Engineering Commons^™

Residential Indoor Air Quality Study – Assessment And Mitigation, Giovanni Cerrato

Mechanical Engineering Theses

An increased awareness in residential indoor air quality (IAQ) has led to an increase in technologies that assist in improving IAQ. Two such technologies include Electro-static (ES) air cleaners and Photocatalytic Oxidizing (PCO) air cleaners. ES air cleaners remove particulate matter from indoor air, but are known to emit ozone, a contaminant, as a by-product. PCO air cleaners abate gaseous pollutants (i.e., Volatile Organic Compounds, VOCs); however, a lack of testing standards creates confusion about their effectiveness in improving IAQ in a real residential home. On the other hand, environmental variables such as temperature and humidity were found to affect …

Portable Drinking Water Cooler And Dispenser, Gustavo Hernandez-Lerena, Erik Torres, Caleb Francis Parham, Terry Leung

Mechanical Engineering

This document serves as the comprehensive report for the testing and building for the Portable Water-Cooling System by team AquaCool. Team AquaCool is comprised of four mechanical engineers with a passion to help the agricultural industry in their efforts to keep the health of the workers at their peak. The four engineers who partook in helping the farm workers are as follows: Caleb F. Parham, Erik Torres, Gustavo Hernandez-Lerena, and Terry Leung. To reduce the risk of heatstroke and other unwanted effects from the harsh working conditions during summer, a small and portable system was built to help in the …

Changing Climates And Extreme Weather For Minnesota, Patrick A. Tebbe

Mechanical and Civil Engineering Department Publications

Climate change is impacting the design, prediction, and operation of HVAC systems for the built environment, and will continue to do so for the foreseeable future. This presentation reviews climate predictions for the upper Midwest and how they will affect the HVAC industry. Topics such as changing design conditions, extreme weather impact, and increased electrification will be addressed.

Energy Analysis Of Heating, Ventilation, And Air Conditioning Systems, Erica Ferguson

Williams Honors College, Honors Research Projects

This project studied Heating, Ventilation, and Air Conditioning (HVAC) systems for commercial buildings. I completed an energy model Raleigh County Sheriff’s Department in West Virginia. This building’s HVAC has been completed by the consulting engineering firm: Scheeser Buckley Mayfield. I intern at this company, so they allowed me to use their original design as a basis for comparison. Load calculations, utility costs, energy consumption, and carbon footprint were derived from this energy analysis. The energy model compared three systems: variable air volume (VAV) with electric reheat, variable air volume with hydronic reheat, and variable refrigerant volume (VRV). Based on the …

Active Membrane Energy Exchanger For Air Cooling And Dehumidification, Songhao Wu, Andrew Fix, David M. Warsinger, James E. Braun

Discovery Undergraduate Interdisciplinary Research Internship

Heating, ventilation and air conditioning (HVAC) equipment consume 35% of total building energy use in the US, among which a large share is used for cooling and dehumidification. The majority of air dehumidification systems take the conventional approach of moisture condensation removal. It requires air to be cooled below its dew point temperature and is an energy-intensive process, especially for areas with hot and humid climates. Vapor selective membrane systems are promising alternatives for air dehumidification as they do not require cooling energy for latent (humidity) heat removal. It allows water vapor transport through the membrane while blocking air. Previous …

Development And Application Of A Digital Twin For Chiller Plant Performance Assessment, Mihir Kale

All Theses

As the complexity of industrial equipment continues to increase, the management of the individual machines and integrated operations becomes difficult without computer tools. The availability of streaming data from manufacturing floors, plant operations, and deployed fleets can be overwhelming to analyze, although it provides opportunities to improve performance. The use of dedicated monitoring systems in the plant and field to troubleshoot machinery can be integrated within a product lifecycle management (PLM) architecture to offer greater features. PLM offers virtual processes and software tools for the design, analysis, monitoring, and support of engineering systems and products. Within this paradigm, a digital …

Investigation Of The Prevalence Of Faults In The Heating, Ventilation, And Air-Conditioning Systems Of Commercial Buildings, Amir Ebrahimifakhar

