Predictive Control Of Power Grid-Connected Energy Systems Based On Energy And Exergy Metrics, Meysam Razmara

Dissertations, Master's Theses and Master's Reports

Building and transportation sectors account for 41% and 27% of total energy consumption in the US, respectively. Designing smart controllers for Heating, Ventilation and Air-Conditioning (HVAC) systems and Internal Combustion Engines (ICEs) can play a key role in reducing energy consumption. Exergy or availability is based on the First and Second Laws of Thermodynamics and is a more precise metric to evaluate energy systems including HVAC and ICE systems. This dissertation centers on development of exergy models and design of model-based controllers based on exergy and energy metrics for grid-connected energy systems including HVAC and ICEs.

In this PhD dissertation, …

Experimental Investigation Of Fast Pyrolysis Of Arundo Donax In A Novel Paddle Reactor, Chintan Desai

Dissertations, Master's Theses and Master's Reports

The main objective of this research was to show the effectiveness of a novel paddle reactor for fast pyrolysis and study the effect of biomass particle size and reaction temperature of Arundo Donax a type of energy crop on the bio-oil yields. The novel paddle reactor showed effective mixing and heat transfer which were proved with the help of studying the residence time and the heating characteristics of the system respectively. The effect of different biomass particle sizes on the bio-oil yield was not significant, the bio-oil yield was approximately 50% for all the sizes. For Arundo Donax particle sizes …

Low Temperature Split Injection Spray Combustion: Ignition, Flame Stabilization And Soot Formation Characteristics In Diesel Engine Conditions, Ahmed Abdul Moiz

Dissertations, Master's Theses and Master's Reports

The aim of the PhD work is to investigate the fundamental differences in combustion behavior when split injections are used in low temperature combustion regime. In this thesis, the first injection is also called as pilot injection and second injection is also called as main injection. The broad aspects which are studied encompassing the investigation is to study the ignition delay, lift-off and soot formation of such a double split spray combustion. The mechanisms of ignition, lift-off and soot production are to be studied since the main ignition and lift-off were found to differ from the pilot which effect net …

Design Of Real-Time Combustion Feedback System And Experimental Study Of An Rcci Engine For Control, Jayant Kumar Arora

Dissertations, Master's Theses and Master's Reports

Premixed compression ignition (PCI) technologies offer high efficiency and low emissions but are usually confined by limited operation range as well as high pressure rise and heat release rate. In this work, a more recently developed PCI mode is explored where in-cylinder blending of two fuels with different auto-ignition characteristics (diesel and gasoline) is utilized to create reactivity stratification such that heat release rate and combustion timing can be controlled. This mode has been defined as Reactivity Controlled Compression Ignition (RCCI).

As part of this thesis, the main aim is to study various parameters that can be used to control …

An Experimental Investigation Of The Effect Of Temperature And Space Velocity On The Performance Of A Cu-Zeolite Flow-Through Scr And A Scr Catalyst On A Dpf With And Without Pm Loading, Vaibhav Kadam

Dissertations, Master's Theses and Master's Reports

Abstract The heavy-duty diesel (HDD) engines use the diesel oxidation catalyst (DOC), catalyzed particulate filter (CPF) and urea injection based selective catalytic reduction (SCR) systems in sequential combination, to meet the US EPA 2010 PM and NOₓ emission standards. The SCR along with a NH₃ slip control catalyst (AMOX) offer NOₓ reduction >90 % with NH₃ slipHowever, there is a strong desire to further improve the NOₓ reduction performance of such systems, to meet the California Optional Low NOₓ Standard implemented since 2015. Integrating SCR functionality into a diesel particulate filter (DPF), by coating the SCR catalyst on the DPF, …

Economical Retrofit System To Reduce Cooking Emissions In Third World Dwellings, Jonathan Vanzummeren, Tyler Sturgeon, Ben Dalessandro

Williams Honors College, Honors Research Projects

Abstract:

The purpose of this document is to propose and demonstrate the feasibility and effectiveness of substituting an open flame biomass cooking process with a closed system with the capabilities of sustaining an adequate fire. Clay ovens or “chulhas” are the traditional piece of cooking equipment used in poorer areas of the world. They are often built inside cramped one-room housing units with little or no ventilation. The emissions released from burning fuel sources such as wood, coal, or animal waste bring with them detrimental and often fatal health problems and results in approximately 1.3 million deaths per year.

