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Full-Text Articles in Mechanical Engineering

Design And Characterization Of A High Pressure Flow Loop For Heat Transfer Experiments Of Supercritical Carbon Dioxide, Joseph Sauerbrun Oct 2023

Design And Characterization Of A High Pressure Flow Loop For Heat Transfer Experiments Of Supercritical Carbon Dioxide, Joseph Sauerbrun

Doctoral Dissertations and Master's Theses

Supercritical carbon dioxide (sCO2) sees heightened heat transfer characteristics near its critical point due to its drastically changing thermophysical properties. Conventional single phase heat transfer theory was not developed to capture this nonlinear variation in properties and cannot predict the heat transfer characteristics of sCO2 to a practical level useful for design. To delve deeper into the behavior near the critical point and shed light on this crucial phenomenon, a state-of-the-art closed flow loop was developed. This setup enabled convective heat transfer experiments of sCO2 under diverse boundary conditions and test section geometries. Key components of the loop include the …


The Influence Of Mixing Duct Length And Phase Of Flight On Wall Temperatures Of A Rocket Based Combined Cycle Engine In Ejector And Air-Augmented Modes, Jonathan Grow Jul 2023

The Influence Of Mixing Duct Length And Phase Of Flight On Wall Temperatures Of A Rocket Based Combined Cycle Engine In Ejector And Air-Augmented Modes, Jonathan Grow

Doctoral Dissertations and Master's Theses

Rocket Based Combined Cycle (RBCC) engines have been theorized as a possible means of powering launch vehicles and high-speed atmospheric vehicles. By incorporating aspects of both air-breathing and rocket propulsion, RBCC engines promise up to a 230 % increase in specific impulse over traditional chemical rocket propulsion by entraining a secondary flow of atmospheric air and mixing it with the exhaust of a rocket motor. Students within the Embry-Riddle Future Space Explorers and Developers Society (ERFSEDS) identified a
problem of excessive heating and structural failure of the mixing duct during launch and transonic flight of a student-built flight test vehicle. …


Advances In Spacecraft Thermal Control, Sandra K. S. Boetcher, Robert C. Consolo Jr. Jun 2023

Advances In Spacecraft Thermal Control, Sandra K. S. Boetcher, Robert C. Consolo Jr.

Publications

Spacecraft thermal management is critical for ensuring mission success, as it affects the performance and longevity of onboard systems. A comprehensive overview of the state of the art in spacecraft thermal control solutions, as well as a design methodology framework for efficient and effective thermal management, is provided. Various thermal control solutions, including coatings, insulation, heat pipes, phase-change materials, conductive materials, thermal devices, actively pumped fluid loops, and radiators, are discussed along with the primary sources of heat loading in space. The need for accurate modeling and analysis of the thermal environment to identify appropriate thermal control solutions and design …


Atmospheric Carbon Capture: A Review On Current Technologies And Analysis Of Energy Consumption For Various Direct Air Capture (Dac) Systems, Jennifer Perskin May 2023

Atmospheric Carbon Capture: A Review On Current Technologies And Analysis Of Energy Consumption For Various Direct Air Capture (Dac) Systems, Jennifer Perskin

Doctoral Dissertations and Master's Theses

Carbon dioxide (CO2) capture is a crucial approach to reducing greenhouse gases in the atmosphere to directly combat climate change. Major components of the technology to desublimate CO2 at cryogenic temperatures are mature and have the potential to be applied to build large Arctic/Antarctic direct-air CO2 capture plants. Pressure swing adsorption another gas separation technique used in industry today that can be modified for atmospheric carbon capture. The discussion of energy consumption for cryogenic and combined direct air capture systems is explored in this study. The investigation of precompression of atmospheric air for a direct-air capture …


Additive Manufacturing For Phase Change Thermal Energy Storage And Management, Thomas B. Freeman Apr 2023

Additive Manufacturing For Phase Change Thermal Energy Storage And Management, Thomas B. Freeman

Doctoral Dissertations and Master's Theses

Phase change materials can enhance the performance of energy systems by time shifting or reducing peak thermal loads. Certain electronic devices such as batteries, laser systems, or electric vehicle power electronics are highly transient and require pulse heat dissipation. Heat sinks, or thermal management devices made of a phase change material can absorb large heat spikes while maintaining a constant temperature. Additive manufacturing techniques hold tremendous potential to enable co-optimization of material properties and device geometry, while potentially reducing material waste and manufacturing time. Recently, a few efforts have emerged that employ additive manufacturing techniques to integrate a phase change …