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

This dissertation describes a large-scale investigation of heating, ventilation, and air-conditioning (HVAC) fault prevalence in commercial buildings in the United States. A multi-year dataset with 36,556 pieces of HVAC equipment including air handling units (AHUs), air terminal units (ATUs), and packaged rooftop units (RTUs) was analyzed to determine values for several HVAC fault prevalence metrics. The primary source of data for this study comes from three commercial fault detection and diagnostics (FDD) providers. Since each FDD provider uses different terms to refer to the same fault in an HVAC system, a mapping function was created for each FDD provider’s dataset, …

Dynamic Hvac Energy Management Using Commercial Building Occupancy Metrics & Neural Networks, Krishna Chaitanya Jagadeesh Simma

Civil Engineering ETDs

With the rise of technology use in buildings, it is now possible to collect data that can be used to improve building energy consumption. One factor that has significant impact on building energy consumption is occupancy. Recent studies have shown promising results in obtaining occupancy information from existing infrastructure such as WiFi router networks. However, these existing frameworks require additional investments through software upgrades, added infrastructure, computational resources, and may raise occupant privacy concerns. Additionally, with occupant thermal comfort statistics being lower than ASHAREA specified standards, a novel approach for indoor climate control is needed. To address the limitations in …

Sustainable Tiny Home, Abigail Jessica Jones, Vince John Bugni, Sean Robert Paddy, Cameron Michael Gross

Mechanical Engineering

As housing prices and environmental concerns continue to increase, many people are looking for cheaper and more sustainable ways to live. A solution to both problems is building homes with smaller footprints which incorporate renewable energy and water-reclamation systems. In addition, adding a roof pond system to the dwelling also reduces the need for heating and cooling. The roof pond system uses a water bladder on the roof which acts as a heat-sink and moveable insulation panels. This document contains the process for our final design along with results from testing the verification prototype.

Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes, Florida Solar Energy Center, Tanvir Khan

FSEC Energy Research Center®

Existing evidence strongly suggests that viral infectious diseases can be transmitted via an airborne route across distances in indoor environments. Accordingly, the risk of airborne transmission within homes should be managed. The public health emergency associated with SARS-CoV-2 makes controlling airborne transmission of respired viruses in indoor environments critical, especially in poorly ventilated indoor environments. The effectiveness of engineering interventions requiring minor efforts that create a negative-pressure isolation zone (IZ) for a contagious person has yet to be tested for existing residential homes.

To mitigate the risk of airborne virus transmission and maximize health protection for the population in existing …

Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes -- Fact Sheet, Florida Solar Energy Center, Tanvir Khan

FSEC Energy Research Center®

The FSEC Energy Research Center at the University of Central Florida performed research to test the effectiveness of interventions to isolate an ill person recovering from a contagious disease in a single-family home from the rest of the occupants in the home. Focus was placed on interventions requiring minor cost and effort on the part of the occupants.

DOE/GO-102021-5537, https://www.nrel.gov/docs/fy21osti/79519.pdf

Photocatalytic Inactivation Efficacy Of Sars-Cov-2 In Hvac Systems, Andrew J. Freeman, Sudharshan Anandan, Ernest R. Blatchley Iii, W. Travis Horton, David M. Warsinger

Discovery Undergraduate Interdisciplinary Research Internship

The coronavirus pandemic has emphasized a need for robust and reliable air purification systems in buildings; with that comes a need for a standardized testing methodology for air purification technologies in HVAC air circulation systems. One such method of air purification is photocatalytic oxidation (PCO), a mechanism in which a catalyst irradiated by light produces reactive molecules that degrade a wide range of pollutants, including the aerosols that carry COVID. This technology has primarily been used in aqueous applications, but there have recently been developments in air purification that have made it a promising contender to existing technologies. One of …

Who's Leading: The Dance Between Mini-Splits And Existing Hvac Systems, Florida Solar Energy Center, Cheryn Metzger