The …

Competition Vehicle Based Intake Manifold Design, Joshua N. Matiash

Dissertations, Master's Theses and Master's Reports

A competitive vehicle in Formula SAE needs to be easy for unskilled drivers to extract the maximum performance from. This requires a predictable and manageable torque curve. This report details the development of an intake manifold for a Formula SAE car from a vehicle-based approach to produce this manageable and predictable torque. The current vehicle was instrumented and driven on a representative track to determine the usage of available torque. Based on these findings an ideal torque curve was chosen that favored increased torque at upper engine speed ranges and decreased torque at lower engine speed ranges. A 1-D engine …

Experimental Study, Modelling And Controller Design For An Rcci Engine, Naga Nithin Teja Kondipati

Dissertations, Master's Theses and Master's Reports

Low Temperature Combustion (LTC) has got widespread attention over the past two decades in the field of Automotive Research and Development due to it’s potential for achieving higher efficiencies with near-zero engine out NOx and soot emissions. Among all the LTC strategies Reactivity controlled compression ignition (RCCI) has shown the most promising results due to it’s precise control over combustion phasing and heat release rate. However, RCCI being a dual-fuel stratified combustion, precise control over the injection timing of direct injected fuel and in-cylinder fuel reactivity of the mixture needs to be controlled effectively in order to achieve gross indicated …

An Assessment Of The Validity Of The Kinetic Model For Liquid-Vapor Phase Change By Examining Cryogenic Propellants, Kishan Bellur

Dissertations, Master's Theses and Master's Reports

Evaporation is ubiquitous in nature and occurs even in a microgravity space envi- ronment. Long term space missions require storage of cryogenic propellents and an accurate prediction of phase change rates. Kinetic theory has been used to model and predict evaporation rates for over a century but the reported values of accommodation coefficients are highly inconsistent and no accurate data is available for cryogens. The proposed study involves a combined experimental and computational approach to ex- tract the accommodation coefficients. Neutron imaging is used as the visualization technique due to the difference in attenuation between the cryogen and the metallic …

Final Project Report: Heliostat-Concentrator Solar Cooker, Ian Davison, Devin Mast

Mechanical Engineering

This document is the full report for the senior project of Cal Poly Mechanical Engineering students Ian Davison and Devin Mast. The report encompasses the full project process, including background research, identification of need, design requirements, design development, proposed design, design realization, changes to proposed design, and design verification. We were tasked with the design and manufacture of a “dual mirror” solar cooker to verify a concept for a new type of off-axis parabolic solar cooker conceived by Dr. Pete Schwartz, the sponsor of the senior project and a physics professor at Cal Poly. Previously, off-axis parabolic solar cookers have …

High Temperature Hepa Filter Test Unit Upgrades, Alexander Krippner, Ian Corcorran, Michael Burlando

Mechanical Engineering

No abstract provided.

Evaluation Of Two-Phase Evaporation Pressure Drop Correlations For Low Refrigerant Mass Flux., Anna Fenko

Electronic Theses and Dissertations

This study was conducted to evaluate three currently popular two-phase pressure drop models for extremely low velocity refrigerant flow through smooth circular evaporators in household refrigeration systems. Experimental data was taken at mass fluxes under 70 kg/m²s for two refrigerants, R134A and R600A, internal diameters of aluminum evaporators ranging from 0.186 to 0.317 inches, U-bend internal radii ranging from 0.342 to 0.750 inches in horizontal and vertical orientations of evaporators. The geometry of the samples closely resembled a commonly used serpentine shape with multiple U-bends experiencing both, up- and down-flow of the refrigerant. Two empirical models, Müller-Steinhagen & …

Simulation Of An Air Cooled Single-Effect Solar Absorption Cooling System With Evacuated Tube Collectors, Mohsen Jahandardoost

UNLV Theses, Dissertations, Professional Papers, and Capstones

Consistently increasing CO2 emission and ozone depletion from synthetic refrigerants are serious environmental issues challenging the scientific community. Absorption cooling systems give scope of utilizing low grade energy source for generating cooling effect. Solar energy is one of these low grade energy sources and with considering the fact that cooling demand increases with the intensity of solar radiation, solar refrigeration has been considered as a logical solution.