Experimental And Numerical Analysis Of A Commercial Phase Change Material Melting At Different Inclinations, Andrew Heiles Apr 2023

Experimental And Numerical Analysis Of A Commercial Phase Change Material Melting At Different Inclinations, Andrew Heiles

Doctoral Dissertations and Master's Theses

The study of various phase change materials (PCM), experimentally and numerically, have been completed over the past several years to address their feasibility and potential when used in latent heat thermal energy storage (LHTES) systems for a variety of potential applications. Previous studies have investigated changes into the type of PCM used in the system as well as the system configuration, ranging from boundary conditions to internal and external geometries and orientations of the system. The present study focused on conducting experiments at different inclination angles and isothermal wall temperatures with the organic PCM PureTemp37, and continued with a numerical …


Thermal Boundary Condition Effects On Local Supercritical Co2 Heat Transfer Trends In Tubes, Nicholas C. Lopes Apr 2023

Thermal Boundary Condition Effects On Local Supercritical Co2 Heat Transfer Trends In Tubes, Nicholas C. Lopes

Doctoral Dissertations and Master's Theses

Supercritical carbon dioxide (sCO2) is a promising heat transfer fluid for the refrigeration and power generation industries due to its unique thermal properties and low environmental impact. To understand it as an alternative to traditional working fluids, the thermophysical and heat transfer phenomena of sCO2 are often studied using simplified geometries (tubes). Focus has been placed on investigating averaged heat transfer trends under an array of flow conditions with either a constant wall heat flux, constant wall temperature, or conjugate thermal boundary condition. Less emphasis has been placed on studying local sCO2 heat transfer developments. Tubular sCO2 numerical models that …


Biomass Characterization And Insulation Optimization Studies, Hussein Awad Kurdi Saad Nov 2022

Biomass Characterization And Insulation Optimization Studies, Hussein Awad Kurdi Saad

Doctoral Dissertations and Master's Theses

This study indicates how biomass materials can be effectively used as naturally sustainable alternatives to insulation materials. Barley grains and oak leaves, straw, and jute are collected, and crushed into powders/ chopped pieces. The physical characteristics are measured to characterize each powder. The biomass powder reinforced composites are manufactured in varying weight ratios. The density and thermal conductivity of composite materials are measured. The properties of composites compared to those of commercial insulation materials are found to be close to them. Furthermore, genetic algorithms (GA) can be used to achieve multi-objective optimization entailing maximizing insulation (minimizing heat transfer) and simultaneously …


Comprehensive Review Of Heat Transfer Correlations Of Supercritical Co2 In Straight Tubes Near The Critical Point: A Historical Perspective, Nicholas C. Lopes, Yang Chao, Vinusha Dasarla, Neil P. Sullivan, Mark Ricklick, Sandra Boetcher Aug 2022

Comprehensive Review Of Heat Transfer Correlations Of Supercritical Co2 In Straight Tubes Near The Critical Point: A Historical Perspective, Nicholas C. Lopes, Yang Chao, Vinusha Dasarla, Neil P. Sullivan, Mark Ricklick, Sandra Boetcher

Publications

An exhaustive review was undertaken to assemble all available correlations for supercritical CO2 in straight, round tubes of any orientation with special attention paid to how the wildly varying fluid properties near the critical point are handled. The assemblage of correlations, and subsequent discussion, is presented from a historical perspective, starting from pioneering work on the topic in the 1950s to the modern day. Despite the growing sophistication of sCO2 heat transfer correlations, modern correlations are still only generally applicable over a relatively small range of operating conditions, and there has not been a substantial increase in predictive capabilities. Recently, …


Preliminary Study Of Shape-Memory Alloy Torsional Tubes As Thermal Management Actuators Under Non-Ideal Conditions, Paula Sanjuan Espejo, Samuel Desloover, Devon Hardy, Mark Ricklick, Frederick Calkin, David Foutch Jun 2022

Preliminary Study Of Shape-Memory Alloy Torsional Tubes As Thermal Management Actuators Under Non-Ideal Conditions, Paula Sanjuan Espejo, Samuel Desloover, Devon Hardy, Mark Ricklick, Frederick Calkin, David Foutch

