Engineering Commons^™

Heat Transfer Characteristics Of Latent Heat Thermal Energy Storage, Kedar Prashant Shete

Doctoral Dissertations

Latent heat thermal energy storage (LHTES) systems can be used to reduce electric demand when used in conjunction with Combined Heat and Power Plants or HVAC(Heating, Ventilation, Refrigeration and Air-Conditioning), as they can regulate the demand and supply of thermal energy. They can also be used to integrate renewable energy sources with the grid. A design procedure and performance modeling is required for designing and using thermal energy storage systems effectively. We propose hypotheses about the performance of an LHTES device with different operating conditions and material properties, for devices that are governed by different modes of heat transfer. We …

Numerical Investigation Of Flow And Thermal Behavior In Channels With Pcm-Filled Thermal Energy Storage Columns For Potential Application In Photobioreactors, Sameed Akber

Electronic Thesis and Dissertation Repository

Microalgae has been identified as a potential source in the production of biofuel. Photobioreactors, which are used for microalgae production, normally experience temperature variations over the diurnal cycle due to changes in ambient conditions. The thermal regulation of photobioreactors to minimize temperature variations will result in a higher yield of microalgae, which are sensitive to such variations. The present research is aimed to investigate a novel approach to thermally regulate photobioreactors using phase change materials (PCM) where the latent heat of the material is exploited as the energy storage. The present research uses a numerical approach to study the flow …

The Influence Of Flow Mechanotransduction On Endothelial Cells In The Lymphatic Valve Sinus, Joshua Daniel Hall

Doctoral Dissertations

Fluid flow in the cardiovascular and lymphatic systems influences the phenotype of endothelial cells that line the interior to the vessel via mechanotransduction. Geometric features in a vessel such as curvature, bifurcation, and valves promote heterogeneous fluid flow profiles, inducing a heterogeneous endothelial phenotype within a vessel region. Certain flow conditions are associated with vascular dysfunction, and diseases such as atherosclerosis preferentially develop in areas of flow disturbance. Lymphatic vessels are highly analogous to blood vessels, although lymphatic flow characteristics and its effect on lymphatic endothelial cells (LECs) via mechanotransduction have been comparatively less examined. The most significant geometric features …

Experimental Investigation Of Flow And Thermal Behavior In Channels With Pcm-Filled Thermal Energy Storage Columns For Potential Application In Photobioreactors, Kira Toxopeus

Electronic Thesis and Dissertation Repository

Microalgae has been identified as a potential source for the production of biofuels and other bio-products. The growth of microalgae is sensitive to the temperature variations inside the photobioreactor. The present research investigated an innovative approach to thermally regulate photobioreactors by introducing passive thermal energy storage using phase change material (PCM). The research was specifically focused on a novel design to integrate thermal storage in the reactor channel in the form of offset columns containing PCM. Two column shapes were considered: circular and square. The first part of the study was focused on characterizing the influence of offset column shapes …

Design And Testing Of Experimental Langmuir Turbulence Facilities, Zongze Li

USF Tampa Graduate Theses and Dissertations

Langmuir Circulation is a common phenomenon driven by wind in oceans and lakes and was first studied by Langmuir in 1927. According to various ocean observations, this kind of phenomenon plays an important role in many phenomena such as the aggregation of bubbles, the distribution of plankton as well as the mixing of spilled oil and sediment in the ocean. To study this, an experimental facility has been developed in the lab which creates a small scale version of Langmuir Circulation.

This thesis is about the design and testing of this tank and surrounding aluminum frame, as well as the …

Go With The Flow, Scott Weinhardt, Priscilla Ng, Ben Rydberg, Ritika Makhijani

Mechanical Engineering

This Final Design Review (FDR) report outlines the Fuel System Flow Analysis senior project completed by the presenters listed. Included is research about Solar Turbines’ needs, and objectives for our project, our design decision process and final design, manufacturing, design verification report, final results, and suggestions moving forward with this experiment. The goal of the project is to identify stable pressure fields throughout the Solar Turbines fuel delivery system. Specifically, the optimal placement for taking measurements downstream of the main and pilot fuel control valves. The data is used to validate the accuracy of computational fluid dynamic (CFD) models that …

Experiment And Computational Analysis On Effect Of Plasma Actuation Incompressible Flow Around Tandem Cylinders, Emmanuel C. Gabriel-Ohanu

Honors Undergraduate Theses

The utilization of steady state flow of air over tandem circular cylinders has several applications in engineering systems. Incompressible flow over circular cylinders in tandem at different spacing with and without plasma actuation on the leading cylinder will be investigated in this paper to understand the effects of plasma actuation on flow properties and wake region of the two cylinders in cross flow. The principal focus of the research is on the use of experimental and computational methods to study and provide valid results, the research will analyze the wake region, the effect of Reynolds number and the longitudinal spacing …

A Novel Numerical Method To Analyze Laminar Flow In Serrated Plate-Fin Heat Exchanger Designs, Nabila Rubaiya

Theses and Dissertations

In the present research work, a simple numerical method has been explored to calculate the performance of serrated plate-fins. The numerical data of heat transfer and pressure drop performances have been compared with the available literature [6, 21], by means of calculating Chilton-Colburn j Factor and Fanning Friction Factor f, respectively. The numerical findings show good agreement with the experimental results from literature. Hence, the numerical analysis procedure proposed in this paper can be used to predict the performance of new designs of plate fins including different types of notched serrated fins. A detailed calculation and analysis of results have …

Two-Phase Flow Regime Map For Large Diameter Pipes And High-Velocity Flows, Matheus Sigaki Capovilla

LSU Master's Theses

Worst-case-discharge (WCD) calculations are a pre-requisite for any new well to be drilled in the Gulf of Mexico (GoM). Models that were mostly developed for production rates prediction are currently used to calculate the WCD rate. These models were mostly developed for pipe diameters and flow velocities much smaller than those expected during WCD events. Therefore, these models may be miscalculating WCD rates.

