Open Access. Powered by Scholars. Published by Universities.®

Mechanical Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 17011 - 17040 of 30252

Full-Text Articles in Mechanical Engineering

Host-Guest Interaction Dictated Selective Adsorption And Fluorescence Quenching Of A Luminescent Lightweight Metal-Organic Framework Toward Liquid Explosives, Dan Liu, Xiaojuan Liu, Yongxin Liu, Yang Yu, Fanglin Chen, Cheng Wang Oct 2014

Host-Guest Interaction Dictated Selective Adsorption And Fluorescence Quenching Of A Luminescent Lightweight Metal-Organic Framework Toward Liquid Explosives, Dan Liu, Xiaojuan Liu, Yongxin Liu, Yang Yu, Fanglin Chen, Cheng Wang

Faculty Publications

In this article, we report the successful preparation of a Mg-based luminescent MIL-53 metal–organic framework (MOF), namely [Mg2(BDC)2(BPNO)]·2DMF (1) (BDC = 1,4-benzene dicarboxylate, BPNO = 4,4’- dipyridyl-N,N’-dioxide, DMF = N,N-dimethylformamide) in a mixed solvent containing a 2 : 3 volume ratio of DMF and ethanol (EtOH) under solvothermal conditions. Desolvated compound 1a can be used as an absorbent for selective adsorption and separation of liquid explosives, including nitroaromatic (nitrobenzene (NB)) and nitroaliphatic (nitromethane (NM) and nitroethane (NE)) compounds, through single crystal-to-single crystal (SC–SC) transformations. As one of the weakly luminescent MOFs, the luminescence of compound 1a could be quenched by …


Novel Quantitative Macro Biomolecule Analysis Based On A Micro Coulter Counter, Y Han, H. Wu, F. Liu, Gang Cheng, Jiang Zhe Oct 2014

Novel Quantitative Macro Biomolecule Analysis Based On A Micro Coulter Counter, Y Han, H. Wu, F. Liu, Gang Cheng, Jiang Zhe

Mechanical Engineering Faculty Research

We demonstrate quantitative biomolecule analysis using a micro coulter counter. Specific binding between antibody functionalized microparticles and target biomolecule cause large aggregates of microparticles. The micro coulter counter was employed to measure aggregation ratio, ratio of the aggregate counts to the total particle counts. Goat anti-rabbit IgG, used as a model biomarker, were tested in this paper. The experiment results showed that the aggregation ratio increases with the increasing biomolecule concentration, and the detectable concentration range from 16 to 160 ng/ml was achieved.


Passive Continuous Particle Focusing In A Microchannel With Symmetric Sharp Corner Structures, Liang-Liang Fan, Liang Zhao, Xu-Kun He, Hand Yu, Qing-Yu Wei, Jiang Zhe Oct 2014

Passive Continuous Particle Focusing In A Microchannel With Symmetric Sharp Corner Structures, Liang-Liang Fan, Liang Zhao, Xu-Kun He, Hand Yu, Qing-Yu Wei, Jiang Zhe

Mechanical Engineering Faculty Research

We report a continuous passive particle focusing method using a novel microchannel with symmetric sharp corners which induce curved streamlines and large centrifugal force on particles. At appropriate flow rate, the centrifugal force generated on particles exceeds the inertial lift force; particles driven by the centrifugal force migrate toward the center of the microchannel, achieving continuous particle focus-ing. With simple structure and operation, this method can be potentially used in particle focusing and ex-traction processes in a variety of lab-on-a chip applications.


A New Microfluidic Device For Complete, Continuous Separation Of Microparticles, Liang-Liang Fan, Xu-Kun He, Yu Han, Li Du, Liang Zhao, Jiang Zhe Oct 2014

A New Microfluidic Device For Complete, Continuous Separation Of Microparticles, Liang-Liang Fan, Xu-Kun He, Yu Han, Li Du, Liang Zhao, Jiang Zhe

Mechanical Engineering Faculty Research

A microchannel with symmetric sharp corners is reported for particle separation, based on the inter-play between the inertial lift force and the centrifugal force induced by sharp corners. At an appropriate flow rate, the centrifugal force is larger than the inertial lift force on large particles, while the inertial lift force is dominant on small particles. Hence large particles are centrifuged to the center, while small par-ticles are focused at side streams, achieving complete particle separation. The device requires no sheath flow, avoiding the dilution of analyte sample and complex operation, and can be potentially used for many lab-on-a-chip applications.