Publications

Shape-memory alloys (SMAs) have been used in many engineering applications because of their shape-memory effect and pseudoelasticity. SMA behavior is well understood under steady and constant temperature and loading conditions, whereas transient and non-ideal conditions effects should be further investigated. In this research, SMA torque tubes are studied for use in thermal management applications as self-regulated actuators responding to a process fluid with changes in temperature, with the goal of improved system efficiency by keeping components at an optimal temperature. When utilized in a thermal management configuration, it is likely that the SMA’s thermal environment will be different than that …


Phase Change Material And Applications, Sandra Kathleen Sparr Boetcher, Rafael M. Rodriguez, Kashif Nawas, Melissa Ann Messenger, Casey Josh Troxler, Thomas Benjamin Freeman Jun 2022

Phase Change Material And Applications, Sandra Kathleen Sparr Boetcher, Rafael M. Rodriguez, Kashif Nawas, Melissa Ann Messenger, Casey Josh Troxler, Thomas Benjamin Freeman

Publications

A thermal energy storage heat exchanger can include a core defining a plurality of airflow passages to receive an air­stream therethrough. The core can be made of a composite of a phase change material shape-stabilized by a polymer. The phase change material can be structurally supported by the polymer and the phase change material can be config­ured to change phases to store energy from and deliver stored energy to the airstream when the airflow passes through the core.


Experimental And Numerical Investigation Of Lauric Acid Melting At Suboptimal Inclines, Casey J. Troxler Apr 2022

Experimental And Numerical Investigation Of Lauric Acid Melting At Suboptimal Inclines, Casey J. Troxler

Doctoral Dissertations and Master's Theses

Validation experiments are the baseline for completing numerical studies for engineering design. Applications of the enthalpy-porosity model have expanded in research with the growth of new technologies such as metal additive manufacturing or the renewed interest in thermal energy storage for supplementing renewable energy. A simplified experiment examining the melting behavior of lauric acid from an isothermal surface has become a common case for validating the performance of numerical models. Several studies of this rectangular experiment have been repeatedly used as model validation in a variety of problem conditions.

The first part of this study presents experimental data for the …


Cool Thermal Energy Storage: Water And Ice To Alternative Phase Change Materials, Sandra K. S. Boetcher Jan 2022

Cool Thermal Energy Storage: Water And Ice To Alternative Phase Change Materials, Sandra K. S. Boetcher

Publications

Cool thermal energy storage has a long history dating back to ancient times with modern developments beginning in the mid-nineteenth century where blocks of ice were cut from frozen lakes for cooling applications. Today, the prevalent mode of thermal energy storage is the utilization of ice tanks in commercial buildings for peak shaving and load shifting. In this chapter, a summary of different types of water/ice thermal energy storage systems is provided; an overview of alternative phase change materials for use in cool thermal energy storage is given; and alternative phase change material thermal energy systems, their implementation, challenges, and …


Experimental Study Of Wall Bounded Harbor Seal Whisker Inspired Pin Geometries, Anish Prasad, Mark Ricklick Jan 2022

Experimental Study Of Wall Bounded Harbor Seal Whisker Inspired Pin Geometries, Anish Prasad, Mark Ricklick

Publications

Conventional cylindrical/elliptical pins are one of the most widely used geometries in convection cooling systems and are used in the internal cooling of gas turbine blades and other applications, as they promote better heat transfer at the expense of large pressure losses and unsteadiness in the flow. The need to reduce pressure drop and maintain the heat transfer rates are a pressing requirement for a variety of industries to improve their cooling efficiency. One such prominent field of research is conducted in optimizing the design of pin geometries. In this study, a harbor seal whisker inspired geometry is being studied …


State-Of-The-Art Of Thermal Control Solutions To Establish A Modular, Multi-Orbit Capable Spacecraft Thermal Management System Design Methodology, Robert C. Consolo Jr Dec 2021

State-Of-The-Art Of Thermal Control Solutions To Establish A Modular, Multi-Orbit Capable Spacecraft Thermal Management System Design Methodology, Robert C. Consolo Jr