FSEC Energy Research Center®

Recently, many utilities across the U.S. have provided incentives for ductless mini-split heat pumps due to their relatively high efficiencies. However, when these ductless mini-splits are installed in existing homes, utilities and researchers find that they are not living up to their energy saving potential, due to a lack of coordinated controls with the existing HVAC system. The Pacific Northwest National Laboratory (PNNL), the Florida Solar Energy Center (FSEC), and The Levy Partnership are all leading projects across the country to address this problem. The goal for this body of work is to determine which control strategies provide the most …

Active Noise Control Using Carbon Nanotube Thermophones: Case Study For An Automotive Hvac Application, Walker H. Nelson

Dissertations, Master's Theses and Master's Reports

The goal of this project was to reduce the overall noise levels emitted by the HVAC components in a vehicle’s cabin. More specifically, the feasibility of achieving this goal using two key technologies was investigated.

The first of these technologies, Active Noise Control (ANC), is a noise attenuation technique that relies on destructive interference that “cancels” unwanted noise. Typically used in situations where physical constraints prevent passive attenuation techniques from being used, ANC is known for its high size-to-effectiveness ratio. This benefit cannot be gained without a cost however; the complexity of ANC systems is significantly higher than their passive …

Hvac System Energy Audit For Leverett Elementary School, Connor Smalling

Biological and Agricultural Engineering Undergraduate Honors Theses

Leverett Elementary School is located in Fayetteville, AR. The school needs significant upgrades to its infrastructure. The Fayetteville Public School District has voted to pursue an Energy Services Performance Contract (ESPC) in order to finance the desired upgrades to Leverett Elementary, among other schools in the district.

The scope of this thesis was to perform an energy audit on the existing heating, ventilation, and air conditioning (HVAC) system. By using an energy modeling software, eQuest, the building and the existing base system were modeled to determine utility consumption. Three different HVAC system alternatives were analyzed against the base system by …

Evaluating Moisture Control Of Variable-Capacity Heat Pumps In Mechanically Ventilated, Low-Load Homes In Climate Zone 2a, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

The well-sealed, highly insulated building enclosures constructed by today's home building industry coupled with efficient lighting and appliances are achieving significantly reduced heating and cooling loads. These low-load homes can present a challenge when selecting appropriate space-conditioning equipment. Conventional, fixed-capacity heating and cooling equipment is often oversized for small homes, causing increased first costs and operating costs. Even if fixed-capacity equipment can be properly specified for peak loads, it remains oversized for use during much of the year. During these part-load cooling hours, oversized equipment meets the target dry-bulb temperatures very quickly, often without sufficient opportunity for moisture control. The …

Modeling Of Thermal Dynamics In Chevrolet Volt Gen Ii Hybrid Electric Vehicle For Integrated Powertrain And Hvac Optimal Operation Through Connectivity, Nehal Doshi

Dissertations, Master's Theses and Master's Reports

Integrated thermal energy management across system level components in electric vehicles (EVs) and hybrid electric vehicles (HEVs) is currently an under explored space. The proliferation of connected vehicles and accompanying infrastructure in recent years provides additional motivation to explore opportunities in optimizing thermal energy management in EVs and HEVs with the help of this newly available connected vehicle data. This thesis aims to examine and analyze the potential to mitigate vehicle energy consumption and extend usable driving range through optimal control strategies which exploit physical system dynamics via controls integration of vehicle subsystems.

In this study, data-driven and physics-based models …

Impact Of Implementing A Dedicated Outdoor Air System In Parallel With A Multi-Zone Variable-Air Volume System On Energy Consumption, Thermal Comfort, And Life Cycle Cost, Khaled Alghamdi

Graduate Theses, Dissertations, and Problem Reports

Heating, Ventilating, and Air-Conditioning systems (HVAC) consume more than 40% of energy in commercial buildings, according to the Commercial Building Energy Consumption Survey in 2012. Therefore, efforts to reduce HVAC energy consumption would be significant in coping with energy-related issues. In that context and in order to enhance the indoor air quality without compromising for energy consumption, the concept of Dedicated Outdoor Air systems (DOAS) emerged.