Recent Advances In The Field Of Bionanotechnology: An Insight Into Optoelectric Bacteriorhodopsin, Quantum Dots, And Noble Metal Nanoclusters, Christopher Knoblauch, Mark Griep, Craig Friedrich Oct 2014

Recent Advances In The Field Of Bionanotechnology: An Insight Into Optoelectric Bacteriorhodopsin, Quantum Dots, And Noble Metal Nanoclusters, Christopher Knoblauch, Mark Griep, Craig Friedrich

Michigan Tech Publications, Part 1

Molecular sensors and molecular electronics are a major component of a recent research area known as bionanotechnology, which merges biology with nanotechnology. This new class of biosensors and bioelectronics has been a subject of intense research over the past decade and has found application in a wide variety of fields. The unique characteristics of these biomolecular transduction systems has been utilized in applications ranging from solar cells and single-electron transistors (SETs) to fluorescent sensors capable of sensitive and selective detection of a wide variety of targets, both organic and inorganic. This review will discuss three major systems in the area …


Flame Behavior Of Bifurcated Jets In A V-Shaped Bluff-Body Burner, Hsiu Feng Yang, Ching Min Hsu, Rong Fung Huang Oct 2014

Flame Behavior Of Bifurcated Jets In A V-Shaped Bluff-Body Burner, Hsiu Feng Yang, Ching Min Hsu, Rong Fung Huang

Journal of Marine Science and Technology–Taiwan

A plane fuel jet bifurcated into two streams of jets by a V-shaped bluff-body burner with co-flowing air streams was studied. The flame behavior, length, and temperature distributions of the bifurcated jets were experimentally examined. Flame behavior was characterized by flame visualization and instantaneous photograph. The flame length characteristics was obtained by using the long-exposure flame images. The temperatures distributions were measured by using a finewire thermocouple. Three characteristic flame modes were revealed—attached flame, transitional flame, and lifted flame. The flame length and width of the bifurcated jets increase with the increase of the Rec in fixed Rea. The length …


Assessing Fishing Port Locations For Adaption Into Yacht Marinas In Taiwan, Ching-Min Yang, Chi-Chang Lai1, Long-Jing Wu, Jan-Jung Li Oct 2014

Assessing Fishing Port Locations For Adaption Into Yacht Marinas In Taiwan, Ching-Min Yang, Chi-Chang Lai1, Long-Jing Wu, Jan-Jung Li

Journal of Marine Science and Technology–Taiwan

As fishing resources gradually disappear, the original functions of fishing ports change. Modernizing traditional fishing ports is valuable for the fishing industry, tourism, and waterfront development. To determine suitable locations for such ports, an analytic hierarchy process and an interview survey were used to objectively analyze inputs from fishing port managers and yacht users. To establish additional yacht marinas in fishing ports, both groups attached importance to the “support of government and integration of policies” (rank and additive weight of manager : user = 1[0.185] : 2[0.119]). Therefore, inclusion of a complete and appropriate management mechanism must be emphasized during …


Offshore Structural Dynamic Analysis Considering Soil-Structure Interaction By A Coupled Bem And Meshfree Method, Min-Chou Tsai, Hsien Hua Lee, Tinh Quoc Bui, Chuanzeng Zhang Oct 2014

Offshore Structural Dynamic Analysis Considering Soil-Structure Interaction By A Coupled Bem And Meshfree Method, Min-Chou Tsai, Hsien Hua Lee, Tinh Quoc Bui, Chuanzeng Zhang

Journal of Marine Science and Technology–Taiwan

An investigation of dynamic offshore structure considering soil-structure interaction by a coupled approach based on boundary element and meshfree methods is presented. The moving Kriging interpolation is used for generating the shape functions because of possessing the Kronecker delta property, which makes easier in imposing the essential boundary conditions. The governing elastodynamic equations are transformed into a standard weak formulation. It is then discretized into a meshfree system of time-dependent equations, which are solved by the standard implicit Newmark time integration scheme. Numerical examples illustrating the applicability and effectiveness of the proposed method are presented and discussed in details. A …


Fabrication And Characterization Of Silver- And Copper-Coated Nylon 6 Forcespun Nanofibers By Thermal Evaporation, Dorina M. Mihut, Karen Lozano, Heinrich D. Foltz Oct 2014

Fabrication And Characterization Of Silver- And Copper-Coated Nylon 6 Forcespun Nanofibers By Thermal Evaporation, Dorina M. Mihut, Karen Lozano, Heinrich D. Foltz

