- Dayton, Ohio, United States
Kevin Hallinan
University of Dayton, Mechanical Engineering, Faculty Member
Research Interests:
The operation of Capillary Pumped Loops (CPL's) in low gravity has generally been unable to match ground-based performance. The reason for this poorer performance has been elusive. In order to investigate the behavior of a CPL in... more
The operation of Capillary Pumped Loops (CPL's) in low gravity has generally been unable to match ground-based performance. The reason for this poorer performance has been elusive. In order to investigate the behavior of a CPL in low-gravity, an idealized, glass CPL experiment was constructed. This experiment, known as the Capillary-driven Heat Transfer (CHT) experiment, was flown on board the Space Shuttle Columbia in July 1997 during the Microgravity Science Laboratory mission. During the conduct of the CHT experiment an unexpected failure mode was observed. This failure mode was a result of liquid collecting and then eventually bridging the vapor return line. With the vapor return line blocked, the condensate was unable to return to the evaporator and dry-out subsequently followed. The mechanism for this collection and bridging has been associated with long wavelength instabilities of the liquid film forming in the vapor return line. Analysis has shown that vapor line blockage in present generation CPL devices is inevitable. Additionally, previous low-gravity CPL tests have reported the presence of relatively low frequency pressure oscillations during erratic system performance. Analysis reveals that these pressure oscillations are in part a result of long wavelength instabilities present in the evaporator pores, which likewise lead to liquid bridging and vapor entrapment in the porous media. Subsequent evaporation to the trapped vapor increases the vapor pressure. Eventually the vapor pressure causes ejection of the bridged liquid. Recoil stresses depress the meniscus, the vapor pressure rapidly increases, and the heated surface cools. The process then repeats with regularity.
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The objective of the report is to provide an up-to-date technical and marketing assessment of gas-fired integrated appliances. The assessment was conducted by the Gas Appliance Technology Center. The oldest integrated system is the... more
The objective of the report is to provide an up-to-date technical and marketing assessment of gas-fired integrated appliances. The assessment was conducted by the Gas Appliance Technology Center. The oldest integrated system is the combination boiler-water heater. Several new versions of the system and a few integrated furnace-water heaters are currently marketed. While these integrated space and water heating systems may merit further evaluation, the integrated furnace-clothes dryer concept appears most worthy of further developmental study. A gas furnace-clothes dryer was marketed through 1960, but lost popularity to the electric clothes dryer. A gas-fired energy and space saving integrated furnace-clothes dryer, or perhaps a modular integrated furnace-water heater-clothes dryer, should be attractive to lower income purchasers and renters of condominiums, apartments and factory-built trailer homes.
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An investigation of thermocapillary effects on a heated meniscus formed by a volatile liquid in a vertical capillary tube has been conducted. This investigation is primarily experimental although analysis is presented to gain insights... more
An investigation of thermocapillary effects on a heated meniscus formed by a volatile liquid in a vertical capillary tube has been conducted. This investigation is primarily experimental although analysis is presented to gain insights into the experimental results. The work was motivated by the importance of the evaporation process from porous or grooved media that are integral to the operation of capillary-driven heat transport devices such as heat pipes and capillary-driven loops. The research addressed the heat transfer characteristics of a capillary pore system. It was shown that the heat transfer effectiveness of the evaporating meniscus was reduced due to interfacial thermocapillary stresses. The effect of thermocapillary stresses on the heat transfer characteristics on single capillary pore heat transfer devices is shown to be a function of the non-dimensional thermocapillary stress (Marangoni number). This was demonstrated for different capillary pore sizes and working fluid conditions. Results include data for inside diameters of 0.5, 1, and 2 mm and liquid subcoolings of 18, 10, and 0 C. For large pores, it was shown that the heat transfer is controlled by convection.
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ABSTRACT In response to both global and local challenges, the University of Dayton is committed to building a net-zero energy student residence, called the Eco-house. A unique aspect of the Eco-house is the degree of student involvement;... more
ABSTRACT In response to both global and local challenges, the University of Dayton is committed to building a net-zero energy student residence, called the Eco-house. A unique aspect of the Eco-house is the degree of student involvement; in accordance with UD’s mission, interdisciplinary student teams from mechanical engineering, civil engineering and the humanities are leading the design effort. This paper discusses the conceptual design of a net-zero energy use campus residence, and the analysis completed thus far. Energy use of current student houses is analyzed to provide a baseline and to identify energy saving opportunities. The use of the whole-system inside-out approach to guide the overall design is described. Using the inside-out method as a guide, the energy impacts of occupant behavior, appliances and lights, building envelope, energy distribution systems and primary energy conversion equipment are discussed. The design of solar thermal and solar photovoltaic systems to meet the hot water and electricity requirements of the house is described. Eco-house energy use is simulated and compared to the energy use of the existing houses. The analysis shows the total source energy requirements of the Eco-house could be reduced by about 340 mmBtu per year over older baseline houses, resulting in CO2 emission reductions of about 54,000 lb per year and utility cost savings of about $3,000 per year. Detailed cost analysis and cost optimization have not been performed but are critical aspects of the UD Eco-house project, which will be performed in the future.