This thesis consists of two different simulation stages, in the first stage, a single effect lithium bromide absorption cooling system with constant cooling capacity is modeled and the effect of ambient and generator …

Axisymmetric Bi-Propellant Air Augmented Rocket Testing With Annular Cavity Mixing Enhancement, Allen A. C. Capatina

Master's Theses

Performance characterization was undertaken for an air augmented rocket mixing duct with annular cavity configurations intended to produce thrust augmentation. Three mixing duct geometries and a fully annular cavity at the exit of the nozzle were tested to enable thrust comparisons. The rocket engine used liquid ethanol and gaseous oxygen, and was instrumented with sensors to output total thrust, mixing duct thrust, combustion chamber pressure, and propellant differential pressures across Venturi flow measurement tubes.

The rocket engine was tested to thrust maximum, with three different mixing ducts, three major combustion pressure sets, and a nozzle exit plane annular cavity (a …

An Energy Cube Project For Teaching Engineering Design Process, Fionnuala Farrell, Shannon Chance, Micheal O'Flaherty

Conference papers

This year, the College of Engineering and the Built Environment at our institute inaugurated a new Common First Year design project module that helps inform students in the selection of a specific engineering discipline. Each student, prior to selecting their bachelor’s specialism, completes three group-based design projects: a bridge design project (to familiarise students with civil and structural engineering), a RoboSumo project (involving robotics, programming, electrical and electronics engineering), and an Energy Cube project (introducing fundamentals of mechanical, manufacturing and design, and building services engineering). This paper focuses on how the engineering design process was taught via the Energy Cube. …

Improvement Of Diesel Engines At High Speeds Via Flexible Valve Actuation And Cylinder Deactivation, Dina M. Caicedo Parra, Gregory M. Shaver, Aswin Ramesh

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the U.S fuel consumption is expected to increase over 20% from 2010 to 2020 especially in the heavy duty segment. As a consequence of the increase in production of heavy and light duty vehicles, regulations and stricter policies are being applied to the emissions of pollutants, including NOx, and soot. This study outlines strategies for using cylinder deactivation and intake valve closure (IVC) modulation to improve fuel economy and increase the rate at which NOx/soot-mitigating aftertreatment devices reach working temperatures. Effects of opening and squeezing variable geometry turbine (VGT) turbocharger were also analyzed. From the results it was observed …

Assessment Of Critical Technologies For Gas Turbine Engines Using Numerical Tools, Vinicius Pessoa Mapelli, Guillermo Paniagua, Jorge Sousa

The Summer Undergraduate Research Fellowship (SURF) Symposium

In 2014 gas turbine engine has reached a market value of 82.5 billion dollars, of which 59.5% are related to aircraft propulsion. The continuous market expansion attracts more and more the interest of researchers and industries towards the development of accurate numerical techniques to model thermodynamically the entire engine. This practice allows a performance and optimization analysis before the actual experimental testing, reducing the time and required investment in the design of a new engine. In this paper, a recently developed open source numerical tool named “Toolbox for the Modeling and Analysis of Thermodynamic Systems” (T-MATS) is used to assess …

Combustion Wave Propagation Enhancement Of A Nitrocellulose Solid Monopropellant, Omar R. Yehia, Shourya Jain, Li Qiao

The Summer Undergraduate Research Fellowship (SURF) Symposium

Improvement and control of the burning behavior and characteristics of solid fuels promise improved performance of systems ranging from solid rocket motors to microelectromechanical systems. Introducing methods to enhance combustion wave propagation velocities of solid propellants is a crucial step in realizing improved performance in rocket motors that use organic nitrate-based propellants. This work aims to enhance the burning characteristics of solid fuels through the use of thermally guided combustion waves. In order to increase the burning rate of solid nitrocellulose fuel layers, graphite sheets were used as thermally conductive bases in order to substantially improve heat transfer to unburned …

High Pressure Combustion And Supersonic Jet Ignition For H2/Air, Michael G. Woodworth, Sayan Biswas, Li Qiao

