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Small modular reactors (SMRs) are small-scale reactor designs (< 300 MWe), generally planned for deployment as multi-module nuclear power plants. Due to their small size, SMR modules could be manufactured in a factory and deployed to a site via truck or rail for installation and fueling. SMRs are being evaluated for their ability to provide both power and steam, such that they could be a viable replacement for fossil fuels. SMRs have been considered for coupling to manufacturing processes in addition to being connected to the grid, allowing them to follow the net grid demand in a “load following” operational mode during times of high renewable generation. Alternately, SMRs could be used to replace cogeneration and combined-cycle processes at manufacturing plants which utilize natural gas and other fossil fuels. Idaho National Laboratory (INL) is studying the use of SMRs for large-scale manufacturing processes that require both electricity and steam. The current study examines the integration of a SMR with two mid-size pulp and paper mills in the southeastern United States. The study consists of three parts: steady-state analysis of the mill, elimination of fossil fuel use in the lime kilns, and economic analysis of the modified plant operations. A steady-state model of each mill is developed in Aspen HYSIS based on real data from the operation of each mill. The steady-state model is then modified to include the SMR while maintaining production steam quality and making as few changes to existing equipment as possible. This model gives an estimate of the minimum requirements for SMR output, as well as the change in generation by existing boilers and turbines. With an overall picture of the new plant operation and determining the number of SMR modules required, further changes are suggested to minimize or completely eliminate fossil fuel use from the plant. Apart from steam generation, the largest consumer of fossil fuels at the plant is typically the lime kilns. Conversion of the lime kilns from fossil fuel combustion to electric heating is the most feasible solution to eliminate fossil fuels. This study finds that electric lime kilns are economical when the plant has a surplus This study presents a feasible example of using an SMR as a substitute for fossil fuel cogeneration. If this approach were expanded across the manufacturing industry, it would have a significant impact on environmental emissions and air quality.

The Master of Science in Engineering program at Milwaukee School of Engineering has had its share of curriculum changes based on feedback from various stakeholders and annual assessment of the program leading to continuous improvement. One of the student outcomes is to have demonstrated an ability to integrate and analyze information in a chosen specialty in the form of scholarly work, either as an independent specialty paper or as an independent engineering project. And another outcome that follows is to have the ability to effectively present and communicate technical concepts, both orally and in writing. Even with all the engineering skills developed through discipline-specific coursework, these two outcomes were still quite a challenge to numerous students. While the program director takes measures to connect students with the appropriate advisor and even assists in technical content, the program needed and implemented the constant presence of a non-technical person as a member of the committee to improve communication of students through all stages of proposal writing, progress report and final report. We had tried one class of technical writing as a separate entity for students to take before they embarked on a capstone project, but the effectiveness varied as the principles had to be personally applied by the graduate student for the individual project. With the new approach, the student’s resources have grown, the project path has been made seamless, the effectiveness of working on the technical content and report writing in tandem right from the literature search and proposal development has resulted. The historic development of the current approach, including an overview of program educational objectives and student outcomes, is presented. The paper also showcases the results in terms of publications by the students who have grown in confidence in writing skills. This paper aims at enabling informed discussion for engineering graduate programs across the United States seeking to aid their students in this critical area of communication.