Mechanical Engineering Faculty Publications

Silver and copper nanoparticles were deposited as thin films onto substrates consisting of Nylon 6 nanofibers manufactured using forcespinningR equipment. Different rotational speeds were used to obtain continuous nanofibers of various diameters arranged as nonwoven mats. The Nylon 6 nanofibers were collected as successive layers on frames, and a high-vacuum thermal evaporation method was used to deposit the silver and copper thin films on the nanofibers. The structures were investigated using scanning electron microscopy–scanning transmission electron microscopy, atomic force microscopy, x-ray diffraction, and electrical resistance measurements. The results indicate that evaporated silver and copper nanoparticles were successfully deposited on Nylon …


Simulations Of Diffusion Driven Phase Evolution In Heterogenous Solids, Subramanya Gautam Sadasiva Oct 2014

Simulations Of Diffusion Driven Phase Evolution In Heterogenous Solids, Subramanya Gautam Sadasiva

Open Access Dissertations

With reduction in size, ever greater operational demands are placed on electronics components at all levels of the device, starting from the transistor level to the level of the package and the solder interconnects. Concurrently, there has been a move to more complicated materials systems in order to meet health and environmental guidelines. These trends of reducing size, increasing loads have increased the necessity to understand the mechanisms of the failure. ^ As the length scales are reduced, it becomes increasingly important to consider interfacial and micro-structural effects that can be safely ignored at larger length scales owing to the …


Studies Of Systems With Nonholonomic Constraints: The Segway And The Chaplygin Sleigh, Joseph Troy Lee Tuttle Oct 2014

Studies Of Systems With Nonholonomic Constraints: The Segway And The Chaplygin Sleigh, Joseph Troy Lee Tuttle

Open Access Theses

In this thesis, two systems with nonholonomic systems are investigated: the Segway and the Chaplygin sleigh. Using Lagrangian mechanics, the constrained nonlinear equations of motion for both systems are derived. By use of the nullspace of the constraint matrices, the unconstrained equations of motion can be obtained. For the Segway, these equations are linearized about a zero equilibrium state, placed into state space form and decoupled. A feedback controller is designed about the velocity and heading angle rate reference commands. To compare to the real data from the built Segway, measurement noise was also included in the model. Experimental data …


Piston / Cylinder Interface Of Axial Piston Machines – Effect Of Piston Micro-Surface Shaping, Ashley M. Wondergem Oct 2014

Piston / Cylinder Interface Of Axial Piston Machines – Effect Of Piston Micro-Surface Shaping, Ashley M. Wondergem

Open Access Theses

Axial piston machines are widely used in current industries such as aerospace, agriculture, automotive, heavy machinery, military, etc. Thus new cost-effective and highly efficient designs with better performance and reliability are needed. These new, high efficient pumps and motors will also aid in new applications such as hybrid hydrostatic transmissions and displacement controlled actuation. The aim of this work is to study how to reduce the energy dissipation (increase efficiency) while also improving the load carrying ability of the fluid film between the piston and the cylinder through surface shaping of the piston over a wide range of operating conditions. …


Indoor Acoustic Mapping And Geolocation, Thomas Shyy Oct 2014

Indoor Acoustic Mapping And Geolocation, Thomas Shyy

Open Access Theses

The Global Positioning System (GPS) is widely used in navigations of flights, vehicles and travelers nowadays. However, the signals are not always available and there are some cases where the receptions of the GPS signal can be lost because of the presence of urban canyons, buildings, tunnels and forests. Another down side for the GPS is that indoor positioning can be really difficult because of the greater signal interference from the indoor.

On the other hand, the concept of echolocation has also been used for positioning purposes. Echolocation offers a promising approach to improve the quality of life of people …


Thermal Efficiency And Emission Analysis Of Advanced Thermodynamic Strategies In A Multi-Cylinder Diesel Engine Utilizing Valve-Train Flexibility, Chuan Ding Oct 2014

Thermal Efficiency And Emission Analysis Of Advanced Thermodynamic Strategies In A Multi-Cylinder Diesel Engine Utilizing Valve-Train Flexibility, Chuan Ding

Open Access Dissertations

Stringent emission regulations and a growing demand for fossil fuel drive the development of new technologies for internal combustion engines. Diesel engines are thermally efficient but require complex aftertreatment systems to reduce tailpipe emissions of unburned hydrocarbons (UHC), particulate matter (PM), and nitrogen oxides (NOx). These challenges require research into advanced thermodynamic strategies to improve thermal efficiency, control emission formation and manage exhaust temperature for downstream aftertreatment. The optimal performance for different on-road conditions is analyzed using a fully flexible valve-train on a modern diesel engine. The experimental investigation focuses on thermal management during idling and high-way cruise conditions. In …