The Summer Undergraduate Research Fellowship (SURF) Symposium

There are many incentives to increase the fuel efficiency of combustion processes. This paper looks at two available options to achieve this goal. The former aims to develop an experimental method that can analyze combustion at extremely high pressures to improve the understanding of high pressure H2/air combustion. Experimental data has been lacking a suitable combustion diagnostic to visualize high pressure combustion processes, making it difficult to improve the process. Improvement of x-ray diffraction tomography in a windowless combustor makes it possible to see flame propagation at high pressure. The procedure and chamber are still in the design phase, yet …

3d Printing Nanostructured Thermoelectric Device, Qianru Jia, Collier Miers, Amy Marconnet

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermoelectric materials convert thermal energy to electrical energy and vice versa. Thermoelectrics have attracted much attention and research efforts due to the possibility solving electronic cooling problems and reducing energy consumption through waste heat recovery. The efficiency of a thermoelectric material is determined by the dimensionless figure of merit ZT, which depends on both thermal and electrical properties. Researchers have worked for several decades to improve the ZT, but there had been little progress until nanomaterials and nanofabrication became widely available. Nanotechnology makes the ZT enhancement attainable by disconnecting the linkage between thermal and electrical transport. Printing customized, flexible thermoelectric …

Altered Combustion Characteristics Of Aluminum Fuels Through Low-Level Fluoropolymer Inclusions With And Without In Situ Nanoaluminum., Courtney K. Murphy, Brandon Terry, Steven F. Son

The Summer Undergraduate Research Fellowship (SURF) Symposium

Aluminum inclusions have been widely used to increase the specific impulse of solid rocket propellant. However, issues arise with the addition of aluminum in the form of agglomeration, which can cause kinetic and thermal losses (i.e., two-phase flow losses) through the nozzle, which can reduce motor performance by as much as 10%. Reduction of agglomerate size may reduce the effect of two-phase flow losses. Polytetrafluoroethylene (PTFE or Teflon^TM) inclusions into aluminum via mechanical activation (MA, milling) have been shown to produce a smaller coarse agglomerate size due to microexplosion of the composite particles at the propellant surface. Perflouroalkoxy …

The Effects Of Ivc Modulation On Modern Diesel Engines Equipped With Variable Valve Actuation At High Load And Speed, Troy E. Odstrcil, Gregory M. Shaver, Cody M. Allen

The Summer Undergraduate Research Fellowship (SURF) Symposium

Modern diesel compression engines are known for their increased durability, fuel economy and torque when compared with their spark ignition gasoline counterparts. These are some of the reasons why diesel engines are preferred in heavy duty applications such as trains and semi-trucks. During the Heavy Duty Federal Test Procedure transient drive cycle, or HDFTP, nearly 85% of the total fuel burned is at speeds greater than 2000 revolutions per minute (RPM) for the studied engine. Therefore, it is desirable to increase the fuel economy at these loads and speeds. It is hypothesized that the use of late intake valve close …

Numerical Solver For Multiphase Flows, Victor C B Sousa, Carlo Scalo

The Summer Undergraduate Research Fellowship (SURF) Symposium

The technological development of micro-scale electronic devices is bounded by the challenge of dissipating their heat output. Latent heat absorbed by a fluid during phase transition offers exceptional cooling capabilities while allowing for the design of compact heat exchangers. The understanding of heat transport dynamics in the context of multiphase flow physics is hampered by the limited access to detailed flow features offered by experimental measurements. Computational Fluid Dynamics (CFD) can overcome such difficulties by providing a complete description of the three-dimensional instantaneous flow field. Unfortunately, the majority of the numerical investigations in this field at Purdue are carried out …

Modeling Radiation Heat Transfer For Building’S Cooling And Heating Loads: Considering The Role Of Clear, Cloudy, And Dusty Conditions In Hot And Dry Climates, Salem Ahmed Algarni

Graduate Theses and Dissertations

The influence of transient factors such as sky long wave radiation exchange and atmospheric aerosols (i.e., smog, and dust – made up of sand, clay, and silt) are not carefully considered in current building design and simulation models. Therefore, the research objective was to better understand and account for such variables, resulting in improved radiative predictive capabilities, especially important for hot and dry climates under different sky conditions including clean, cloudy, and dusty. Overall, results of this dissertation provided a better prediction method for sky long wave radiation exchange with a building’s roof and the impact of dust accumulation on …