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Traditional approach for reducing energy and waste in industrial processes typically focus on improving the efficiency of the primary energy conversion equipment. Unfortunately, this approach frequently results in incremental improvement... more
Traditional approach for reducing energy and waste in industrial processes typically focus on improving the efficiency of the primary energy conversion equipment. Unfortunately, this approach frequently results in incremental improvement at high costs, since most energy and mass conversion equipment is relatively efficient to begin with and upgrading to higher efficiency equipment is usually quite costly.In this article, we describe
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In low gravity, the solid-liquid inter-molecular surface forces are comparable to capillary and gravitational forces at significantly greater film thickness (1 approximately 10 microns), than is possible in earth's... more
In low gravity, the solid-liquid inter-molecular surface forces are comparable to capillary and gravitational forces at significantly greater film thickness (1 approximately 10 microns), than is possible in earth's gravity (0.01 approximately 0.1 microns). Therefore, advanced microscale optical techniques to measure the film thickness, heat transport, and liquid velocity fields in the transition film region of an extended meniscus; probing,
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ABSTRACT The research aims at building a highly effective, miniaturized electrohydrodynamic pumped actuator. The actuator would provide greater performance in terms of higher force, higher displacement and equivalent bandwidth to the... more
ABSTRACT The research aims at building a highly effective, miniaturized electrohydrodynamic pumped actuator. The actuator would provide greater performance in terms of higher force, higher displacement and equivalent bandwidth to the so-called smart materials (piezoelectric and magnetostrictive) actuators of comparable size. The EHD actuators find applications in active structure-borne noise abatement, active vibration control, precision pointing. The on-going research aims at parametrically understanding the actuator with respect to its geometry, contained dielectric fluid medium and electric fields. A multitude of prototypes will be designed, fabricated and tested to provide experimental benchmarking of the model predictions. At the same time, this experimental bench marking will provide practical expertise in both fabricating the concept and incorporating it into smart structures.
ABSTRACT Historical residential electricity data and natural gas consumption data were collected for, respectively, 1,200 and 178 residences in a small town in the USA. These data were merged with local building and weather databases, and... more
ABSTRACT Historical residential electricity data and natural gas consumption data were collected for, respectively, 1,200 and 178 residences in a small town in the USA. These data were merged with local building and weather databases, and energy consumption models were developed for each residence, revealing substantial variation in heating and cooling intensity. After estimating approximate physical building characteristics, energy profiles for each residence were calculated, and savings from adoption of the most cost-effective energy-efficiency measures for each residence were estimated. Effectively, we wish to leverage commonly available data sets to infer characteristics of building envelopes and equipment, without the need for detailed on-site audits. This study evaluates the potential energy savings for the residences studied and, by extrapolation, for the entire town, as a function of cost if the savings measures were to be implemented in rank-order of cost effectiveness to show that savings penetration for the community comes with nonlinearly increasing cost. The results show that nearly a 32 % collective savings in HVAC energy use could be achieved with a collective levelized cost for energy-saving measures of $10/mmBTU saved if the most cost-effective measures among the entire community are implemented first.
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ABSTRACT Research is presented that investigates the potential for solar power generation with battery energy storage for reducing the effective cost of energy delivered to residential customers if real time pricing is present. A linear... more
ABSTRACT Research is presented that investigates the potential for solar power generation with battery energy storage for reducing the effective cost of energy delivered to residential customers if real time pricing is present. A linear optimization approach is developed based upon a two-step process. In step one, given a specified solar array area and battery capacity, the optimal means to meet loads based upon grid power, solar power, and/or battery power is determined. This analysis considers an expected life-span of the solar panel. With these results established, in the next step, the capital costs for the solar arrays and batteries are considered for each point (solar area and battery capacity) in the design space. Ultimately, the results illuminate the most cost effective means to provide power to customers for the chosen system.