Doctoral Dissertations and Master's Theses

Today, the exploration and exploitation of space continues to become a more common occurrence. All types of spacecraft (S/C) utilize various types of thermal management solutions to mitigate the effects of thermal loading from the unforgiving vacuum of space. Without an appropriately designed thermal system, components on-board the S/C can experience failure or malfunction due to fluctuations in temperatures either beyond the designed operational parameters or unstable oscillating temperatures. The purpose of this study is to perform a comprehensive review of technologies available today that are being used for thermal management onboard S/C in addition to investigating the means to …


Numerical Simulation Of A Cryogenic Spray, Neel Kishorkumar Shah Dec 2021

Numerical Simulation Of A Cryogenic Spray, Neel Kishorkumar Shah

Doctoral Dissertations and Master's Theses

Cryogenic sprays have many applications in modern engineering. Cooling of electronic equipment subject to high heat flows, surgical ablation of gastrointestinal mucosae or orbital maneuvering are a few examples of their versatility. However, the atomization of a cryogenic liquid is a complex process. During such an event, aerodynamic effects associated with secondary atomization are further affected by thermodynamic flashing. A better understanding of the characteristics of cryogenic sprays is then necessary to allow for improved design and optimization in applications. The overarching objective of this study is to document such characteristics. The numerical simulation was performed over cryogenic nitrogen spray …


Moisture Affinity Of Hdpe/Phase-Change Material Composites For Thermal Energy Storage Applications, Sandra K. Boetcher, Thomas B. Freeman, Rafael M. Rodriguez, Kashif Nawaz Nov 2021

Moisture Affinity Of Hdpe/Phase-Change Material Composites For Thermal Energy Storage Applications, Sandra K. Boetcher, Thomas B. Freeman, Rafael M. Rodriguez, Kashif Nawaz

Publications

Moisture adsorption can degrade the structural integrity of thermal energy storage devices and can negatively impact the capacity and charging/discharging behavior. Steady-state and transient experiments are conducted at various operating temperatures to evaluate the moisture affinity of organic phase-change material (PCM) shape stabilized with high-density polyethylene (HDPE).


Desalination For Sustainable Water Production With An Emphasis On Low Pressure Distillation, Jessica Vivian Savage May 2021

Desalination For Sustainable Water Production With An Emphasis On Low Pressure Distillation, Jessica Vivian Savage

Doctoral Dissertations and Master's Theses

Freshwater resources depletion is a growing concern. This freshwater scarcity motivates research into seawater desalination as a means for alleviating the stresses on water demands. The primary methods of desalination include filtration and distillation. This paper explores the potential energy savings of vacuum distillation for seawater desalination to reduce the amount of energy needed to achieve phase change.

Depending on the vacuum boiler design, the vaporization mechanism may be boiling, evaporation, or cavitation. There is very little literature on cavitation that involves mass transfer, so cavitation is not developed here. This thesis focuses on standard models for boiling and evaporation …


System Level Model For Pumped Two-Phase Cooling Systems, Leitao Chen, Timothy Joseph Chainer, Pritish Ranjan Parida, Mark Delorman Schultz, Fanghao Yang Mar 2020

System Level Model For Pumped Two-Phase Cooling Systems, Leitao Chen, Timothy Joseph Chainer, Pritish Ranjan Parida, Mark Delorman Schultz, Fanghao Yang

Publications

Techniques are provided for system level modeling of two-phase cooling systems. In one example, a computer implemented method comprises determining, by a system operatively coupled to a processor, respective sets of steady state values for parameters at inlet-outlet junctions using a system model, wherein the determining is based on first user input specifying a cooling system design comprising a plurality of part objects, wherein adjacent part objects in a flow direction are connected at the inlet-outlet junctions. The computer-implemented method can also comprise generat­ing, by the system, a graphical display that depicts the respective sets of parameter values at the …


Residential Thermal Storage And Cooling, Joao Marcelo Rocha Belmonte, Jacob Anderson, Andrew Clarke, Daphne Forester, Bianca Hardtke, Josh Hartman, Marc D. Compere Jan 2020

Residential Thermal Storage And Cooling, Joao Marcelo Rocha Belmonte, Jacob Anderson, Andrew Clarke, Daphne Forester, Bianca Hardtke, Josh Hartman, Marc D. Compere

Sustainability Conference

No abstract provided.


