Mechanical Engineering Commons^™

An Experimental Thrust Measurement Study On The Nozzle Asymmetry Of Turbulent Pulsed Jets, Cesar Alberto Leos Jr.

Theses and Dissertations

The resurgence of pulsejet engines has renewed the interest of the flow characteristics responsible for the high levels of thrust augmentation that are necessary for Vertical/Short Take-Off and Landing (V/STOL) aircraft. It is well known that pulsation of the engine plays an important role on the thrust performance, but many of the characteristics that are primarily responsible for these enhancements are not well understood. This study is carried out to elucidate the effect of nozzle exit Mach number and the nozzle exit geometry on the characteristics of a high Reynolds number (~105), turbulent free pulsed jet.

Direct thrust measurements are …

Analysis Of Body And Tail Of A Flapping Drone, Yuan Chai

Student Works (2020-2029)

The Micro Aerial Vehicle (MAV) is a kind of unmanned aerial vehicle with a small size, which has a unique performance that larger aircrafts do not have. MAV can fly in confined spaces and perform hover, forward flight, etc. The flapping wing micro aerial vehicle is one type of flight imitates the insects (birds), which can fly based on the flapping wing. Compared with fixed-wing aircraft, the flapping wing micro aerial vehicle (FWMAV) has a smaller volume, lighter weight, and higher flight efficiency. FWMAV can be largely used in military and civil applications. In this project, the flapping drone is …

Fluid Flow Analysis Of Low-Altitute Agricultural Uav Pesticide Spraying Device, Dan Han

Student Works (2020-2029)

The nozzle is an important part of the drone pesticide spraying device. The quality of the nozzle directly affects the atomization performance. Fan nozzles are widely used in the field of plant protection in agriculture, forestry, pest control, and weed removal. When using drones to spray pesticides, the spraying velocity, the spraying range of the pesticides, and the atomized particle size are all key factors that directly affect the efficiency of pesticide use. This paper uses SOLIDWORKS and ANSYS software to design and simulate. The boundary conditions are kept the same, and the influence of the nozzle's grooving angle (α), …

Cfd Modelling Of Multiphase Flow In Static Mixer, Silverrajan Viknesvaran

Student Works (2020-2029)

Modelling of Multiphase flow through a Kenics static mixer were presented in this paper. Multiphase mixing is a challenging process in industries such as pharmaceutical, food and petroleum since two-different phases can be immiscible towards each other. Stirred tank mixing is the most common method used in industries. However, this type of method costs a lot in terms of energy and manpower specially when mixing immiscible liquids. Hence, The Kenics Static Mixer could be a good solution for multiphase mixing when its correctly configured and studied. Two phases used in this paper were aqueous solution: refined CMC as continuous phase …

Biomechanical Investigation Of Individual With Over-Pronation And Over-Supination Foot During Walking, Ghani Nur Saibah

Student Works (2020-2029)

Over-pronation and over-supination foot conditions are foot deformity that can lead to unstable ankle and subtalar joint during walking. They are define as condition where the foot roll in and out excessively from its neutral line and can lead to misalignment of the foot and leg in human in which can create abnormal gait cycle. Therefore, the purposes of this study are to analyze the foot-ankle joint biomechanical behavior including the range of motion, joint moment, joint power and GRF in a complete gait cycle for all subjects in this study and to compare the foot-ankle biomechanical behavior between normal …

Study Of Heat Transfer And Friction Loss Of Nanofluid Suspension Flow In Square Pipe Heat Exchanger, Krishnan Jayprasanth

Student Works (2020-2029)

An experimentational analysis was done to evaluate heat transfer features of graphene oxide (GO) nanofluid inside the cross section of square cross tube that was exposed to a uniform constant heat flux of the test segments. Lately huge figures of researches have been are proceeded out to examine the outcome of nanofluid in augmentation of the heat transfer rate in numerous heat exchangers particularly using hummer method to attain GO. In this case, advanced hummer method was used to obtain GO and further analyses the effect of the nanofluids. The viscosity and thermal conductivity for the (GO) nanofluids at the …

