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Full-Text Articles in Mechanical Engineering
Hydrogen And Syngas Production From Gasification Of Lignocellulosic Biomass In Supercritical Water Media, Jun-Ki Choi, Abtin Ataei, Ahmad Tavasoli, Farid Safari
Hydrogen And Syngas Production From Gasification Of Lignocellulosic Biomass In Supercritical Water Media, Jun-Ki Choi, Abtin Ataei, Ahmad Tavasoli, Farid Safari
Mechanical and Aerospace Engineering Faculty Publications
Novel biomass-processing technologies have been recently used for conversion of organic wastes into valuable biofuels like bio-hydrogen. Agricultural wastes are available and renewable energy resources to supply energy demand of the future. The purpose of this study is to investigate the production of hydrogen-rich syngas from wheat straw, walnut shell, and almond shell.
Simulating Energy Efficient Control Of Multiple-Compressor Compressed Air Systems, Sean Murphy, J. Kelly Kissock
Simulating Energy Efficient Control Of Multiple-Compressor Compressed Air Systems, Sean Murphy, J. Kelly Kissock
Mechanical and Aerospace Engineering Faculty Publications
In many industrial facilities it is common for more than one air compressor to be operating simultaneously to meet the compressed air demand. The individual compressor set-points and how these compressors interact and respond to the facility demand have a significant impact on the compressed air system total power consumption and efficiency. In the past, compressors were staged by cascading the pressure band of each compressor in the system. Modern automatic sequencers now allow more intelligent and efficient staging of air compressors.
AirSim, a compressed air simulation tool, is now able to simulate multiple-compressor systems with pressure band and automatic …
Understanding Industrial Energy Use Through Lean Energy Analysis, Brian Abels, Franc Server, J. Kelly Kissock, Dawit Ayele
Understanding Industrial Energy Use Through Lean Energy Analysis, Brian Abels, Franc Server, J. Kelly Kissock, Dawit Ayele
Mechanical and Aerospace Engineering Faculty Publications
Due to rising energy costs and global climate change, many industries seek to improve their energy efficiency. This paper describes a three-step method to analyze utility billing, weather, and production data to understand a company’s energy performance over time. The method uses regression modeling of utility billing data against weather and production data. The regression models are then driven with typical weather and production data to calculate the ‘normal annual consumption’, NAC. These steps are repeated on sequential sets of 12 months of data to generate a series of ‘sliding’ NACs and regression coefficients. The method can quantify successful energy …
Measuring Progress With Normalized Energy Intensity, Nathan Lammers, J. Kelly Kissock, Brian Abels, Franc Server
Measuring Progress With Normalized Energy Intensity, Nathan Lammers, J. Kelly Kissock, Brian Abels, Franc Server
Mechanical and Aerospace Engineering Faculty Publications
Energy standard ISO 50001 will require industries to quantify improvement in energy intensity to qualify for certification. This paper describes a four-step method to analyze utility billing, weather, and production data to quantify a company's normalized energy intensity over time. The method uses 3-pararameter change-point regression modeling of utility billing data against weather and production data to derive energy signature equations. The energy signature equation is driven by typical weather and production data to calculate the 'normal annual consumption', NAC, and divided by typical production to calculate 'normalized energy intensity' NEI. These steps are repeated on sequential sets of 12 …
Optimizing Compressed Air Storage For Energy Efficiency, Brian Abels, J. Kelly Kissock
Optimizing Compressed Air Storage For Energy Efficiency, Brian Abels, J. Kelly Kissock
Mechanical and Aerospace Engineering Faculty Publications
Compressed air storage is an important, but often misunderstood, component of compressed air systems. This paper discusses methods to properly size compressed air storage in load-unload systems to avoid short cycling and reduce system energy use. First, key equations relating storage, pressure, and compressed air flow are derived using fundamental thermodynamic relations. Next, these relations are used to calculate the relation between volume of storage and cycle time in load-unload compressors. It is shown that cycle time is minimized when compressed air demand is 50% of compressor capacity. The effect of pressure drop between compressor system and storage on cycle …
Improving Compressed Air Energy Efficiency In Automotive Plants: Practical Examples And Implementation, Nasr Alkadi, J. Kelly Kissock
Improving Compressed Air Energy Efficiency In Automotive Plants: Practical Examples And Implementation, Nasr Alkadi, J. Kelly Kissock
Mechanical and Aerospace Engineering Faculty Publications
The automotive industry is the largest industry in the United States in terms of the dollar value of production [1]. U.S. automakers face tremendous pressure from foreign competitors, which have an increasing manufacturing presence in this country. The Big Three North American Original Equipment Manufacturers (OEMs)-General Motors, Ford, and Chrysler-are reacting to declining sales figures and economic strain by working more efficiently and seeking out opportunities to reduce production costs without negatively affecting the production volume or the quality of the product. Successful, cost-effective investment and implementation of the energy efficiency technologies and practices meet the challenge of maintaining the …
American Electric Power, Jun-Ki Choi, Bhavik R. Bakshi
American Electric Power, Jun-Ki Choi, Bhavik R. Bakshi
Mechanical and Aerospace Engineering Faculty Publications
The Encyclopedia of Global Warming and Climate Change helps readers learn about the astonishingly intricate processes that make ours the only planet known to be habitable. These three volumes include more than 750 articles that explore major topics related to global warming and climate change—ranging geographically from the North Pole to the South Pole, and thematically from social effects to scientific causes.