Adaptable Clean Energy Laboratory, Joao Marcelo Rocha Belmonte, Marc D. Compere Jan 2020

Adaptable Clean Energy Laboratory, Joao Marcelo Rocha Belmonte, Marc D. Compere

Sustainability Conference

The Adaptable Clean Energy (ACE) Lab is a real-world, long term, test platform that will guide the courses of the Energy Systems track. The lab will provide realistic electrical and HVAC loads that mimic a solar powered office. The lab is a 20’ high cube shipping container modified with a door, windows, lights computers, air conditioner and appliances. The lab is Net-Zero and powered entirely from the sun. Two insulation test sections expose the exterior walls for research access to real external heat loads in a real building


Thermodynamic Model Of Co2 Deposition In Cold Climates, Sandra K. S. Boetcher, Ted Von Hippel, Matthew J. Traum Dec 2019

Thermodynamic Model Of Co2 Deposition In Cold Climates, Sandra K. S. Boetcher, Ted Von Hippel, Matthew J. Traum

Publications

A thermodynamic model, borrowing ideas from psychrometric principles, of a cryogenic direct-air CO2-capture system utilizing a precooler is used to estimate the optimal CO2 removal fraction to minimize energy input per tonne of CO2. Energy costs to operate the system scale almost linearly with the temperature drop between the ingested air and the cryogenic desublimation temperature of CO2, driving siting to the coldest accessible locations. System performance in three Arctic/Antarctic regions where the proposed system can potentially be located is analyzed. Colder ambient temperatures provide colder system input air temperature yielding lower CO2 removal energy requirements. A case is also …


Modelling Of Aerodynamic Process For Coal Waste Dump Located In Geodynamically Dangerous Zone, Elena Vishnevskaya, Alexander Kobylkin, Valeriya Musina, Andrian Batugin, Vladimir Ponomarev, Oksana Vorobyeva Jan 2019

Modelling Of Aerodynamic Process For Coal Waste Dump Located In Geodynamically Dangerous Zone, Elena Vishnevskaya, Alexander Kobylkin, Valeriya Musina, Andrian Batugin, Vladimir Ponomarev, Oksana Vorobyeva

Publications

Previously made evaluations show confinement of fire coal waste dumps to geodynamically dangerous zones which in this work are considered as borders of active blocks of the earth crust. According to the hypothesis under development, when disposing the dumps in geodynamically dangerous zones (GDZ), which have a high penetrating, aerodynamic relation of the dumps with the environment occurs, making the dumps firing possible. Firing of the dumps inflicts environmental, social and material damage. This research is aimed to study possible mechanism of gas mass transfer through GDZ into the body of dump on the base of computer modeling of aerodynamic …


Simulations On Optimization Of Liquid Spray Burners & Operating Parameters, Pallavi Gajjar, Vinayak Malhotra Jan 2019

Simulations On Optimization Of Liquid Spray Burners & Operating Parameters, Pallavi Gajjar, Vinayak Malhotra

International Journal of Aviation, Aeronautics, and Aerospace

Spray burners form an essential part of any liquid propulsion system as they are responsible for injecting, atomizing, mixing and combusting the liquid fuel. Spray combustion used in aerospace applications like the liquid rocket engines, gas turbines or any other controlled environment for that matter places a huge emphasis on safe and effective operations. These applications make use of relatively small amounts of propellant volumes to generate enormous amounts of energy through combustion for producing thrust. For such cases involving enormous energy interactions, combustion comes with its own set of challenges. The predominant challenge among them all is that of …


Thermal Removal Of Carbon Dioxide From The Atmosphere: Energy Requirements And Scaling Issues, Ted Von Hippel May 2018

Thermal Removal Of Carbon Dioxide From The Atmosphere: Energy Requirements And Scaling Issues, Ted Von Hippel

Publications

I conduct a systems-level study of direct air capture of CO2 using techniques from thermal physics. This system relies on a combination of an efficient heat exchanger, radiative cooling, and refrigeration, all at industrial scale and operated in environments at low ambient temperatures. While technological developments will be required for such a system to operate efficiently, those developments rest on a long history of refrigeration expertise and technology, and they can be developed and tested at modest scale. I estimate that the energy required to remove CO2 via this approach is comparable to direct air capture by other techniques. The …


In-House Fabrication Of Temperature Sensitive Paint For Turbine Cooling Research, Mayur D. Patel, Mark A. Ricklick Feb 2017

In-House Fabrication Of Temperature Sensitive Paint For Turbine Cooling Research, Mayur D. Patel, Mark A. Ricklick