A Computational Analysis Of The Aerodynamic And Aeromechanical Behavior Of The Purdue Multistage Compressor, David Monk Oct 2014

A Computational Analysis Of The Aerodynamic And Aeromechanical Behavior Of The Purdue Multistage Compressor, David Monk

Open Access Theses

Compressor design programs are becoming more reliant on computational tools to predict and optimize aerodynamic and aeromechanical behavior within a compressor. Recent trends in compressor development continue to push for more efficient, lighter weight, and higher performance machines. To meet these demands, designers must better understand the complex nature of the inherently unsteady flow physics inside of a compressor. As physical testing can be costly and time prohibitive, CFD and other computational tools have become the workhorse during design programs.

The objectives of this research were to investigate the aerodynamic and aeromechanical behavior of the Purdue multistage compressor, as well …


Optical Properties Of Silicon Core/Multi-Shell Nanowires Using Fdtd And Ema Methods, Tae Kon Kim Oct 2014

Optical Properties Of Silicon Core/Multi-Shell Nanowires Using Fdtd And Ema Methods, Tae Kon Kim

Open Access Theses

Semiconductor nanowires are attracting intense interest as a promising material for solar energy conversion for the new-generation photovoltaic (PV) technology. In particular, silicon core/multi-shell nanowires (SiNWs) are under active investigation for PV and solar water splitting applications because they offer novel approaches for solar to electric energy or fuel conversion leading to high efficiency devices. ^ Theoretical studies using the finite-different time-domain method have been performed to investigate the optical properties of many nanostructure arrays, however, they are computationally intensive and require periodic condition, which may not be satisfied with most fabricated samples. In the present study, effective medium approximation …


Modeling Of High Pressure Radial Piston Pumps, Pulkit Agarwal Oct 2014

Modeling Of High Pressure Radial Piston Pumps, Pulkit Agarwal

Open Access Theses

Agarwal, Pulkit. M.S.M.E., Purdue University, December 2014. Modeling of High Pressure Radial Piston Pumps. Major Professor: Andrea Vacca, School of Mechanical Engineering A comprehensive multi-domain simulation tool for investigating the operation of radial piston machines has been developed in the present study. The simulation tool is capable of analyzing the displacing action of the machine parts as well as the power losses occurring in the lubricating interfaces which makes it useful for supporting the design process of radial piston units. The reference machine analyzed in this study is a radial piston pump of rotating cam type design used for high …


Dropwise Condensation Dynamics In Humid Air, Julian Eduardo Castillo Chaco Oct 2014

Dropwise Condensation Dynamics In Humid Air, Julian Eduardo Castillo Chaco

Open Access Theses

Dropwise condensation of atmospheric water vapor is important in multiple practical engineering applications. The roles of environmental factors and surface morphology/chemistry on the condensation dynamics need to be better understood to enable efficient water-harvesting, dehumidication, and other psychrometric processes. Systems and surfaces that promote faster condensation rates and self-shedding of condensate droplets could lead to improved mass transfer rates and higher water yields in harvesting applications. The thesis presents the design and construction of an experimental facility that allows visualization of the condensation process as a function of relative humidity. Dropwise condensation experiments are performed on a vertically oriented, hydrophobic …


Effects Of Hip And Ankle Moments On Running Stability: Simulation Of A Simplified Model, Rubin C. Cholera Oct 2014

Effects Of Hip And Ankle Moments On Running Stability: Simulation Of A Simplified Model, Rubin C. Cholera

Open Access Theses

In human running, the ankle, knee, and hip moments are known to play different roles to influence the dynamics of locomotion. A recent study of hip moments and several hip-based legged robots have revealed that hip actuation can significantly improve the stability of locomotion, whether controlled or uncontrolled. Ankle moments are expected to also significantly affect running stability, but in a different way than hip moments. Here we seek to advance the current theory of dynamic running and associated legged robots by determining how simple open-loop ankle moments could affect running stability. We simulate a dynamical model, and compare it …


High Voltage Rear Electric Drivetrain Design For A Parallelthrough-The-Road Plug-In Hybrid Electric Vehicle, Adam Garrett Fogarty Oct 2014

High Voltage Rear Electric Drivetrain Design For A Parallelthrough-The-Road Plug-In Hybrid Electric Vehicle, Adam Garrett Fogarty