Paper production is an energy intensive industry but due to the wastes of its process (black liquor, waste biomass, sludge) has the capacity to generate most of its energy internally. Central to this balance are cogeneration units that guarantee the internal production of heat and electricity. These are sized for the company’s thermal load, with excess electricity injected into the grid. The efficient use of endogenous resources is a major route for improving the energy and environmental efficiency of the plant. Some of the waste materials include biomass wastes, sludges and other industrial wastes such as plastics. The present work aims to identify the opportunity of introducing a waste biomass gasification plant and the use of the produced synthesis gas, replacing the natural gas currently used in the turbine included in the company’s cogeneration unit. In this scenario, one of the cogeneration units in its current configuration has two steam boilers (one biomass; one black liquor) and a gas turbine whose waste heat feeds a recovery boiler to produce steam. The work involved several steps: the energy balance of the unit, the characterization of biomass residues (mixing bark, pine bark, eucalyptus bark, and refuse fibers), the test experimental analysis of residual biomass gasification and the characterization of the synthesis gas produced. In the electric and thermal energy producing units, gas turbines have a working efficiency above 35% while the steam turbines is considerably lower (15%). The efficiency of the chemical recovery boiler (79.5%) is lower than that of the biomass boiler (89.5%). From the experimental analysis of biomass it was found that most of them have a carbon and hydrogen content higher than 48 % and 5 %, respectively. In terms of higher calorific value (HHV), for the biomass where it was possible to determine it, the value is between 19.3 and 23.6 MJ/kg. These properties reveal that the selected biomasses from within the company, have potential as fuels. The limitation on its use may be due to the ash content, which tends to exceed 10 %. A gasification test (90 % eucalyptus biomass and 10 % mixture biomass) was also carried out to produce syngas and further characterization. The calorific value of the gas produced was 18 MJ/kg, with an absolute density of 1.17 kg/m3. It can thus be seen that for a gas turbine with a 35.8 % efficiency with a workload of 29.9 MWe 4.6 kg/s of syngas is required.

This paper was removed at the author’s request on December 1, 2022. Copyright © 2022 by ASME

The potential development of automated grading brings us the opportunity to change the way of teaching. In this paper, we present our pilot study of the correlations between the scores of engineering assignments and several task-independent features. This work aims to identify features that can subsequently be used in a machine learning framework to support automated grading. We also identified some interesting patterns in this dataset. Our result shows that length features such as word count may indicate a highly structured assignment’s quality, and the number of grammar errors has the potential to be part of the evaluation if we use a carefully designed grammar checker. The present study is expected to contribute to our understanding of automated grading of mechanical engineering technical reports and provide insights into rubric design for assignments.

This paper was removed at the author’s request on December 1, 2022. Copyright © 2022 by ASME

The design and analysis of a paper-based microfluidic analytical device (μPAD) are presented in this paper for the detection of fentanyl and related synthetic opioids. Fentanyl, a synthetic opioid, is an extremely fast-acting synthetic narcotic analgesic having a high potency of approximately 100 to 200 times that of morphine. Detection of fentanyl can be done by colorimetric assays, i.e., spot tests with paper strips and μPADs which offer speed, simplicity of operation, portability, and affordability. The microfluidic behavior of liquid specimen and paper in the μPADs and test strips play a significant role in drug detection methods. Therefore, the study contains the fabrication of the test device using 3D printing and analysis of microfluidic behavior of the paper-based fentanyl test device. A multiphase computational fluid dynamics (CFD) model of a 3D microchannel is developed to evaluate the microfluidic properties. The CFD model incorporates the properties of cellulose and fentanyl solution to determine the flow parameters using the volume of fluid method. Wicking in the cellulose paper is studied analytically considering the Lucas-Washburn equation and Darcy’s law. Experiments with the fabricated μPAD and commercial test-kit samples are also conducted to compare the experimental results with the results for the flow parameters found from the numerical simulation.

Microfluidic paper-based analytical devices (μPADs) are cost-effective point-of-care diagnostic devices. μPADs consist of porous filter paper patterned with hydrophobic solid ink barriers to create flow channels. Because a liquid sample flows through the paper channel driven by capillary force, the resultant flow is usually slow. To overcome this limitation, a hollow channel can be added to a μPAD to increase the flow speed significantly. The liquid flow through the hollow channel is known to be driven by a pressure difference between the inlet and outlet of the device. Accordingly, theoretical models have been proposed to understand and predict flow characteristics of μPADs with hollow channels. The goal of this study is to experimentally characterize liquid flow through μPADs having a hollow channel, by investigating relationships among the travel distance of the liquid front through the μPADs, the applied pressure difference, and the dimension of the hollow channel. Thus, the outcome of this study would contribute to validating the theoretical models and enable better control of liquid sample flow in μPADs with hollow channels.