Beyond: Undergraduate Research Journal

The Temperature Sensitive Paint (TSP) is a widely used method in measuring and visualizing flow separation and heat transfer. Compared to the cost and time consumption needed for methods such as pitot tubes, temperature sensitive paint is a cheaper alternative. Due to high usage in College of Engineering research projects, it was determined that in house fabrication of temperature sensitive paint would reduce time and cost limitations. For initial stages, literature research was performed to determine the recipe of intensity based TSP with luminophore and polymer binder that operated optimum at temperatures from 0-100°C. Europium III thenoyltrifluoroacetonate was determined to …


Determination Of Aqueous Surfactant Solution Surface Tensions With A Surface Tensiometer, Remelisa Esteves, Birce Dikici Ph.D, Matthew Lehman, Qayyum Mazumder, Nonso Onukwuba Nov 2016

Determination Of Aqueous Surfactant Solution Surface Tensions With A Surface Tensiometer, Remelisa Esteves, Birce Dikici Ph.D, Matthew Lehman, Qayyum Mazumder, Nonso Onukwuba

Beyond: Undergraduate Research Journal

Surfactant solutions are applicable to engineering systems for cooling equipment for electronics. Surfactants can be added to water to improve heat transfer. An application of using aqueous surfactant solutions can be through microchannel heat sink. Although it is ideal to redesign these systems to reduce heat, it is a costly method. Surfactant solutions at optimal solution concentration can be able to transfer heat quickly and effectively with minimum expense. The surface tension of surfactant solutions is an important parameter for boiling heat transfer and must be taken into consideration. The purpose of this research is to measure surface tension of …


Determination Of Surfactant Solution Viscosities With A Rotational Viscometer, Remelisa Esteves, Nonso Onukwuba, Birce Dikici Ph.D Nov 2016

Determination Of Surfactant Solution Viscosities With A Rotational Viscometer, Remelisa Esteves, Nonso Onukwuba, Birce Dikici Ph.D

Beyond: Undergraduate Research Journal

Aqueous surfactant solutions are used in engineering systems for improving boiling heat transfer. The purpose of this research is to determine the viscosities of surfactant solutions and to investigate the effect of composition on viscosity. The results obtained can possibly be used as reference for further study in the effects of surfactant solution viscosities on nucleate boiling. A rotational viscometer was used to determine the viscosities of three surfactant solutions – SLS, EH-14, and SA-9 – of various compositions at room temperature. It was discovered that the viscosities of SLS, EH-14, and SA-9 had a nearly consistent pattern as their …


Enthalpy-Based System-Model For Pumped Two-Phase Cooling Systems, Leitao Chen, Fanghao Yang, Pritish R. Parida, Mark Schultz, Timothy Chainer Jul 2016

Enthalpy-Based System-Model For Pumped Two-Phase Cooling Systems, Leitao Chen, Fanghao Yang, Pritish R. Parida, Mark Schultz, Timothy Chainer

Publications

The development of embedded chip cooling for 2D and 3D integrated circuits using pumped dielectric refrigerant has gained recent attention due to the ability to manage high heat densities and compatibility with electronics. Recent studies have focused on in-situ thermal and hydrodynamic phenomena (e.g. boiling and bubble dynamics) of two-phase flow boiling at micro-scales. In this paper we focus on the two-phase cooling system design including the cooling capability, size and coefficient of performance (COP). In implementing a two-phase cooling, a system-level computational model for two-phase cooling systems becomes necessary. Therefore, a computationally manageable and accurate one dimensional (1D) system …


Heating Element Including Carbon Nanotube (Cnt) Layer, Santhosh Kumar Loganathan, Virginie Rollin, Daewon Kim Apr 2016

Heating Element Including Carbon Nanotube (Cnt) Layer, Santhosh Kumar Loganathan, Virginie Rollin, Daewon Kim

Publications

Apparatus , materials , and techniques and techniques herein can include providing a deposited layer comprising a com posite material including carbon nanotubes ( CNTs ) . Accord ing to various examples , the composite can be applied to a substrate such as using a solution containing CNTs and other constituents such as sulfur . The solution can be spray applied to a substrate , or spin - coated upon a substrate , such as to provide a uniform , conductive , and optically - transpar ent film layer . In one application , such a film layer can be …