Kinetic Study Of In-Pipe Water Flow For Power Generation, Surendaran Venuthan

Student Works (2020-2029)

In-pipe turbine generator has a potential to harvest energy from an existing water flow from distribution pipe which have natural and pumping capacity. That flow will be used to convert kinetic energy from the pipe to rotate the turbine. In turn, the turbine may be connected to a generator to produce electric power. The fact that the in-pipe turbine generator will be a useful energy harvesting tool with potential with industrial application is recommended by many scholars. However, there is a concern where there are many types and sizes of pipe that is readily used in the water works industry. …

Microstructural Evolution And Mechanical Properties Of Ultra-Fine Grained Tubular Components Processed By Severe Plastic Deformation, Mesbah Mohsen

Student Works (2020-2029)

The lightweight alloys have been widely used in various engineering applications such as automotive, aerospace, construction, and biomedical industries due to their low densities, high ductility, formability, and facile machining. However, the emerging trend for materials with high mechanical strength and plasticity hampers the widespread application of these alloys. Over the last two decades, severe plastic deformation (SPD) has been introduced as a promising approach for enhancement of the mechanical performance of the lightweight alloys through microstructural manipulations and grain refinement. However, the SPD techniques have been extensively utilized for the fabrication of non-tubular geometries and the studies on the …

Cooking Systems Using Aluminum Foam, Ryan Tetsuo Mizukami

Physics

In developing countries, the use of wood burning fires for cooking is cause for illness and death. With this in mind, research was conducted to develop a solar cooking device capable of cooking of soup within 15 mins in order to reduce the negative impacts of cooking with wood. Current methods of solar-based cooking, such as solar concentrators and solar tube ovens, are impractical. A small solar panel is a cost-effective way to produce energy but will not produce enough power to cook within a reasonable amount of time. Even if it is assumed that all of the energy produced …

Formula Sae Monocoque Chassis Development, Kc Egger, Brian Ford, Kyle Nagao, Neal Sharma, Donovan Zusalim

Mechanical Engineering

Formula SAE is a collegiate competition hosted by SAE International with the primary goal being to design, manufacture, and race an open wheel race car. The Cal Poly Racing Formula SAE team strives for improvement every race season and has remained competitive as a result. The 2019-2020 management team determined that further research and development towards the chassis would yield the greatest performance benefit for future seasons, as the previous chassis platform limited packaging and mounting options for vehicle subsystems which interfaced with the chassis.

A redesign of the Cal Poly Racing Formula SAE team’s carbon fiber reinforced polymer monocoque …

Effects Of Process Parameter Variation On The Surface Roughness Of Polylactic Acid (Pla) Materials Using Design Of Experiments (Doe), C. Burke, A. Dalal, A. Abukhalaf, Rafiqul Noorani

Mechanical Engineering Faculty Works

3D Printing (3DP) is an additive manufacturing technology used to rapidly build parts that are designed using 3D modeling software. 3DP builds a part by adding one layer of the working material at a time until the process is complete. One main concern with 3D printed samples is the high levels of surface roughness, which can result in the rejection of parts by many precision manufacturing companies. The objective of this research is to use the Design of Experiment (DOE) to analyze which factors influence the surface roughness of the part built from a 3D printer. In this research, a …

Feasibility Study On Concentrated Solar Power Plants In Malaysia, De Jen Choy

Student Works (2020-2029)

The rapidly growing economy and population in Southeast Asia has elevated the need for affordable, secured, sustainable and environmentally friendly energy sources. One such energy source is solar energy which is a suitable energy source for most Southeast Asian countries which are within the Sun Belt region. This study performs a performance and financial analysis on concentrated solar power (CSP) technologies, specifically the solar power tower (SPT) in the Malaysian environment through the use of simulation software. The significance of the study lies in the fact that limited research has been done on CSP technologies in Malaysia and the study …

Analysis Of One Way Valve Mechanism For Wings Of A Flapping Drone, Xinchen Deng

Student Works (2020-2029)