Due to depleting natural resources, it is necessary to develop eco-composite materials that are fabricated from sustainable and inexpensive materials such as recycled paper or cellulose-based materials. Such materials are required to meet the mechanical performance at par with traditional materials. The main aim of this study was to investigate the mechanical performance of a composite material fabricated from paper pulp and polyvinyl acetate (wood glue). It is expected that a high strength composite material may be achieved by varying the amount of paper-pulp fiber fraction from 7.5%, 10%, 20%, 30%, 40%, 50% to 60% weight. A tensile test was conducted and it was found that an increase in fiber content on the fabricated composite resulted in an increase in ultimate tensile strength and a decrease in corresponding strain. Furthermore, the material becomes more brittle at higher fiber content and conversely, more ductile at lower fiber content. The ultimate tensile strength was found to be 7.69 MPa at 60% w.t fiber and the minimum tensile strength was 0.12 MPa at 0% w.t fiber. There were no signs of fiber content limit observed in the obtained results. It was concluded that a composite of moderate strength was produced and future work is required in order to fully understand how the composite behaves at different loading conditions. However, an optimum fiber content limit will have to be determined.

Our niche method independently estimates hourly commuter rail station-to-station origin-destination (OD) matrix data each day from ticket sales and activation data from four sales channels (paper/mobile tickets, mail order, and onboard sales) by extending well-established transportation modelling methodologies. This algorithm’s features include: (1) handles multi-pack pay-per-ride fare instruments not requiring electronic validation, like ten-trip paper tickets “punched” onboard by railroad conductors; (2) correctly infers directionality for direction-agnostic ticket-types; (3) estimates unlimited ride ticket utilization patterns sufficiently precisely to inform vehicle assignment/scheduling; (4) provides integer outputs without allowing rounding to affect control totals nor introduce artifacts; (5) deals gracefully with cliff-edge changes in demand, like the COVID19 related lockdown; and (6) allocates hourly traffic to each train-start based on passenger choice. Our core idea is that the time of ticket usage is ultimately a function of the time of sale and ticket type, and mutual transformation is made via probability density functions (“patterns”) given sufficient distribution data. We generated pre-COVID daily OD matrices and will eventually extend this work to post-COVID inputs. Results were provided to operations planners using visual and tabular interfaces. These matrices represent data never previously available by any method; prior OD surveys required 100,000 respondents, and even then could neither provide daily nor hourly levels of detail, and could not monitor special event ridership nor specific seasonal travel such as summer Friday afternoons.

This paper was removed at the author’s request on October 22, 2021. Copyright © 2021 by ASME

This paper was erroneously published in ASME Turbo Expo 2021: Turbomachinery Technical Conference and Exposition, Vol. 2D and removed on October 13, 2021. Copyright © 2021 by ASME

Large potential exists in recovering waste heat from paper industry processes and machinery. If the overall energy efficiency would be increased, it could lead to significant fuel savings and greenhouse gas emission reduction. The organic Rankine cycle (ORC) system is a very strong candidate for converting low-grade waste heat into power. However, there is a lot of water vapor containing latent heat in the exhaust gases from the drying process in the paper industry. Thus, the aim of this research work is to increase the efficiency of the ORC system by recovering not only the sensible heat but also the latent heat from the exhaust gases in the paper drying process. In order to recover the latent heat from the moist exhaust gases, one idea of this article is to introduce a direct contact condensing unit into the ORC system. The performance of ORC system with the direct contact condensing unit was analyzed by using the CHEMCAD software. A case study was conducted based on data of the exhaust gases from a tissue production / drying machine. Latent heat will be recovered when the evaporating temperature of the ORC working fluid is lower than the dew point of the water vapor in the exhaust gases. The results showed that the available heat load was increased when the evaporating temperature was reduced. Furthermore, a performance comparison of the ORC systems with and without the direct contact condensing unit was carried out in the case study as well. The results showed that the ORC system with the direct contact condensing unit not only could recover latent heat from the water vapor in the exhaust gases but also could have a small size and small volume evaporator in the ORC system.