Open Access Theses

Purdue University was selected as one of 15 universities to participate in a three year Advanced Vehicle Technology Competition (AVTC) called EcoCar2: Plugging Into the Future. The vehicle built by the Purdue team was a Parallel-Through-The-Road Plug-in Hybrid Electric Vehicle (PTTR PHEV). The vehicle utilized a B20 diesel powertrain to power the front wheels, as well as a custom electric drivetrain to power the rear wheels. Using this vehicle during the final year of the competition, the team was successful in placing 4th overall as well as 2nd in the category of Well-To-Wheel (WTW) Greenhouse Gas Emissions. A stock 2013 …


Design And Analysis Of A Cable-Driven Test Apparatus For Flapping-Flight Research, Stephen J. Musick Oct 2014

Design And Analysis Of A Cable-Driven Test Apparatus For Flapping-Flight Research, Stephen J. Musick

Open Access Theses

The biology, physiology, kinematics, and aerodynamics of insect flight have been a longstanding fascination for biologists and engineers. The former three are easily obtained through the observation of the organic species. The latter though, is very difficult to study in this fashion. In many cases, aerodynamic forces and fluid-body interactions can be simulated with computational fluid dynamics; another option is to use dynamically-scaled, experimental set-ups to measure physically these values.

An archetypal, experimental set-up may include one or two scaled wings, where each wing is actuated to achieve upwards of three degrees of freedom. The three degrees of freedom correspond …


Algorithm Development And Analysis For Advanced Enginetechnologies Including Piezoelectric Fuel Injection And Variablevalve Actuation, Bradley W. Pietrzak Oct 2014

Algorithm Development And Analysis For Advanced Enginetechnologies Including Piezoelectric Fuel Injection And Variablevalve Actuation, Bradley W. Pietrzak

Open Access Theses

As vehicle emissions standards and fuel economy constraints become increasingly strict, the automotive industry must employ the use of advanced engine technologies to overcome these challenges. Fuel injection rate shaping and cylinder deactivation (CDA) are two such technologies, and both of them require the design and implementation of algorithms using various hardware and software tools.

Fuel injection rate shaping is one path towards cleaner and more efficient diesel engines. Piezoelectrically-actuated fuel injectors are well-suited for rate shaping operation, but are difficult to control. Control-related challenges arise primarily due to the lack of measurements available in a fuel injection system on-engine, …


Analysis Of The Impact Of Early Exhaust Valve Opening And Cylinder Deactivation On Aftertreatment Thermal Management And Efficiency For Compression Ignition Engines, Leighton Edward Roberts Oct 2014

Analysis Of The Impact Of Early Exhaust Valve Opening And Cylinder Deactivation On Aftertreatment Thermal Management And Efficiency For Compression Ignition Engines, Leighton Edward Roberts

Open Access Theses

In order to meet strict emissions regulations, engine manufacturers have implemented aftertreatment technologies which reduce the tailpipe emissions from diesel engines. The effectiveness of most of these systems is limited when exhaust temperatures are low (usually below 200°C to 250°C). This is a problem for extended low load operation, such as idling and during cold start. Use of variable valve actuation, including early exhaust valve opening (EEVO) and cylinder deactivation (CDA), has been proposed as a means to elevate exhaust temperatures. This thesis discusses a research effort focused on EEVO and CDA as potential enablers of exhaust gas temperature increase …


Development Of Sound Quality Metrics For Gear Rattle In Diesel Engines, Brandon Sobecki Oct 2014

Development Of Sound Quality Metrics For Gear Rattle In Diesel Engines, Brandon Sobecki

Open Access Theses

Sound quality is an important factor in the design of competitive diesel engines. The noise produced by specific components and mechanisms in the engine can play a significant role in determining the perceived quality of the overall noise and in turn the perceived quality of the engine. The goal of the present research is to characterize the sounds produced by the phenomenon known as gear rattle and to develop a model that can be used to assess gear rattle levels in a way that connects directly with human perception of rattle. Most previous work in this area has been focused …


Measurement Of The Responses Of Polyurethane And Confortm Foams And The Development Of A System Identification Technique To Estimate Polyurethane Foam Parameters From Experimental Impulse Responses, Vaidyanadan Sundaram Oct 2014

Measurement Of The Responses Of Polyurethane And Confortm Foams And The Development Of A System Identification Technique To Estimate Polyurethane Foam Parameters From Experimental Impulse Responses, Vaidyanadan Sundaram

