Heat Transfer, Combustion Commons^™

Studying The Influential Parameters Of An Office Building’S Energy Consumption In North America, Naveen Raghava Krishnan Bhoopal

Major Papers

The study of building energy consumption has gained immense significance in recent times due to the burgeoning global population and the rapid depletion of energy resources. The present research focuses on analyzing individual parameters that impact building energy usage and devising methods and strategies to reduce energy consumption. An existing office building in Philadelphia was chosen as a reference for simulation in TRNSYS. The factors that affect the building, such as ambient temperature, solar radiation, building envelope, wind speed, and internal gains, were studied and defined according to the existing building standards. Predictive modeling is performed with these inputs for …

Accomplishments Of Endwall Contouring On Heat Transfer In A Passage Of A Turbine Blade, Kozhikkatil Sunil Arjun, Tide Porathoor Sunny, Narayanan Biju

Makara Journal of Technology

The study explores axisymmetric endwall contouring with emphasis on the design of novel endwalls capable of heat load reduction. Optimizations with parameterization numerically determined by the endwall of flat shape led to the endwall of the contoured shape with substantial depletion of heat transfer in the passage of the vane. Heat transfer attributes for the generated contoured endwalls were analyzed for the exit Reynolds number of 2 × 106 . Endwall three-dimensional contouring resulted in remarkable changes in secondary flow vortices, jet-to-secondary flow interaction, and film cooling effectiveness on the flat endwall. The results pointed out that the axisymmetric convergent …

Experimental Analysis On Effects Of Inclination And Direction On Supercritical Carbon Dioxide Heat Transfer For Internal Pipe Flow, Emmanuel Gabriel-Ohanu

Electronic Theses and Dissertations, 2020-

Supercritical carbon dioxide (sCO2) can be utilized as a working or heat transfer fluid in various thermal systems with applications in large-scale power cycles; portable power production units, coolant systems and devices. However, there are no sufficient methods and equations of heat transfer coefficient correlations, and in addition insufficient research studies about the mechanisms controlling heat transfer processes for sCO2. This study is motivated by the need to understand the intricate properties of sCO2 heat transfer and fluid dynamics with an emphasis on flow direction and inclination effects. This paper presents the study on effects of gravity, buoyancy on sCO2 …

Heat Pump Integrated Thermal Storage For Building Demand Response And Decarbonization, Sara Sultan

Doctoral Dissertations

This work presents a novel thermal energy storage (TES) integrated with existing residential heat pump (HP). The research focuses on controls and configuration for energy, demand, cost and carbon emissions savings for residential buildings’ energy consumption. This work will be significant in developing a framework especially for reduced energy demand and carbon emissions associated with space heating and cooling in residential buildings. Since buildings account for about 40% primary energy consumption in U.S. and half of that is associated with HP.

An existing air source HP in integrated with a phase change material (PCM) based TES via active configuration where …

Applications Of Large Eddy Simulations To Novel Internal Combustion Concepts, Patrick O'Donnell

All Dissertations

Computational fluid dynamics (CFD) simulations of internal combustion engines (ICEs) are becoming an increasingly popular tool in the automotive industry to either explain experimentally observed trends or perform lower cost design iterations. The convenience of commercially available CFD software and advancements made in computing hardware have been the impetus behind this growing popularity. However, obtaining accurate results using these software packages is not a trivial process and requires an in-depth understanding of the underlying numerical methodology and sub models for various physical phenomena. Specific to the ICEs, CFD simulation often entails the use of models for detailed chemistry and combustion, …

Transient Thermal Performance Enhancement Of Phase Change Materials Through Novel Pin Arrangements Under Varied Gravity Conditions, Junaid Khan

Masters Theses

This thesis presents a comprehensive examination of encapsulation techniques and performance enhancement strategies for Phase Change Materials (PCMs) in the thermal management of spacecraft avionics. This research contributes to optimizing PCM applications in spacecraft through historical analysis, transient thermal performance enhancement, and computational studies.