The flapping drone is one type of MAVs which is defined as a miniature unmanned aerial vehicle that is inspired by flying birds and insects. Flapping wings can make a perfect combination of thrust and lift by flapping up and down with full usage of unsteady air. The flapping drone has the advantages of high maneuverability and a special lift generation mechanism. Compared with rotary-wing or fixed-wing MAV, it is smaller, lighter, and has higher flight performance. It can quickly change the flight direction and flight speed by control the flapping frequency and it is the only flight mode that …

Investigations Of Air-Water Multiphase Flow In Tubes: Computational Fluid Dynamics, Wei Hong Goo

Student Works (2020-2029)

Mixing is a very crucial process in many industries, such as food processing industry, minerals processing industry, petrochemicals and refining industry, pulp and paper industry, polymer industry, pharmaceuticals industry and many more. There are different types of mixing, such as liquid-gas mixing, liquid-liquid mixing, solid-liquid mixing and many more. The definition of multiphase flow is the simultaneous flow of materials with multiple thermodynamic phases. A lot of process industries require multiphase flows during operation. Bubbly flow is defined as the flow of liquids that contains dispersed gas bubbles. One of the main applications of multiphases flows and bubbly flows is …

Thermodynamic Analysis And Optimization Of Organic Rankine Cycles Using 1-Butylpyridinium Tetrafluoroborate As A Geothermal Fluid, Kazemi Shabnam

Student Works (2020-2029)

Organic Rankine cycle (ORC) is a promising technology for electricity generation by utilizing heat sources at low to moderate temperature that ranges between 80-350° C. In the present work, an ionic liquid (1-butylpyridinium tetrafluoroborate, C9H14NBF4), a known green chemical and non-volatile compound with good thermal and chemical stability, significant heat capacity, low vapor pressure and a wide liquid temperature range (25 to 459 °C), is utilized as a geothermal fluid. Simulation and optimization were conducted for a basic organic Rankine cycle (basic ORC), a regenerative organic Rankine cycle (RORC) and a two-stage evaporative organic Rankine cycle (TSORC) by maximizing exergy …

Mental Workload Investigation Among Employees In A Selected Oil And Gas Company, C. Moosom Christyne Surindai

Student Works (2020-2029)

In recent years, there has been a substantial amount of studies being conducted in mental workload and mental health but there is little research conducted in the Malaysian context especially in the oil and gas field. This gives rise to the need for researching the level of mental workload and mental health problems that will help the stakeholders to protect the wellbeing of their employees. This study aims to investigate the mental workload and level of depression, anxiety and stress scale of employees in a selected oil and gas company by using CarMen-Q and DASS-21 mental health assessment tools, finds …

Study Of Heat Transfer And Friction Loss Of Nanofluid Suspension Flow In Circular Pipe Heat Exchanger, Ramadas Sandru

Student Works (2020-2029)

This stated experiment focused on the study of convective heat transfer and friction loss in a circular flow passage for Graphene oxide-based nanofluids which are consist of Graphene Oxide/Distilled water with their different wt. % concentrations. These GO/DW based nanofluids where been prepared by using a facile two-step method, while the GO particles were synthesized by a modified hummer method. Four different (0.025, 0.05, 0.075, and 0.1 wt. %) were produced by dispersing graphene particles in distilled water under high probe sonication. The GO/DW based nanofluids flowing in a horizontal shell and tube heat exchanger counter flow under turbulent flow …

Comparison Of Pressure-Assist Silver Sintering To Tin Silver Solder Alloy As Die Attach Material In High Power Semiconductor, Tolentino Erik Nino

Student Works (2020-2029)

The research is focused on pressure-assisted silver sintering material that is compared to tin silver solder alloy paste as used in power electronics. Material characterization, electrical tests, and reliability tests were conducted in the experiment. After drying process, it was observed that the Ag sintering paste height was reduced to approximately 40 percent. Die attach shear test showed that the average reading is about from 200 to 600 grams which are already enough to hold the dice before proceeding to the pressure sintering process. X-ray revealed that the void percent for SnAg paste sample is about 1.5 percent while pressure-assist …