Open Access Theses

Flexible polyurethane foam is the main cushioning element used in car seats. Optimization of an occupied seat's static and dynamic behavior requires models of foam that are accurate over a wide range of excitation and pre-compression conditions. Experiments were conducted to measure the response of foam over a wide range of excitation which include slowly varying uniaxial compression tests on a 3 inch cube foam sample, base excitation and impulse excitation test on a foam-mass system. The foam used was the same in all of the experiments, thus obtaining all the responses on the same foam sample which helps eliminate …


Waste Heat Recovery Options In A Large Gas-Turbine Combined Power Plant, Ularee Upathumchard Oct 2014

Waste Heat Recovery Options In A Large Gas-Turbine Combined Power Plant, Ularee Upathumchard

Open Access Theses

This study focuses on power plant heat loss and how to utilize the waste heat in energy recovery systems in order to increase the overall power plant efficiency. The case study of this research is a 700-MW natural gas combined cycle power plant, located in a suburban area of Thailand. An analysis of the heat loss of the combustion process, power generation process, lubrication system, and cooling system has been conducted to evaluate waste heat recovery options. The design of the waste heat recovery options depends to the amount of heat loss from each system and its temperature. Feasible waste …


Transport In Ultra-Thin Heat Pipes For Low Power Applications, Yashwanth Yadavalli Oct 2014

Transport In Ultra-Thin Heat Pipes For Low Power Applications, Yashwanth Yadavalli

Open Access Theses

Heat pipes and vapor chamber heat spreaders offer a potential solution to the increasing thermal management challenges in thin-form-factor mobile computing platforms, where efficient spreading is required to simultaneously prevent overheating of internal components and formation of hot regions on the device exterior surfaces. The operating conditions for such applications are also characterized by low input heat fluxes, which in combination with the geometric constraints, give rise to unique performance limitations that require examination. This thesis aims to characterize the steady-state and transient heat pipe performance limitations unique to such ultra-thin form factors, and characterizes the key heat transfer mechanisms …


Dissolution Rate And Mechanism Of Metals In Molten Aluminum Alloy A380, Hengyu Zhu Oct 2014

Dissolution Rate And Mechanism Of Metals In Molten Aluminum Alloy A380, Hengyu Zhu

Open Access Theses

Shot sleeve is a very easily worn out part in a high-pressure die-casting machine due to serious dissolution of the area underneath the pouring hole. It is because during a normal pouring process, the high temperature molten aluminum will impact and dissolve that area of the shot sleeve by complex chemical and physical process. Rotation experiment was carried out to H13 and four kinds of refractory metal samples. SEM and EDS pictures were taken in order to investigate the microstructure and the dissolution mechanism of these materials. This suggests a high strength niobium is an ideal material for that area …


Coupled Fluid-Thermal Analysis Of Low-Pressure Sublimation And Condensation With Application To Freeze-Drying, Arnab Ganguly Oct 2014

Coupled Fluid-Thermal Analysis Of Low-Pressure Sublimation And Condensation With Application To Freeze-Drying, Arnab Ganguly

Open Access Dissertations

Freeze-drying is a low-pressure, low-temperature condensation pumping process widely used in the manufacture of bio-pharmaceuticals for removal of solvents by sublimation. The goal of the process is to provide a stable dosage form by removing the solvent in such a way that the sensitive molecular structure of the active substance is least disturbed. The vacuum environment presents unique challenges for understanding and controlling heat and mass transfer in the process. As a result, the design of equipment and associated processes has been largely empirical, slow and inefficient.^ A comprehensive simulation framework to predict both, process and equipment performance is critical …


Modeling The Dynamics And Stresses Of Elongated Particles In Vertical Axis Mixers, Xia Hua Oct 2014

Modeling The Dynamics And Stresses Of Elongated Particles In Vertical Axis Mixers, Xia Hua

Open Access Dissertations

Vertical axis mixers, such as high shear granulators and agitated filter dryers (AFDs), are commonly used in the processing of particulate materials. For example, AFDs are regularly used in the pharmaceutical industry to dry the wet active pharmaceutical ingredient (API) particles. During the drying process, an impeller blade agitates the bed to increase the drying rate and enhance drying uniformity. Unfortunately, the needle-shaped API particles tend to flow poorly, are frequently damaged, and can sometimes form undesirable agglomerates, causing manufacturing inefficiencies, flow stoppages, and unpredictable product quality. Therefore, it is important to gain an improved understanding of the system's particle …