Flow Boiling In The Context Of Computational Fluid Dynamics (Cfd) Simulations, Experiments, And Existing Correlations, Hrishikesh Prasad Ranga Prasad

Dissertations, Master's Theses and Master's Reports

The main objective of the current work is to achieve a better understanding – through modeling and simulation/programming activities – of annular flow-boiling and its applications based on a synthesis of Computational Fluid Dynamics (CFD) simulations, existing correlations, and experiments. A unique and rigorous 2-D CFD simulations technique was developed for annular flow-boiling to propose a correlation for convective component of Heat Transfer Coefficient (HTC) – defined here as flow-boiling in the absence of nucleation. To provide a context for the correlation structure of convective component of HTC, flow-physics details of annular flow-boiling and correlation structure (based on fundamental considerations) …

The Impact Of Water Injection On Spark Ignition Engine Performance Under High Load Operation, Jeremy Worm

Dissertations, Master's Theses and Master's Reports

An experimental effort has been completed in which water injection was investigated as a means of enabling increases in engine output and high load efficiency. Water was injected into the intake port of a direct fuel injected, 4-cylinder, boosted engine with dual independent variable valve timing. The water was shown to increase volumetric efficiency and decrease the onset of knock which in turn enable more optimal combustion phasing. Both of these affects resulted increases in load of up to 5.5% at the same manifold pressure as the baseline case. The advancement of combustion phasing, combined with elimination of fuel enrichment …

Influence Of Magnetic Nanoparticles And Magnetic Stress On An Ionic Liquid Electrospray Source, Kurt Joseph Terhune

Dissertations, Master's Theses and Master's Reports

Two electrospray sources were developed to operate on an ionic liquid ferrofluid; one source was a pressure‑fed capillary electrospray source and the other was a novel electrospray source which used a magnetically‑induced instability to produce a peak from which an electric field could extract electrospray. Multiple characteristics of electrospray operation were examined for both sources using faraday plates/cups, a quartz crystal microbalance, a retarding potential analyzer, and a time-of-flight mass spectrometer. The ILFF electrosprays for a capillary source were shown to operate in a mixed ion/droplet regime. The mass flow of the electrospray beam was primarily transported by larger particles …

Investigation Of Rope Formation In Gas–Solid Flows Through A 90° Pipe Bend Using High-Speed Video And Cfd Simulations, Sai S. Guda, Steven L. Rowan, Tao Yang

Faculty & Staff Scholarship

A study of rope formation in gas–solid flows through abrupt turns has been conducted. Experiments in which high-speed video was recorded and analyzed for solid concentration profiles were compared to CFD simulations utilizing both RANS and large eddy simulation turbulence models. In both simulations and experiments, particle-laden flows of air and ground flaxseed, with solid loadings of 35, 42, and 51% were considered. The results of the study demonstrate that both RANS and large eddy simulation can accurately predict particle roping. Furthermore, simulations show that the roping phenomenon is strongly dependent upon selection of an appropriate value for the coefficient …

Mechanically Activated Magnesiothermic Combustion Synthesis Of Zirconium And Hafnium Diborides, Sergio Cordova

Open Access Theses & Dissertations

Magnetohydrodynamic (MHD) generation of electric power has the potential to increase the thermal efficiency of fossil-fuel burning power plants. Electrode materials in MHD generators must possess a high melting point, high electrical and thermal conductivities, chemical stability, and resistance to thermal shock, oxidation, and plasma sparks/arcs. Ultra-high temperature ceramics based on diborides of zirconium and hafnium (ZrB2 and HfB2) are promising materials for this application. Self-propagating high-temperature synThesis (SHS) is an attractive method for their large-scale fabrication, but SHS of ZrB2 and HfB2 from elemental Zr, Hf, and B is not economically viable because of the high cost of the …