Optimization Of Bioethanol Production, Engine Performance And Exhaust Emissions From Manihot Glaziovii And Sweet Sorghum In A Spark Ignition Engine, Sebayang Abdi Hanra

Student Works (2020-2029)

The ever-increasing fossil fuel consumption over the years is attributable to economic and population growth, which in turn, increases greenhouse gas emissions. Bioethanol is one of the promising solutions to address the depletion of fossil fuels as well as environmental problems. Manihot glaziovii tubers and sweet sorghum grains are inedible feedstocks that can be used for bioethanol production. The carbohydrate content (70%) of these biomasses makes them suitable as feedstocks for bioethanol production. In this study, enzymatic hydrolysis (liquefaction and saccharification) was used to obtain the reduction of sugars. The enzymes α-amylase from Bacillus licheniformis Type XII-A and amyloglucosidase from …

Understanding The Laser Powder Bed Fusion Of Alsi10mg Alloy, Holden Hyer, Le Zhou, Sharon Park, Guilherme Gottsfritz, George Benson, Bjorn Tolentino, Brandon Mcwilliams, Kyu Cho, Yongho Sohn

Mechanical Engineering Faculty Research and Publications

We examine the microstructural characteristics of LPBF AlSi10Mg produced by using a wide range of LPBF processing parameters with independently varied laser power, hatch spacing, scan speed, slice thickness, and the normalized energy density. The lower energy density produced lack of fusion flaws from residual interparticle spacing, while the higher energy density produced spherical pores from trapped gas. The highest density (> 99%) samples were produced by using an energy density of 32 to 54 J/mm³. Within this energy density range, use of smaller slice thicknesses increased the processing window that would produce dense AlSi10Mg samples. A cellular …

Low-Cost Reaction Wheel Design For Cubesat Applications, Nicholas J. Bonafede Jr.

Master's Theses

As science instruments on CubeSats become more sensitive to the attitude of the spacecraft, better methods must be employed to provide the accuracy needed to complete the planned mission. While systems that provide the accuracy required are available commercially, these solutions are not cost-effective, do not allow the design to be tailored to a specific mission, and most importantly, do not give students hand-on experience with attitude control actuators. This thesis documents the design, modeling, and simulation of a low-cost, student-fabricated, reaction wheel system for use in 3U CubeSat satellites. The entire design process for the development of this reaction …

Minimising Induced Drag With Weight Distribution, Lift Distribution, Wingspan, And Wing-Structure Weight, Warren F. Phillips, Douglas F. Hunsaker, Jeffrey D. Taylor

Mechanical and Aerospace Engineering Student Publications and Presentations

Because the wing-structure weight required to support the critical wing section bending moments is a function of wingspan, net weight, weight distribution, and lift distribution, there exists an optimum wingspan and wing-structure weight for any fixed net weight, weight distribution, and lift distribution, which minimises the induced drag in steady level flight. Analytic solutions for the optimum wingspan and wing-structure weight are presented for rectangular wings with four different sets of design constraints. These design constraints are fixed lift distribution and net weight combined with 1) fixed maximum stress and wing loading, 2) fixed maximum deflection and wing loading, 3) …

Optimization Of Aileron Spanwise Size And Shape To Minimize Induced Drag In Roll With Correlating Adverse Yaw, Joshua R. Brincklow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Most modern aircraft make use of modifying the main wing in flight to begin a roll. In many cases, this is done with a discrete control surface known as an aileron. The lift, drag, and moments for the wing are affected in part by the location and size of the ailerons along the length of the wing. The lift, drag, and moments can be found using a lifting-line theory that considers the circulation in airflow from many small sections of the wing. To minimize the drag due to lift on the wing, the ailerons must be optimized for the best …

Thermo-Mechanical Modeling And The Application Of Coiled Polymer Actuators In Soft Robotics And Biomimetics, Robert Hunt

UNLV Theses, Dissertations, Professional Papers, and Capstones

Coiled polymer actuators (CPA) are a recently discovered smart material. Due to their large tensile stoke and power densities they are often used as actuators or artificial muscles. CPA’s are fabricated from a polymer fiber, typically nylon, mechanically twisted into a coil or coiled around a mandrel and annealed. When heated over the glass transition temperature they can contract, expand or exhibit torsional actuation, depending on the fabrication method and end conditions.

The fabrication and application of CPA is well documented and has made many innovations in the fields of smart materials, soft robotics and the likes. However, there is …

Multiphysics Finite Element Analysis Of In-Pile Sensors For Advanced Nuclear Reactors, Takoda Linn Bingham

Boise State University Theses and Dissertations

Nuclear reactors have large needs for in-pile sensors that are durable in high temperature, radioactive, and corrosive environments. With the use of multiphysics finite element analysis (FEA) researchers can speed up sensor prototyping. FEA also allows for a better fundamental understanding of sensors and enables sensor optimization. This research focuses on three types of in-pile sensors developed at Idaho National Laboratory: acoustic sensors, linear variable differential transformers (LVDT), and capacitance based strain gauges (CSG). Two acoustic sensors, magnetostrictive waveguides and piezoelectric surface acoustic wave (SAW) sensors were first modeled. These models showed the acoustic wave patterns and estimated the speed …

Pitched Baseballs And The Seam Shifted Wake, Andrew W. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An experiment was conducted to investigate the effect that seams have on the way a baseball moves through the air. An examination of the airflow around a baseball led to the understanding that when seams are in certain areas on the baseball's surface the airflow changes. A subsequent experiment was performed which showed that when these changes in airflow were on one side of the baseball more than the other, the ball moved away from the side with the seams. This movement is in a different direction than the movement direction caused by a ball's spin. These experiments were done …

Benchmarking Of A Mobile Phone Particle Image Velocimetry System, David Armijo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One of the most important tools in a fluid dynamics laboratory is a particle image velocimetry (PIV) system. This system can measure the speed of a fluid flow simply by taking high-speed images of the motion of the fluid, then applying PIV cross-correlation software to calculate speed from the resulting images. The mI-PIV project is in the process of designing a new method of performing PIV by putting the cross-correlation software on a mobile phone application, called mobile Instructional PIV (mI-PIV). This system is an innovative stepping stone in making PIV systems more widely available. It is designed to be …

Thermal Modeling And Analysis Of Roadway Embedded Wireless Power Transfer Modules, Arden N. Barnes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wireless charging of electric vehicles is a developing technology which potentially increases efficiency and safety. It also allows for charging vehicles while they are moving by having charging stations embedded in the roadway. Because roadways are thermally insulating, it is important to know how the heat from the charging stations will move through the roadway, which will allow further research into whether the heat will cause damage to the components in the station or to the roadway. This thesis studies the way the heat moves through concrete with wireless charging coils embedded in it. This is accomplished by measuring the …

Fluted Films Caused By Gravity Driven Water Drainage From Vertical Tubes, Matthew B. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When a stationary mass of water in a vertical tube is suddenly released, it creates a variety of artistic shapes and behaviors as it escapes the tube exit. As the descending water accelerates in the tube, friction along the tube wall slows the outer radius, resulting in a moving film entrained on the tube that trails the main body of water. When this film exits the tube, surface tension, gravity, and inertia interact to cause the film to create a wide variety of shapes, including jets, tubes, water bells, champagne glasses, and bubbles; rich forms that appear in other natural …

A Feature-Based Approach To Function Modeling And Reasoning For Thermal-Fluid Systems Engineering, Lakshmi Narasimhon Athinarayana Venkatanarasimhan

Theses and Dissertations

This research is focused on extending the language of function modeling by developing CAD-like features that are built using primitive functions. These features are reusable units of functions that represent the working principle of a system of higher level of abstraction than the ones of the primitive functions published in prior literature. This approach can be used to also establish an alternate concept/working principle that satisfies the same features, and thus enabling the integration of function models into previously established concept generation programs. It is expected that designers perceive concepts at different levels of abstractions. As a result, the feature-based …