The Future Of Rural Communities, Alondra B. Perez, Yanliang Zhang (Mentor)

Idaho Conference on Undergraduate Research

There is a problem in how modern energy is being distributed throughout the world; less than a quarter of the population have access to energy. Limited energy access is seen in rural areas because of the costs that comes from transporting material and making modern energy resources (solar panels, wind turbines, etc..). Through research on thermoelectric devices, there have been many theories tested in order to improve energy efficiency focusing on easy maneuverable resources. At Boise State’s Advanced Energy Lab, thermoelectric generators are being created and modified which can be used to help communities from rural areas power utilities needed …

Active Fog Catcher, Michael Giglio, Carson Hand, William Beechinor, Kai Zhang

Mechanical Engineering

The active fog catching senior project team has been asked to develop a device that will harvest water from the atmosphere, namely fog, using active means. The project will be centered on maximizing water collection rate, with efficiency as a secondary concern. The final design utilizes a refrigeration system in which fans pull air across the cold evaporators inside of a duct. Water condenses on the evaporators and drain into a collection container. It was decided to focus on maximizing water collection at the cost of efficiency because the feasibility of actively harvesting fog must be proved before trying to …

Increasing Isentropic Efficiency With Hydrostatic Head And Venturi Ejection In A Rankine Power Cycle, Nathan Daniel Ruiz

Master's Theses

This thesis describes the modifications made to the Cal Poly Thermal Science Laboratory’s steam turbine experiment. While the use of superheating or reheating is commonly used to increase efficiency in a Rankine cycle the methods prove unfeasible in a small scale project. For this reason, a mathematical model and proof of concept design using hydrostatic head generated by elevation and venturi ejection for use by the condenser is developed along with the equations needed to predict the changes to the system. These equations were used to create software to predict efficiency as well as lay down the foundation for future …

Effects Of Biomass Moisture Content On Volatile Flame Length During Cofiring With Coal, Matthew Pollard

McKelvey School of Engineering Graduate Student Theses & Dissertations

Cofiring biomass with coal can contribute to meeting Renewable Portfolio Standards (RPS) and reduce pollutant emissions. The physical characteristics and composition of biomass can vary significantly, which can affect the combustion characteristics. When cofiring biomass with coal, these differences can impact the structure of the volatile flame, the region where combustion of volatiles dominates. The length and location of the volatile flame is important to flame stability and determines the location and extent of volatile release. This has an effect on pollutant emissions, such as NOx (nitrogen oxides). Previously, the effects of parameters such as cofiring ratio, particle size, and …

Characterization Of Nano-Porous Si-Cu Composites To Enhance Lubricant Retention Impacting The Tribological Properties Of Sliding Surfaces, Julius Sheldon Morehead

Graduate Theses and Dissertations

As the expectations for modern machinery's tribological and thermal performances continue to rise, the retention of lubricant on the contact surfaces of their sliding components becomes an increasingly important issue. Friction and wear cause heat-related failures which lead to catastrophic damage to machinery. Evaporation of a lubricant's volatile constituents as well as lubricant migration leads not only to a reduction in lubricant quantity but also in its quality, thus facilitating component failures. In order to enhance component reliability, the surface should incorporate features that actively retain lubricants. The unique properties of nano-porous topographies such as their high surface area-to-volume ratio …

Development Of An Autonomous Single-Point Calibration For A Constant Voltage Hot-Wire Anemometer, Ryan Murphy

Master's Theses

Traditionally, the measurement of turbulence has been conducted using hot-wire anemometry. This thesis presents the implementation of a constant voltage hot-wire anemometer for use with the Boundary Layer Data System (BLDS). A hot-wire calibration apparatus has been developed that is capable of operation inside a vacuum chamber and flow speeds up to 50 m/s. Hot-wires operated with a constant-voltage anemometer (CVA) were calibrated at absolute static pressures down to 26 kPa. A thermal/electrical model for a hot-wire and the CVA circuit successfully predicted the measured CVA output voltage trend at reduced pressure environments; however, better results were obtained when the …