The literature shows that the integration of DOAS with other HVAC systems has been studied widely, yet the impact of integrating DOAS in parallel with multi-zone Variable-Air Volume systems (multi-zone VAV) for an application …

The Effects Of Exhaust Vent Location On Thermal Comfort Inside The Residential Buildings Equipped With An Evaporative Cooling System, Armin Saraei

UNLV Theses, Dissertations, Professional Papers, and Capstones

Inlet and outlet conditions, Including size and location, have significant effects on the air distribution, temperature, humidity and thermal comfort in the buildings. In the current study, various strategies are presented for exhaust air vents and the effects of inlet and outlet vents locations are evaluated on providing thermal comfort in the residential and industrial buildings. To provide thermal comfort, three key factors need to be investigated based on ASHRAE standard 55- 2013 as follows: Comfort Zone, Thermal Sensation and Draft Rate. Flow distribution is studied as well in order to investigate the strategies, which make more vorticity in the …

Design Of An Very High Efficiency Evaporatively Cooled Mini-Split Air Conditioner, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

An in-house research project at the Florida Solar Energy Center in 2013 was conducted to evaluate the potential of an evaporatively cooled mini-split heat pump. The mini-split heat pump modified was a 1.5-ton Fujitsu model with 19.2 SEER and 10.0 HSPF energy efficiency ratings. Cooling capacity of the system is variable and ranges from 7,000 to 23,000 Btu/h.

We demonstrated that it is possible to improve the energy efficiency of the evaluated mini-split air conditioner by 21% seasonally in Florida's humid climate using an evaporative pre-cooler. Further, we showed the same apparatus was able to improve air conditioner efficiency by …

Anthem Sustainability Project, James Askegren, David Coleman, Luis Morgan

Capstone Design Expo Posters

Data centers are multiplying in number and size as electronic business, communication, collaboration, and recreation continue to increase in popularity. A large amount of electrical power consumed by data center computing equipment is converted to heat, requiring dedicated cooling systems 24 hours a day. Some data center operators have begun taking advantage of this heat instead of expelling it to the atmosphere. This approach not only reduces the electricity costs of these facilities but also minimizes the environmental impact they generate. Anthem has a 2.5 MW data center for which they would like to develop an air-to-air thermal recycle method. …

Evaluating The Performance Of Passive Chilled Beams With Respect To Energy Efficiency And Thermal Comfort, Janghyun Kim

Open Access Dissertations

Existing modeling approaches for passive chilled beams determined from tests on individual chilled beams in a laboratory are not adequate for assessing overall energy usage and occupant comfort within building simulation programs. In addition, design guidelines for passive chilled beam systems are needed for identifying appropriate applications and optimal configurations. This thesis includes (i) extensive experimental studies for characterizing the performance of passive chilled beams, in both laboratory settings and in field studies, (ii) development of passive chilled beam performance prediction models, (iii) integration of these models into building simulation models/tools and (iv) use of building simulation for overall assessment …

Parameter Estimation For Hvac System Models From Standard Test Data, Hannah Luthman

Boise State University Theses and Dissertations

Nearly all cooling systems, and an increasing proportion of heating systems, utilize the vapor compression cycle (VCC) to provide and remove heat from conditioned spaces. Even though the application of VCC’s throughout the building environment is ubiquitous, effective and accessible models of the performance of these systems remains elusive. Such models could be important tools for VCC designers, building designers and building energy managers as well as those who are attempting to optimize building energy performance through the use of model-based control systems.