Simulations Of Impinging Jet With A Range Of Configuration, Devansh Singh

Electronic Theses and Dissertations

Impinging jet technique is widely increasing across the globe due to its ability to produce high heat and mass transfer as compared to other traditional methods. Three cases of impinging jets related to cooling technologies for a gas turbine were investigated. The first case involves a single jet impinging on a flat plate. The second case has an array of jets impinging on a curved surface. The third case deals with simulating impinging jet in crossflow. The first case was used for validation and shows the effect of mesh and inlet boundary conditions. After careful observation, it was seen that …

Cfd Analysis Methods For Systems Driven By Natural Convection, Aaron Propst

Electronic Theses and Dissertations

Natural convection driven flows are present in many engineering applications such as HVAC, electronics cooling, and cryogenic systems. Predicting the flow behavior of such systems requires experimentation or numerical simulation through Computational Fluid Dynamics due to the complex interactions of natural convection. Recent advances in computing resources have made CFD increasingly popular for engineering analysis of fluid dynamics and heat transfer. CFD simulation has several advantages over experimentation including: 1) cost, 2) ease of changing design parameters, and 3) time required to obtain results. These advantages lead to an increased likelihood of discovering an optimal design. However, systems with complex …

Evaluating Discretization Errors With Numerical Experiments, David Dodoo-Amoo, Julio Cesar Mendez, Dehau Feng, Frederick Ferguson

Early Career Technical Journal (ECTJ)

Section 5: Materials; pp. 134-141

Lighted Ear Curette, Kaitlin Klotzle, Kelsey Ashmore, Crysta Yamamoto, Katrina Elfrink, Cynthia Stoller

Williams Honors College, Honors Research Projects

The ear canal is a sensitive and small part of the human body that is prone to accumulate cerumen or lodge foreign bodies. In order to clean the ear canal or remove foreign bodies, three hands are required: one to brace the patient's head, one to maneuver the curette that is used to clean the ear, and one to hold a light source in order to make the small, dark area visible. Therefore, a design is needed that can allow a doctor to safely clean an ear with an instrument that only requires two hands. Furthermore, the design must have …

Water Jet Cutting Head Actuator, Jacob D. Augustynovich

Williams Honors College, Honors Research Projects

In an effort to increase efficiency and productivity, WARDJet was seeking a better actuation method for the cutting head on their waterjets. Current actuation methods were, for the most part, purely mechanical, relying on compressed air, springs, and water pressure to open and close the valve to 60,000 psi of water. Increasing the speed of the on/off cycle times of the waterjet would allow for faster movements of the cutting head from one cut to the next, increasing the overall amount of products cut in a day, week, and year. This obviously points to increased sales, increased profit, and increased …

Wardjet Waterjet Cutting Head Actuator Design, Micah Steiner, Jacob D. Augustynovich, Benjamin Heckert

Williams Honors College, Honors Research Projects

In an effort to increase efficiency and productivity, WARDJet was seeking a better actuation method for the cutting head on their waterjets. Current actuation methods were, for the most part, purely mechanical, relying on compressed air, springs, and water pressure to open and close the valve to 60,000 psi of water. Increasing the speed of the on/off cycle times of the waterjet would allow for faster movements of the cutting head from one cut to the next, increasing the overall amount of products cut in a day, week, and year. This obviously points to increased sales, increased profit, and increased …

The Design And Testing Of A High Performance Formula Sae Powertrain, Ryan T. Harty

Williams Honors College, Honors Research Projects

Every year the Society of Automotive Engineers (SAE) tasks collegiate students with designing, constructing, testing, and competing with an open wheel formula style racecar. This vehicle has to meet stringent technical requirements that are provided in a rule book published by SAE. The Formula SAE (FSAE) rule book is a very comprehensive set of requirements that are centered on safety of the driver of the vehicle and the safety of the track workers. The students are required to read and understand the rulebook in order to use sound engineering practices to build not only a high performing vehicle but a …

Optimization Of Acoustic Soundboard Through Modal Analysis And Material Selection, Noah C. Nicholas, Cody Gruber, Nicholas Hartman

Williams Honors College, Honors Research Projects

The purpose of this design project was to determine if it is plausible to design an acoustic top plate assembly made of a non-traditional material which is equivalent in sound quality to that of a standard wooden guitar. Since wood must be crafted by skilled luthiers, the overall cost of producing the completed product is fairly high. To reduce the cost of a finished acoustic guitar, we proposed to alter the material to that of one that is easier to manufacture, such as plastics and composites.