The first chapter explains the significance of PCMs in passive thermal management since the beginning of space-age technology, it underlines the low thermal conductivity of PCMs and the necessity of incorporating materials with high thermal conductivity, such as metal foams, to improve heat transfer. It also discusses various advancements in PCM research for spacecraft thermal management …

Performance And Emissions Study Of N+3 And N+4 Engine Models With Several Fuel Types Using Npss, Abel Solomon

McKelvey School of Engineering Theses & Dissertations

The aviation industry is known to be one of the major contributors to greenhouse gases accounting for 4.9% of the global greenhouse emissions. With the ever-increasing threat of climate change to the overall survival of the planet, the exploration of new technologies and alternative energy sources that minimize greenhouse gas emissions are of paramount importance. In this regard, the development of propulsion systems well suited for the performance and emissions requirements of future commercial aircraft plays a crucial role. This thesis investigates N+3 and N+4 technology-level propulsion systems that are proposed by NASA as possible propulsion systems for advanced single-aisle …

Measurement Of Conduction, Radiation, And Convection Thermal Energy To Assess Baking Performance In Residential Ovens., Sean Simpson

Electronic Theses and Dissertations

Residential ovens are complicated thermal environments capable of delivering convection, conduction, and radiation heat transfer to food. The amount and mode of heat transfer can change based on the design of the oven cavity, cooling systems, and oven cycle algorithms. Studies have shown that the changes in one heat transfer mode can have an impact on the quality of baked goods. The many variables involved make designing residential ovens a time consuming and costly process. The goal of this study is to adapt thermal energy sensing technology to collect energy data from a residential oven and develop correlations to quality …

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. …

Experimental Investigation Of The Phase Change Process Within Circular Geometries, Kyle Teather

Electronic Thesis and Dissertation Repository

Latent heat thermal energy storage systems have many advantages over sensible-heat-based thermal storage systems, such as an increased energy density with a narrower range of operating temperatures. The main barrier to implementing latent heat storage systems is the low thermal conductivity of typical storage materials, called phase change materials (PCMs). Furthermore, the heat transfer mode in the liquid phase is natural convection, which is influenced by the geometry and orientation of the heat source and sink, thus impacting the phase change pattern and heat transfer. It is critical to have a good understanding of the underlying fundamental physics over the …

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 …

Addressing Low Heat Pump Heating System Sales In The Uk, Ben Costelloe

Articles

The replacement of existing fossil fuel boilers with heat pumps is seen as a key measure in the decarbonisation of heating systems and addressing climate change. This policy however, is currently failing in many Western European states, particularly in the UK. The many reasons for this situation are examined. However, the age of UK housing stock and particularly the high number of dwellings built prior to the introduction of building insulation regulations in 1980, are key. To maintain the running cost of air source heat pumps competitive with those of the gas boilers they generally replace the heat pump lift …

Flat Plate Solar Collector For A Tiny Home, Clarice Leslie Nicholas

Honors Projects

Pallet Shelter is a company that builds tiny houses for the homeless. We partnered with them to build a solar water heater for their homes so that their tenants can have hot running water. The collector panel sits on the roof of the shelter and absorbs the energy of the sun and uses it to heat water flowing through an array of copper pipes. The hot water is then stored in an insulated tank inside the shelter.