Fatigue limit state design check for offshore wind turbines is based on SN curves and the Palmgren–Miner rule approach and focuses normally on stationary processes for which startup and/or shutdown operations induced transient load processes are normally not accounted for. However, large databases of real-time measurements show that the shutdown and startup operations may appear in any operational conditions and the frequency of such operations could be considerable. Although design standards require fatigue design checks for the transient load processes induced by startup and shutdown operations, relevant publications addressing this issue are very limited in particular for floating wind turbines. This paper focuses on analyzing the importance of startup and shutdown induced transient load processes on fatigue damage in the tower of two MW-level horizontal axis semi-submersible wind turbines. The analysis is carried on by comparing short-term fatigue damage in several environmental conditions with and without the startup and shutdown induced transient load processes. It is found that, in many environmental conditions, startup and/or shutdown operations may make an increase in short-term fatigue damage by 10% to 100%, while in some situations, the fatigue damage may be increased by up to 200%. The importance of the transient load processes on long-term fatigue damage is related to the occurrence frequency of startup and shutdown events. Publicly available data indicate that the average time between two consecutive shutdown events might be less than 39 h. However, more data and analysis are needed regarding these issues.

The paper industry uses cylinder dryers that employ steam to heat the paper web moving over the cylinder outer walls. As steam condenses, the condensate is accumulated inside the cylinder dryers. The condensate is evacuated using either stationary or rotary siphons. The form of condensate motion occurring inside the cylinder can be puddling, cascading or rimming depending on the size of the cylinder dryer, the rotating speed, the amount of condensate, and the surface finish of the cylinder dryer inner wall with or without ribs or grooves. The behavior of the condensate inside the cylinder dryers affects the heat transfer through the cylinder wall, the torque and power requirements of the dryer, and the performance of the condensate evacuation via siphons. To help improve the drying performance, it is important to understand the fundamental thermal-fluid physics in the rotational dryer. Thus, the objectives of this study are (a) to investigate the dynamic two-phase flow and heat transfer behavior inside the rotational paper dryer at different rotational speeds; (b) to employ three different multiphase computational models, the Volume of Fluid (VOF) model, the Mixture model, and the Eulerian-Eulerian (E-E) model, and compare their results. The results show that the E-E model better captures the physics of condensate behavior inside the dryer. It also predicts very well the rimming speed in comparison with the empirical correlation although it takes longer computational time than the VOF model. The mixture model doesn’t adequately capture the cascade and rimming physics due to excessive liquid dispersion. Based on the results, the categorization of the thermal-flow behavior of the liquid layer is expanded from the traditional three phases to five phases: puddling, transitional cascading, cascading, transitional rimming, and steady rimming. A detailed analysis of the rotating liquid layer behavior and its corresponding wall heat transfer passing through each phase is presented. Generally, the heat transfer increases during the initial puddling period, followed by oscillatory attenuation during the cascade period, finally reaches steady state after rimming is achieved.

The modern methodology for quantifying the quality of experimental data is uncertainty analysis. This paper is a review of current methods with some examples primarily from naval hydrodynamics. The methods described are applicable to fluids engineering. The paper discusses the history of uncertainty analysis, US and international standards on uncertainty analysis, verification and validation standards for computational fluid dynamics, and instrument calibration. One important result is that random loading in force calibration can produce a lower uncertainty estimate than sequential loading.

A general method is proposed to predict the shape of a paper model of a brassiere cup. A brassiere cup consists of several cloth and wire parts and the shapes of cloth parts are determined by repeating creation of a paper cup model, check of its 3D shape, and modification of 2D shapes of parts. For efficient design of a brassiere cup, prediction of its 3D shape with a simulation is required. The deformed shape of a paper part is represented as a single or multiple developable surfaces. So, a model that can represent a part both as a single surface and as multiple surfaces is proposed. Which case is selected depends on the magnitude of the potential energy of the part in each case. The potential energy of the part and geometric constraints imposed on the part are formulated based on the model. Minimizing the potential energy under geometric constraints derives the stable shape of the part in either case. Furthermore, our proposed method can be applied to prediction of the paper cup model consisting of parts with complex shapes.

This paper was removed from publication at the author’s request, February 26, 2021. Copyright © 2021 by ASME

This paper was removed from publication at the author’s request, March 8, 2021. Copyright © 2021 by ASME

This paper was removed from publication at the author’s request. February 18, 2021. Copyright © 2021 by ASME