This study aims at analyzing one of possible sources of errors in these models: the flow regime maps. The influence of diameter change on flow regimes is discussed. A thorough literature review is carried out for different …

Application Of Trained Pod-Rbf To Interpolation In Heat Transfer And Fluid Mechanics, Rebecca A. Ashley

Honors Undergraduate Theses

To accurately model or predict future operating conditions of a system in engineering or applied mechanics, it is necessary to understand its fundamental principles. These may be the material parameters, defining dimensional characteristics, or the boundary conditions. However, there are instances when there is little to no prior knowledge of the system properties or conditions, and consequently, the problem cannot be modeled accurately. It is therefore critical to define a method that can identify the desired characteristics of the current system without accumulating extensive computation time. This thesis formulates an inverse approach using proper orthogonal decomposition (POD) with an accompanying …

Development, Analysis, And Optimization Of A Swirl-Promoting Mean Flow Solution For Solid Rocket Motors, Andrew Steven Fist

Masters Theses

This work demonstrates and analyses a new flow candidate for describing the internal gaseous motion in simulated rocket motors. The fundamental features of this solution include the conservation of key system properties also incorporated in the classic Taylor-Culick (TC) system (i.e. inviscid, axisymmetric, steady and rotational properties), while allowing for the development of a swirling velocity component. The work compares the new solution to the development and formulation of the classic TC system, ultimately identifying that both the new and classic solutions are special cases of the Bragg-Hawthorne equation. Following this development, the text then explores the development of energy-optimized …

Segregation Of Particles Of Variable Size And Density In Falling Suspension Droplets, Melissa Kathleen Faletra

Graduate College Dissertations and Theses

The problem of the falling under gravity suspension droplet was examined for cases where the droplet contains particles with different densities and different sizes. Cases examined include droplets composed of uniform-size particles with two different densities, of uniform-density particles of two different sizes, and of a distribution of particles of different densities. The study was conducted using both simulations based on Oseenlet particle interactions and laboratory experiments. It is observed that when the particles in the suspension droplet have different sizes and densities, an interesting segregation phenomenon occurs in which lighter/smaller particles are transported downward with the droplet and preferentially …

A Study On Small Scale Intermittency Using Direct Numerical Simulation Of Turbulence, Saba Almalkie

Open Access Dissertations

Theory of turbulence at small scales plays a fundamental role in modeling turbulence and in retrieving information from physical measurements of turbulent flows. A systematic methodology based on direct numerical simulations of turbulent flows is developed to investigate universality of small scale turbulence. Understanding characteristics of the small scale intermittency in turbulent flows and the accuracy of the models, measurements, and theories in predicting it are the main objectives. The research is designed to address two central questions; 1) possible effects of large scale anisotropies on the small scale turbulence and 2) potential biases in characterizing small scale turbulence due …

Port Flow Test System, Daniel Chairez, Chelsea E. Crawford, Daniel S. Welch

Mechanical Engineering

Solar Turbines Gas Compressor Engineering Division of San Diego, California called upon the Mechanical Engineering students of California Polytechnic University, San Luis Obispo to provide recommendations for optimization of compressor end cap port design. Various sizes of compressors have end caps with numerous ports that exchange fluids between the inside and outside of the working fluid pressure vessel. Because so many ports must exist on the end caps, unusual flow paths are created to supply the appropriate location within the compressor. These flow paths commonly consist of a drilled inlet hole which intersects with a sudden expansion. The sudden expansion …

Modeling Of Thermal Non-Equilibrium In Superheated Injector Flows, Shivasubramanian Gopalakrishnan

Open Access Dissertations

Among the many factors that effect the atomization of a fuel spray in a com- bustion chamber, the flow characteristics of the fuel inside the injector nozzle play significant roles. The enthalpy of the entering fuel can be elevated such that it is higher than the local or downstream saturation enthalpy, which will result in the flash-boiling of the liquid. The phase change process dramatically effects the flow rate and has the potential to cause subsonic two-phase choking. The timescale over which this occurs is comparable to the flow-through time of the nozzle and hence any attempt to model this …

Me 347 Fluid Mechanics Lab Experiments, 7th Edition

Mechanical Engineering Lab Manuals

Welcome to the documentation used to describe and conduct ten fluid mechanics experiments that are located in the Fluid Mechanics Laboratory in Building 192, Room 102, at Cal Poly State University. All of the experiments are designed to illustrate many of the concepts presented in undergraduate fluid mechanics classes. The first objective of each lab is to give students hands-on experience with fluid mechanics experiments. This includes working with standard facilities and instrumentation found in fluid mechanics laboratories. The second objective of each lab is to learn how to use experimentally collected data to either validate an analytical model for …