Based on our research, our team chose to test both ABS plastic and carbon …

Swagelok's Hand Tube Bender, Chapin Hutama, Seth Bills, William Mcconnell, Tyler Brown

Williams Honors College, Honors Research Projects

In our project, we are assigned to develop a hand tube bender that is able to bend medium, high pressure, and standard 1/4” and 3/8” tubing. The bender also shall be capable of being used with two hands without the aid of a bench vise and have provisions for use in a bench vise for convenience. The bender shall not damage the tube during bending and induce a maximum of 8% ovality in the bent tubing. In addition, the cost of the bender shall be less than the existing hand tube bender and be resistant to rusting from ordinary use. …

Analysis And Sensitivity Study Of Zero-Dimensional Modeling Of Human Blood Circulation Network, Roussel Rahman

Browse all Theses and Dissertations

The systemic circulation has a large number of vessels; therefore, 3-D simulation of pulse-wave propagation in the entire cardiovascular system is difficult and computationally expensive. Zero-Dimensional (Zero-D) and One-Dimensional (1-D) models are simplified representations of the cardiovascular network; they can be coupled as supplements to regional 3-D models for closed-loop multi-scale studies or be simulated as self-sufficient representations of the blood-flow network. Unlike Zero-D models, 1-D models can provide linear space-wise information for the vessels. However, Zero-D models can prove to be more useful in particular cases; as flexibility in adjusting parameters facilitate in tailoring the model to specific needs. …

An Investigation On The Stress Intensity Factor Of Surface Micro-Cracks, Sirisha Divya Arli

Browse all Theses and Dissertations

The contact fatigue failure in the form of micro or macro-scale pitting is an important failure mode for rolling mechanical elements, such as bearings and gears that are widely used in the automotive, aerospace and wind turbine fields. The micro-pitting process in some cases, gradually removes the surface material through fatigue wear, altering the geometry of the contact surfaces to alleviate the contact pressure decelerating the continued pitting rate. The propagation of the micro-cracks in other cases, goes deep into the material along a shallow angle, turns parallel to the surface at a certain depth, where the maximum shear or …

One Dimensional Computer Modeling Of A Lithium-Ion Battery, Ashwin S. Borakhadikar

Browse all Theses and Dissertations

Renewable energy storage is vitally important to many applications for which batteries are the finest choice. As energy storage technology may be applied to a number of areas that differ in power and energy requirements, modeling of battery performance is required. In recent years, a lot of research has been done in this area but, the earliest model was designed by Marc Doyle, T. F. Fuller, and J. Newman in 1993. This work involves the development of a one-dimensional computer model of a lithium-ion battery which consists of three domains: the negative electrode, the separator, and the positive electrode. The …

Dynamic Modeling Of Thermal Management System With Exergy Based Optimization, Marcus J. Bracey

Browse all Theses and Dissertations

System optimization and design of aircraft is required to achieve many of the long term objectives for future aircraft platforms. To address the necessity for system optimization a vehicle-level aircraft model has been developed in a multidisciplinary modeling and simulation environment. Individual subsystem models developed exclusively in MATLAB-SimulinkTM, representing the vehicle dynamics, the propulsion, electrical power, and thermal systems, and their associated controllers, are combined to investigate the energy and thermal management issues of tactical air vehicle platforms. A thermal vehicle level tip-to-tail model allows conceptual design trade studies of various subsystems and can quantify performance gains across the aircraft. …

Nfpa Fluid Power Vehicle Challenge, Ean H. Dickerhoof

Williams Honors College, Honors Research Projects

Every year the National Fluid Power Association hosts a Fluid Powered Vehicle Challenge, this exposes students from universities all around the United States to the power and possibilities of hydraulics. This year the University of Akron’s team of engineers set out to design a bicycle that would be competitive and innovative in all aspects of the competition. In order to accomplish this, the designed bicycle must excel in three categories of competition; a sprint race, an endurance race, and an efficiency challenge.