Strides have been made in developing lumped parameter models for VCC’s. In spite of these contributions, widespread …

Solar Cal Poly Active Hvac Project, James Cornish, Jake Cosmo, Patrick Weston

Mechanical Engineering

For this project, the goal was to conceptualize, design, test, and implement an active HVAC system to be used in the Solar Cal Poly house competing in the Department of Energy’s 2015 Solar Decathlon. With many house iterations, it was decided to use a split system with an outdoor heat pump and indoor air handler, paired with a HRV for ventilation. Through system modeling using Design Builder and Energy Pro 6.5, the cooling load of the house was determined along with the cooling schedule. The foreseen safety precautions and limited construction time guided the entire project, along with the active …

Solar Evaporative Fan Coil Unit, Samuel Budnick, Kyle Kluever, Jeremy Dickson

Mechanical Engineering and Technology Senior Projects

The purpose of any engineering project is to anticipate a need and meet that need through prediction analysis and design. Over 70% of the nation’s energy is consumed by building infrastructure such as HVAC systems, electrical, etc. HVAC systems use boilers to generate hot water or steam to heat buildings and evaporative chillers to provide air conditioning, much like the central plant here on campus. The project included the construction of a solar collector that will heat water to 140F in order to run it through a heat exchanger that can have air passed over it. An evaporative chiller was …

Solar Evaporative Fan Coil Unit, Kyle Kluever, Samuel Budnick, Jeremy Dickson

Mechanical Engineering and Technology Senior Projects

The purpose of any engineering project is to anticipate a need and meet that need through prediction analysis and design. Over 70% of the nation’s energy is consumed by building infrastructure such as HVAC systems, electrical, etc. HVAC systems use boilers to generate hot water or steam to heat buildings and evaporative chillers to provide air conditioning, much like the central plant on campus. The project included the construction of a solar collector that will heat water to 140F in order to run it through a heat exchanger that can have air passed over it. An evaporative chiller was also …

Solar Evaporative Fan Coil Unit, Jeremy Dickson, Sam Budnick, Kyle Kluever

Mechanical Engineering and Technology Senior Projects

The purpose of any engineering project is to anticipate a need and meet that need through prediction analysis and design. Over 70% of the nation’s energy is consumed by building infrastructure such as HVAC systems, electrical, etc. HVAC systems use boilers to generate hot water or steam to heat buildings and chillers to provide cold water for cooling. The overall solar evaporative fan coil unit project involves the design and construction of a system that will heat and cool air using a solar collector and an evaporative chiller. This report covers the design and construction of the evaporative chiller specifically. …

Investigation Of Distributed Model Predictive Control For Economic Load Shifting In Building Hvac Systems, Peter Kinsella

Theses and Dissertations

One of the major challenges that building owners and operators face is maintaining a low cost of operation. In certain markets within the U.S., electrical cost varies throughout the day; it is higher during times of peak demand. This leaves the customer the incentive to cut back electrical use during peak demand periods. Since 40% of the peak electrical demand is due to the operation of the building HVAC system alone, the opportunity exists for shifting the building cooling load to off-peak hours. This can be done by pre-cooling the space, thereby using the building mass as a sort of …

Net Zero Residential Design For Solar Calpoly, Bryce Reiko Willis

Master's Theses

The Department of Energy (DOE) confirmed Team Solar Cal Poly from California Polytechnic State University, San Luis Obispo, as a competitor in the 2015 Solar Decathlon in February 2014. The Solar Decathlon is a biennial collegiate competition to construct a net-zero home and operate it for a week of “normal use”. Solar Cal Poly needed assistance with passive and active HVAC systems for the design, and thermal load models. The competition will take place in Irvine, CA [33.67⁰, 117.82⁰ W] from September 27 – October 3, 2015. After the completion, a potential final location for the house will be Santa …

Investigation Of Potential Benefits Of Revising Exception 1 Under Florida Building Code, Energy Conservation, Section 101.4.7.1.1 Duct Sealing Upon Equipment Replacement, Florida Solar Energy Center, Janet Mcilvaine

FSEC Energy Research Center®

Section 101.4.7.1.1, Duct sealing upon equipment replacement (Mandatory), of the 2012 Supplement to the Florida Building Code, Energy Conservation went into effect briefly in 2013. The new section required sealing of accessible ducts at the time of HVAC equipment replacement. Exception #1 however, eliminates the requirement for ducts in conditioned space, and by doing so, effectively eliminates the sealing requirement for building cavities in conditioned space that are used as air distribution paths. However, test results show that these building cavities are often connected to adjacent unconditioned spaces, in effect they are not really in the conditioned space because they …