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ABSTRACT A new type of actuation device has been conceptualized that meets the needs of both large displacement, force and bandwidth within a package more compact than currently available magnetostrictive and stack-type piezoelectric... more
ABSTRACT A new type of actuation device has been conceptualized that meets the needs of both large displacement, force and bandwidth within a package more compact than currently available magnetostrictive and stack-type piezoelectric actuators of similar rating. This concept relies on micro- scale electrohydrodynamic (EHD) pumping of a dielectric liquid within small channels. Configured as an actuator, the EHD pump(s) would be used to move fluid between two reservoirs - each having a compliant membrane that interfaces to the world to provide the means to achieve vibration cancellation or micro actuation.
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... at Google Indexer on August 11, 2010 jim.sagepub.com Downloaded from Page 3. lating liquids. In his experiments, the free ions were created by corona discharges. ... Okapal [7] examined the generation of a traveling wave by using a... more
... at Google Indexer on August 11, 2010 jim.sagepub.com Downloaded from Page 3. lating liquids. In his experiments, the free ions were created by corona discharges. ... Okapal [7] examined the generation of a traveling wave by using a single-phase volt-age excitation. ...
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Research has been conducted to observe the operation of a capillary-pumped loop (CPL) in both normal and low-gravity environments in order to ascertain the causes of device failure. The failures of capillary pumped loops in low gravity... more
Research has been conducted to observe the operation of a capillary-pumped loop (CPL) in both normal and low-gravity environments in order to ascertain the causes of device failure. The failures of capillary pumped loops in low gravity are not understood and the available data for analyzing the failures has been scarce. To observe failure in these devices, an idealized experimental CPL was configured for testing. The experimental test loop was constructed of Pyrex tubing to allow for visualization of system operations. Heat was added to the liquid on the evaporator side of the loop using resistance heaters and removed on the condenser side via forced convection of ambient air. A video camera was used to record the behavior of both the condenser and the evaporator menisci simultaneously. Low-gravity experiments were performed during the Microgravity Science Laboratory mission onboard the Space Shuttle Columbia in July of 1997. From this experiment, wall temperature and vapor pressure...
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... technology . Finally, Martin described progress in the scale-up of thermoelectric quantum well thermoelectrics. values approaching 5 were reported . ... range . Relative to aircraft energy harvesting from power electronics, Hallinan... more
... technology . Finally, Martin described progress in the scale-up of thermoelectric quantum well thermoelectrics. values approaching 5 were reported . ... range . Relative to aircraft energy harvesting from power electronics, Hallinan et al. ...
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... Abstract. A mathematical model is developed to describe the micro-/nano-scale fluid flow and heat/mass transfer phenomena in an evaporating extended meniscus, focusing on the transition film region under non-isothermal interfacial... more
... Abstract. A mathematical model is developed to describe the micro-/nano-scale fluid flow and heat/mass transfer phenomena in an evaporating extended meniscus, focusing on the transition film region under non-isothermal interfacial conditions. ...
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The new ABET EC2000 accreditation guidelines call for greater emphasis on social and ethical issues in the education of engineering students. Universities are responding in varied ways - generally through increased liberal arts content... more
The new ABET EC2000 accreditation guidelines call for greater emphasis on social and ethical issues in the education of engineering students. Universities are responding in varied ways - generally through increased liberal arts content and, in a few instances, through design activities, but generally, design education focuses primarily on the technical and process aspects. This is especially true in the
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Active thermal control was achieved by using an electrohydrodynamically (EHD) assisted micro heat pipe array. A simulation model of temperature control of EHD micro heat pipes was established in a Matlab Sinulink environment. An... more
Active thermal control was achieved by using an electrohydrodynamically (EHD) assisted micro heat pipe array. A simulation model of temperature control of EHD micro heat pipes was established in a Matlab Sinulink environment. An experimental model was designed and fabricated to verify the model and identify the factors most influential to the thermal control via EHD micro heat pipe array. Good correspondence between simulations and experiments was achieved. Electric field intensity, set-point temperature and the gap between the upper and lower set-point temperatures were shown to have a dramatic influence on the temperature control.
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Residential building energy use is an important contributor to greenhouse gas emissions and in the United States represents about 20% of total energy consumption. A number of previous macro-scale studies of residential energy consumption... more
Residential building energy use is an important contributor to greenhouse gas emissions and in the United States represents about 20% of total energy consumption. A number of previous macro-scale studies of residential energy consumption and energy-efficiency improvements are mainly concerned with national or international aggregate potential savings. In this paper we look into the details of how a collection of specific homes in one region might reduce energy consumption and carbon emissions, with particular attention ...
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The operation of Capillary Pumped Loops (CPL's) in low gravity has generally been unable to match ground-based performance. The reason for this poorer performance has been elusive. In order to investigate the behavior of a CPL in... more
The operation of Capillary Pumped Loops (CPL's) in low gravity has generally been unable to match ground-based performance. The reason for this poorer performance has been elusive. In order to investigate the behavior of a CPL in low-gravity, an idealized, glass CPL experiment was constructed. This experiment, known as the Capillary-driven Heat Transfer (CHT) experiment, was flown on board the Space Shuttle Columbia in July 1997 during the Microgravity Science Laboratory mission. During the conduct of the CHT experiment an unexpected failure mode was observed. This failure mode was a result of liquid collecting and then eventually bridging the vapor return line. With the vapor return line blocked, the condensate was unable to return to the evaporator and dry-out subsequently followed. The mechanism for this collection and bridging has been associated with long wavelength instabilities of the liquid film forming in the vapor return line. Analysis has shown that vapor line blockag...
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Despite the climate commitments made by countries in the Paris Climate Agreement adopted in 2015 and reinforced during COP 21 and with notably less success during COP 22, world carbon emissions increased in both 2021 and 2022. It is... more
Despite the climate commitments made by countries in the Paris Climate Agreement adopted in 2015 and reinforced during COP 21 and with notably less success during COP 22, world carbon emissions increased in both 2021 and 2022. It is increasingly unlikely that the world will achieve the targeted 50% carbon reduction by 2030, the reduction approximately needed for reducing global temperature rise since the beginning of the Industrial Revolution to less than 1.5 deg. C. At the same time, there remain nearly 2 billion people in the world who have no or highly unreliable access to power. In developed countries, access to both clean energy and energy efficiency investment in residences within low to moderate income communities has also lagged. This paper provides a review of the “Productive Use of Energy (PUE)”, which is a means to add value to solar energy mini- and micro-grids to ensure investment worthiness and add more value to the communities being served. In this context, it posits ...
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Building energy audits are both expensive, on the order of $0.50(US)/sf [1], and there aren’t enough auditors to survey the entire building stock in the U.S. Needed are lower cost automated approaches for rapidly evaluating the energy... more
Building energy audits are both expensive, on the order of $0.50(US)/sf [1], and there aren’t enough auditors to survey the entire building stock in the U.S. Needed are lower cost automated approaches for rapidly evaluating the energy effectiveness of buildings. A key element of such an approach would be automated measurements of envelope R-values. Proposed is the use of single point-in-time thermal images potentially obtainable from drive-by thermal imaging to infer wall and window R-values. A data mining based approach is proposed, which seeks to calibrate the measured exterior wall temperatures to known and measured R-values for a small subset of residences. In this approach, visual imagery is first used to determine the wall emissivity based on the color of the wall siding in order to yield an estimate of the wall temperature. A Random Forest model is developed using the training set comprised of the residences with known R-value. This model can then be used to estimate R- and C...
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EXERGY ANALYSIS FOR INDUSTRIAL ENERGY ASSESSMENT Bader, Wayne Thomas University of Dayton, 2000 Advisor: Dr. J. Kelly Kissock Traditional approaches to improving energy efficiency often focus on leak-plugging and housekeeping efforts to... more
EXERGY ANALYSIS FOR INDUSTRIAL ENERGY ASSESSMENT Bader, Wayne Thomas University of Dayton, 2000 Advisor: Dr. J. Kelly Kissock Traditional approaches to improving energy efficiency often focus on leak-plugging and housekeeping efforts to avoid wasting energy. In many cases however, the way energy is used, rather than the amount used, is the primary cause of inefficiency. Exergy analysis provides a thermodynamic basis for optimizing energy systems. By considering the quality of energy as well as the quantity, the true thermodynamic efficiencies can be quantified and proper priorities for improvement projects can be established. In spite of its value for optimizing thermodynamic systems, exergy analysis has seen only limited use as a practical tool for industrial energy assessment. In this thesis, the energy and exergy efficiencies of two common industrial processes, air compression and aluminum melting, are developed. Methods for improving the processes are quantitatively discussed. F...
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As the interconnectedness of the world grows, the need to prepare college students capable of addressing complexity likewise grows. In this context, the University of Dayton has developed and tested a transdisciplinary model for... more
As the interconnectedness of the world grows, the need to prepare college students capable of addressing complexity likewise grows. In this context, the University of Dayton has developed and tested a transdisciplinary model for education. This model links multiple classes from different disciplines via a common theme and within a common space. It also employs an educational model premised on the following trajectory: disciplinary content development / transdisciplinary observation (empathy); transdisciplinary disruption leading to “A-Ha” observations which transform the disciplinary directions; and lastly transdisciplinary informed design and research. Central to this model is a 3,500 square foot common space used only by the classes participating in the experience. In this space classes share their reflections and content with other classes via both personal linkages and analog communications. The other classes respond to these from their disciplinary and personal perspectives. Th...