To accomplish this task the University of Akron’s team of engineers used a lightweight bicycle frame with many …

Chocolate Bar Wrapping Machine, Austin M. Hoff, Daniel R. Trepke, Caleb B. Krichbuam

Williams Honors College, Honors Research Projects

Gilbert Chocolates has proposed to manufacture a machine to wrap chocolate bars. This machine is intended to replace two people wrapping the chocolate bars by hand, which is a time consuming method. This is especially apparent between October and January when the workers are working long hours in preparation for the Christmas rush of customers. Currently wrapping a bar takes about a minute and Gilbert Chocolates wants this time reduced down to 20-30 seconds. The budget for this project is set at $1000, and is being funded by the company. This machine needs to fit in a cubic foot of …

Instruction Pamphlet Insertion Machine, Jim Griggs, Scott Miller, Michael Kubala

Williams Honors College, Honors Research Projects

Weaver Industries in Akron, Ohio provided us with our senior design project. Weaver Industries seeks individuals with disabilities and provides them with job opportunities. One of their products is a “Kong” dog toy. As of now, the instruction pamphlet that comes with this dog toy is placed into each piece of packaging individually by hand. We are tasked with automating this process. Two years ago, a group of students worked on this project, but the reliability of their prototype was only around 60-70%. Then last year, another group of students worked on this project, but again, the reliability of their …

Lawn Mower Lift, Randall E. Schelcher

Williams Honors College, Honors Research Projects

Our team of engineers were given the task of coming up with a design project and designing the system, creating calculations, and brainstorming ideas. We set out to design a riding lawn mower lift. The purpose of this design was to assist in general maintenance like replacing blades, oil changes, etc.

To accomplish this task, our team started to brainstorm ideas and make sketches to look at all the options. We then did research and looked at different size lawn mowers and looked at the specifications. This helped our team to be able to design the size of platform needed …

Study Of Periodical Flow Heat Transfer In An Internal Combustion Engine, Xi Luo

Wayne State University Dissertations

In-cylinder heat transfer is one of the most critical physical behaviors which has a direct influence on engine out emission and thermal efficiency for IC engine. In-cylinder wall temperature has to be precisely controlled to achieve high efficiency and low emission. However, this cannot be done without knowing gas-to-wall heat flux. This study reports on the development of a technique suitable for engine in-cylinder surface temperature measurement, as the traditional method is “hard to reach.” A laser induced phosphorescence technique was used to study in-cylinder wall temperature effects on engine out unburned hydrocarbons during the engine transitional period (warm up). …

Additive Manufacturing Of Al 4047 And Al 7050 Alloys Using Direct Laser Metal Deposition Process, Amrinder Singh

Wayne State University Dissertations

Additive manufacturing (AM) of metals is finding numerous applications in automotive and aerospace industry. In 21st century, aluminum is second to steel in automotive sector, because of its high strength to weight ratio. In current era, casted components of Al-Si alloy and high strength Al 7xxx series alloys are being used from low load to high load components. The primary study of this research was to achieve the defect free deposition of Al-Si and Al 7050 alloy. Al-Si alloys samples have been manufactured at lab scale using various additive manufacturing processes, but so far there is no literature available to …

Development Of A Dynamic Cfd Model For Offshore Oscillating Water Columns With Non-Linear Interactions, Ken O'Connell

Theses

This thesis focuses on the development of a state of the art modelling technique for offshore Oscillating Water Column (OWC) type Wave Energy Converters (WEC) using Computational Fluid Dynamics (CFD). Current literature indicates a limited amount of work has been completed on studying these devices containing non-linear time dependent flow phenomenon. Initially, a 2D Numerical Wave Tank (NWT) is studied to reduce discretisation error in order to reproduce accurately propagating waves. Further development into a 3D domain permits the geometrical requirements of an OWC type spar buoy to be included.

In parallel, a single Degree of Freedom (DOF) model is …

Tractor Test 2172: John Deere 8400r E23, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …