Mechanical Engineering Commons^™

Characterizing Energy Dissipation Of Shallow-Water Wave Breaking In A Storm Surge, Hunter Boswell, Guirong Grace Yan, Wouter Mostert

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

While understanding breaking waves is crucial for the development of parametrizations used in ocean wave modeling for both deep and shallow water, the complete process of wave breaking is not well understood. Here we present direct numerical simulations of two-dimensional solitary waves that shoal and break on a uniform beach in shallow water, with the presence of storm surge represented by an inshore region. The storm surge depth, beach slope, and wave amplitude are varied to study the dependence of energy dissipation in the breaker on wave and bathymetric parameters. We classify wave breaker types and find a separation between …

Lunar In-Situ Aluminum Production Through Molten Salt Electrolysis (Lisap-Mse), Jacob Ortega, Jeffrey D. Smith, Fateme Rezaei, David Bayless, William P. Schonberg, Daniel S. Stutts, Daoru Frank Han

NASA-Missouri Space Grant Consortium

The goal of Artemis is to establish a sustained presence on the Moon. To achieve so, numerous resources are necessary. The Moon contains several essential elements needed to sustain human presence. Most of those elements are trapped in the form of minerals. To refine those minerals into useful materials, reduction methods are needed. Most reduction methods on Earth require large amounts of mass and power which is unrealistic for early stages of building a lunar base. To solve this problem, we are developing a concept of Lunar In-Situ Aluminum Production through Molten Salt Electrolysis (LISAP-MSE).

The LISAP-MSE project, if successful, …

Quantitative Phase-Field Modeling Of Crack Propagation In Multi-Phase Materials, Arezoo Emdadi

Doctoral Dissertations

”Research presented in this dissertation is focused on developing and validating a computational framework for study of crack propagation in polycrystalline composite ceramics capable of designing micro-architectures of phases to improve fracture toughness and damage tolerance of ZrB₂-based ultra-high temperature ceramics (UHTCs). A quantitative phase-field model based on the regularized formulation of Griffith’s theory is presented for crack propagation in homogenous and heterogeneous brittle materials. This model utilizes correction parameters in the total free energy functional and mechanical equilibrium equation within the crack diffusive area to ensure that the maximum stress in front of the crack tip is …

Numerical Modeling Of Capillary-Driven Flow In Open Microchannels: An Implication Of Optimized Wicking Fabric Design, Mehrad Gholizadeh Ansari

Masters Theses

"The use of microfluidics to transfer fluids without applying any exterior energy source is a promising technology in different fields of science and engineering due to their compactness, simplicity and cost-effective design. In geotechnical engineering, to increase the soil's strength, hydrophilic wicking fibers as type of microfluidics have been employed to transport and drain water out of soil spontaneously by taking advantage of natural capillary force without using any pumps or other auxiliary devices. The objective of this study is to understand the scientific mechanisms of the capability for wicking fiber to drain both gravity and capillary water out of …

Behavior Of Eb Frp Masonry Bond Under Service Temperature, Zuhair Al-Aljaberi, John J. Myers, K. Chandrashekhara

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The interest in advanced composites in repairing and strengthening infrastructure systems has considerably increased, especially as the application externally bonded (EB) fiber reinforced polymer (FRP) has become more well established. Previous research on bond behavior has focused on impact of durability by considering exposure to harsh environmental conditions and testing the specimens after exposure, rather than testing bond performance during exposure. The influence of directly applying temperature on bond behavior represents an open topic that needs to be investigated in more detail. This study is one of the first studies to investigate the bond behavior when the composite is subjected …

The Effect Of On-Line Videos On Learner Outcomes In A Mechanics Of Materials Course, Jeffery S. Thomas, Richard H. Hall, Timothy A. Philpot, Douglas R. Carroll

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Mechanics of Materials course is one of the core engineering courses included in the curriculum of mechanical, civil, mining, petroleum, marine, aeronautical, and several other engineering disciplines. As a core course, the Mechanics of Materials course typically has large enrollment. Initiatives aimed at improving the effectiveness of the engineering core courses can have a major impact on engineering education by virtue of the large number of students affected.

Computers afford opportunities for creative instructional activities that are not possible in the traditional lecture-and-textbook class format. The study described in this paper examines the effectiveness of asynchronous online video that …

Residential Energy Performance Metrics, Christopher Wright, Stuart Werner Baur, Katie Grantham, Robert B. Stone, Scott Erwin Grasman

Engineering Management and Systems Engineering Faculty Research & Creative Works

Techniques for residential energy monitoring are an emerging field that is currently drawing significant attention. This paper is a description of the current efforts to monitor and compare the performance of three solar powered homes built at Missouri University of Science and Technology. The homes are outfitted with an array of sensors and a data logger system to measure and record electricity production, system energy use, internal home temperature and humidity, hot water production, and exterior ambient conditions the houses are experiencing. Data is being collected to measure the performance of the houses, compare to energy modeling programs, design and …

2nd Annual Undergraduate Research Conference Abstract Book, University Of Missouri--Rolla

Undergraduate Research Conference at Missouri S&T

No abstract provided.

Signal Mast Arm Fatigue Failure Investigation, Genda Chen, Michael G. Barker, Lokeswarappa R. Dharani, Christopher W. Ramsay

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Missouri Department of Transportation (MoDOT) has discovered and documented failures in several cantilever mast arms in the recent years. The failures were primarily by fatigue at the weld of the arm to the base plate attached to the mast. With over 6000 mast arms in service in Missouri, the failures raised concerns with the existing mast arm inventory and future mast arm design. This report presents findings from an effort to determine the cause of unexpected cracking in Missouri mast arms. Three causes of premature failure were investigated: the stress ranges experienced at the weld detail were higher than …

How To Establish Successful Cooperative Student Learning Centers For Stem Courses, Ronald James Bieniek, Douglas R. Carroll, Cesar Mendoza, Oran Allan Pringle, Ekkehard Sinn, Kai-Tak Wan, Donald C. Wunsch

Physics Faculty Research & Creative Works

Students learn more if they are actively involved in the learning process, particularly in a cooperative manner. Several UMR faculty have operated course-based learning centers (LCs) as part of the campus-wide Learning Enhancement Across Disciplines (LEAD) Program of student learning assistance and enhancement. LCs are designed to assist large numbers of students in a cost- and time-efficient manner that promotes student engagement without requiring undue amounts of faculty time. Course instructors spend time in the open learning environment of the LC, in lieu of office hours, guiding students to master course material and skills in their evolution from novice to …

Forensic Investigation Of Failed Mast Arms Of Traffic Signal Supported Structures, Genda Chen, Michael G. Barker, D. Scott Mackenzie, Christopher W. Ramsay, Joe Alderson, Lokeswarappa R. Dharani, Jiaqing Yu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In Missouri, 11 traffic signal mast arms fractured at the arm-post weld connection in 7 years. To reduce this fatigue failure, the Missouri Department of Transportation developed a fatigue-resistant weld profile that increases the weld leg and reduces the slope of the weld at the toe. This study investigated causes of the failed arms, compared performance of new and old weld profiles, and suggested retrofitting measures for further investigation. The scope included a metallurgical investigation of one failed field mast arm, laboratory fatigue testing of five prototype mast arms (two new and three old profiles), and laboratory failure analysis of …

Fatigue Assessment Of Traffic Signal Mast Arms Based On Field Test Data Under Natural Wind Gusts, Genda Chen, Jingning Wu, Jiaqing Yu, Lokeswarappa R. Dharani, Michael G. Barker

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In recent years, several states including Missouri, Wyoming, California, and Texas experienced fracture failures of traffic signal mast arms. Almost all the failures are associated with the propagation of defects or cracks. It is therefore imperative to evaluate existing mast arms using a simple yet accurate procedure. A statistical methodology is proposed to predict the fatigue life of signal mast arm structures on the basis of field-measured strain data. The annual occurrence of various stress levels is determined using the historical wind speed data in the vicinity of a mast arm structure and the strain readings of the structure under …

Optimal Design Rules Applied To The Design Of High-Speed Mechanisms Under Deflection And Stress Constraints, Frank W. Liou, Jenny Liu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Presented in this paper are two approaches for the design of flexible mechanisms under stress and deflection constraints. Based on the optimality conditions derived in this paper, two procedures are developed to design the minimum weight of mechanisms subject to stress and deflection limitations. The first procedure is the improvement of Thornton's design process r 17), and the second procedure is based on the interpolation technique. Several design examples are also presented to demonstrate these methods.

A Solar Energy System For Space Heating And Space Cooling, Thomas J. Mcnamara

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

To help reduce natural gas and electrical operating costs, a retrofit space heating and space cooling solar energy system is integrated into the existing conventional heating and air handling systems serving the exhibit spaces. This installation would not only provide substantial energy cost savings to the Museum, but it would also provide a means of showing and explaining the operation of an actual working solar energy system to the large number of daily visitors to the Museum. This report explains the design, operation and performance of this solar energy system.

Heat Recovery Devices For Building Hvac Systems, Ronald H. Howell, Harry J. Sauer Jr.

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

The opportunities and advantages of air-to-air heat recovery are described. The five basic types (rotary regenerative, coil loop run around, open run-around, heat pipe, and plate type) are described and their typical performance is presented. The potential savings in operating costs as well as initial equipment costs for common applications are presented.