Cooled Liquid Rocket Thrust Chamber, Benjamin Gibson, Kealan Frederick Harris, Ryan Frank Schackel, Bjorn Thorsen

Mechanical Engineering

Cooling may affect the thrust output of a small-scale rocket. Little research is published about small-scale rocket performance. We hypothesize the thrust produced varies as the amount of cooling varies. To facilitate assessing this hypothesis, we have designed and built a liquid rocket engine rated for at approximately 25 lb_f of thrust. Our objective was to build in parallel with Cal Poly Space Systems, who built a rocket engine with similar specifications except without cooling. Our challenge is to integrate film cooling, so that the effects of cooling may be compared to Cal Poly Space System’s engine which has …

Flexible Water Cooling, Joshua Terlaje, Andrew Lin, Nicholas Morales, Tanner Parrott

Mechanical Engineering

The goal of this project is to develop and deploy a water-cooling system to reduce the danger of heat exhaustion among communities of farmworkers. Currently, it is difficult to keep chilled water available throughout the workday when using portable water coolers. The idea uses a refrigeration system to chill the water supply by using the power take-off (PTO) on farm equipment and a corresponding generator to get around this restriction.

The project places a strong premium on keeping the chilled water supply at a maximum temperature of 59°F to ensure compliance with the California Department of Industrial Relations' requirements. Each …

Thermal Transport And Physical Characteristics Of Silver-Reinforced Biodegradable Nanolubricant, Jaime Taha-Tijerina, Karla Aviña, Nicolás Antonio Ulloa-Castillo, Dulce Viridiana Melo-Maximo

Informatics and Engineering Systems Faculty Publications and Presentations

In this investigation, the thermal transport behavior of biodegradable lubricant reinforced with silver nanostructures (AgNs) at various filler fractions of 0.01, 0.05, 0.10, and 0.20 weight percent was evaluated over a temperature scan analysis, ranging from room temperature up to 60 °C. The experimental results revealed significant gradual enhancements in thermal conductivity as AgNs concentration and evaluating temperatures were increased. These improvements showed the important role of nanostructures’ interaction within the biodegradable lubricant. The thermal conductivity performance improved for nanolubricants ranging from 6.5% at 30 °C and 0.20 wt.% AgNs content up to a maximum 32.2%, which was obtained at …

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 …

Efficient Sintering Of Lunar Soil Using Concentrated Sunlight, Diprajit Biswas

Electronic Theses and Dissertations

Construction material is one crucial need for long-term habitation on the moon. When concentrated for high heat flux, solar radiation can heat lunar soil or regolith until it sinters at temperatures above 900°C. The solid, sintered soil simulant can be used as construction material. This work explores the conditions leading to effective lunar soil sintering for both direct and indirect irradiated sintering. Lunar soil simulants were sintered using concentrated light from a xenon-arc lamp with varying heat flux intensity. During direct sintering of LHS-1, a sintering range of 860°C-1140°C corresponding to a peak heat flux of 105-120 kW/m2 was identified …

Classification Of Electrical Current Used In Electroplastic Forming, Tyler Grimm

All Dissertations

Electrically assisted manufacturing (EAM) is the direct application of an electric current to a workpiece during manufacturing. This advanced manufacturing process has been shown to produce anomalous effects which extend beyond the current state of modeling of thermal influences. These purported non-thermal effects have collectively been termed electroplastic effects (EPEs).

While there is a distinct difference in results between steady-state (ideal DC) testing and pulsed current testing, the very definition of these two EAM methods has not been well established. A "long" pulse may be considered DC current; a "short" pulse may produce electroplastic effects; and even "steady-state" current shapes …

A Systematic Study Into The Design And Utilization Of Burn Wire As A Means Of Tensioning And Releasing Spacecraft Mechanisms Through Applied Joule Heating, Chandler Dye

Mechanical Engineering Undergraduate Honors Theses

The joule heating characteristics of Nichrome burn wires, often used as a thermal cutting device in mechanisms designed to fasten and release CubeSat deployables, are examined in the following thesis. Wires ranging from 0.125 inches to 2 inches long, and diameters of 30 Ga and 40 Ga, are investigated through analytical calculations and thermal simulations based on heat transfer due to joule heating, and through physical circuitry-based experiments. The temperature data is used to generate heating curves to predict the time it takes for Nichrome wires to fail under varying testing parameters. This research aims to catalog a series of …