Carbon Permits, Jun-Ki Choi, Bhavik R. Bakshi
Carbon Permits, Jun-Ki Choi, Bhavik R. Bakshi
Mechanical and Aerospace Engineering Faculty Publications
The Encyclopedia of Global Warming and Climate Change helps readers learn about the astonishingly intricate processes that make ours the only planet known to be habitable. These three volumes include more than 750 articles that explore major topics related to global warming and climate change—ranging geographically from the North Pole to the South Pole, and thematically from social effects to scientific causes.
Attribution Of Global Warming, Jun-Ki Choi, Bhavik R. Bakshi
Attribution Of Global Warming, Jun-Ki Choi, Bhavik R. Bakshi
Mechanical and Aerospace Engineering Faculty Publications
The Encyclopedia of Global Warming and Climate Change helps readers learn about the astonishingly intricate processes that make ours the only planet known to be habitable. These three volumes include more than 750 articles that explore major topics related to global warming and climate change—ranging geographically from the North Pole to the South Pole, and thematically from social effects to scientific causes.
Energy Efficient Process Heating: Managing Air Flow, Kevin Carpenter, J. Kelly Kissock
Energy Efficient Process Heating: Managing Air Flow, Kevin Carpenter, J. Kelly Kissock
Mechanical and Aerospace Engineering Faculty Publications
Much energy is lost through excess air flow in and out of process heating equipment. Energy saving opportunities from managing air flow include minimizing combustion air, preheating combustion air, minimizing ventilation air, and reconfiguring openings to reduce leakage.
This paper identifies these opportunities and presents methods to quantify potential energy savings from implementing these energy-savings measures. Case study examples are used to demonstrate the methods and the potential energy savings.The method for calculating savings from minimizing combustion air accounts for improvement in efficiency from increased combustion temperature and decreased combustion gas mass flow rate.
The method for calculating savings from …
Measuring Plant-Wide Energy Savings, J. Kelly Kissock, Carl Eger
Measuring Plant-Wide Energy Savings, J. Kelly Kissock, Carl Eger
Mechanical and Aerospace Engineering Faculty Publications
This paper presents a general method for measuring plant-wide industrial energy savings and demonstrates the method using a case study from an actual industrial energy assessment. The method uses regression models to characterize baseline energy use. It takes into account changes in weather and production, and can use sub-metered data or whole plant utility billing data. In addition to calculating overall savings, the method is also able to disaggregate savings into components, which provides additional insight into the effectiveness of the individual savings measures.
Although the method incorporates search techniques and multi-variable least-squares regression, it is easily implemented using data …
Quantifying Savings From Improved Boiler Operation, Kevin Carpenter, J. Kelly Kissock
Quantifying Savings From Improved Boiler Operation, Kevin Carpenter, J. Kelly Kissock
Mechanical and Aerospace Engineering Faculty Publications
On/off operation and excess combustion air reduce boiler energy efficiency. This paper presents methods to quantify energy savings from switching to modulation control mode and reducing excess air in natural gas fired boilers.
The methods include calculation of combustion temperature, calculation of the relationship between internal convection coefficient and gas flow rate, and calculation of overall heat transfer assuming a parallel-flow heat exchanger model. The method for estimating savings from changing from on/off to modulation control accounts for purge and drift losses through the boiler and the improved heat transfer within the boiler due to the reduced combustion gas flow …
Lean Energy Analysis: Identifying, Discovering And Tracking Energy Savings Potential, J. Kelly Kissock, John Seryak
Lean Energy Analysis: Identifying, Discovering And Tracking Energy Savings Potential, J. Kelly Kissock, John Seryak
Mechanical and Aerospace Engineering Faculty Publications
Energy in manufacturing facilities is used for direct production of goods, space conditioning, and general facility support such as lighting. This paper presents a methodology, called lean energy analysis, LEA, for graphically and statistically analyzing plant energy use in terms of these major end uses.
The LEA methodology uses as few as 60 easily obtainable data points. Multivariable change-point models of electricity and natural gas use as functions of outdoor air temperature and production data are developed. The statistical models are used to subdivide plant energy use into facility, space-conditioning and production-related components.
These breakdowns suggest the savings potential from …
Estimating Energy Savings In Compressed Air Systems, Chris Schmidt, J. Kelly Kissock
Estimating Energy Savings In Compressed Air Systems, Chris Schmidt, J. Kelly Kissock
Mechanical and Aerospace Engineering Faculty Publications
Compressed air is typically one of the most expensive utilities in an industrial facility. As a result, potential savings opportunities are aggressively sought out and identified. Once identified, projected energy savings must be calculated in order to justify the cost of implementing the savings opportunity. It is important to calculate projected energy and cost savings as accurately as possible. Unfortunately, savings are frequently overestimated because the methods used to estimate savings neglect to consider important factors such as compressor control and type, storage, and multiple compressor operation.
In this paper, a methodology is presented for modeling air compressor performance and …