Henze G.P.,University of Colorado at Boulder |
Florita A.R.,University of Colorado at Boulder |
Brandemuehl M.J.,University of Colorado at Boulder |
Felsmann C.,TU Dresden |
Cheng H.,Taylor Engineering Inc.
Journal of Solar Energy Engineering, Transactions of the ASME | Year: 2010
Using a simulation and optimization environment, this paper presents advances toward near-optimal building thermal mass control derived from full factorial analyses of the important parameters influencing the passive thermal storage process for a range of buildings and climate/utility rate structure combinations. Guidelines for the application of, and expected savings from, building thermal mass control strategies that can be easily implemented and result in a significant reduction in building operating costs and peak electrical demand are sought. In response to the actual utility rates imposed in the investigated cities, fundamental insights and control simplifications are derived from those buildings deemed suitable candidates. The near-optimal strategies are derived from the optimal control trajectory, consisting of four variables, and then tested for effectiveness and validated with respect to uncertainty regarding building parameters and climate variations. Due to the overriding impact of the utility rate structure on both savings and control strategy, combined with the overwhelming diversity of utility rates offered to commercial building customers, this study cannot offer universally valid control guidelines. Nevertheless, a significant number of cases, i.e., combinations of buildings, weather, and utility rate structure, have been investigated, which offer both insights and recommendations for simplified control strategies. These guidelines represent a good starting point for experimentation with building thermal mass control for a substantial range of building types, equipments, climates, and utility rates. © 2010 by ASME.
Hydeman M.,Taylor Engineering Inc.
Consulting-Specifying Engineer | Year: 2010
Some of the significant issues that need to be considered to improve the accuracy of money sensors are discussed. A money sensor is defined as a sensor where a small error in accuracy can yield large changes in a client's utility bill. Economizers play a key role in establishing the accuracy of such a sensor. The objective of the economizer high-limit switch is to determine when it is beneficial to bring in external air than return air. There are three technologies available for such switches, such as temperature based, enthalpy based, and the H705A solid-state enthalpy controller from Honeywell used in smaller packaged units. These technologies need to be maintained and monitored properly to ensure that they are unable to have adverse impacts on these economizer switches. Another issue that can adversely impact the performance of an air-side economizer is the location of the outdoor sensor for the high-limit switch.
Bender C.,Taylor Engineering Inc. |
Smith J.M.,Engineer Research and Development Center |
Kennedy A.,University of Notre Dame |
Jensen R.,Engineer Research and Development Center
Coastal Engineering | Year: 2013
Hurricane Ike (2008), with its associated storm surge, caused extensive damage across parts of the northwestern Gulf Coast when it made landfall in the late hours of September 12, 2008 along the upper Texas coast at the upper end of Category 2 intensity. An extensive instrumentation effort allowed the collection of both nearshore and inland wave and water level data as Hurricane Ike passed the Louisiana coast and made landfall in Texas. This article presents the results of a validation effort for the STWAVE model and the bottom friction coefficients applied in the model with comparisons to the Hurricane Ike measured wave data. Examination of STWAVE model results as contour plots and time series of wave height and period; wave spectra at selected time steps and scatter plots of simulated versus modeled wave results allow evaluation of the model performance. STWAVE model results indicate good agreement with the measured nearshore wave data for an open water Manning 'n' bottom friction coefficient equal to 0.03s/m0.33. STWAVE model results indicate good agreement with the measured inshore wave data with Manning 'n' bottom friction coefficients equal to values derived from land classification data and applied in the ADCIRC model. © 2012 Elsevier B.V.
Ma Y.,2169 Etcheverry Hall |
Kelman A.,University of California at Berkeley |
Daly A.,Taylor Engineering Inc. |
Daly A.,United Environment & Energy, Llc |
Borrelli F.,University of California at Berkeley
IEEE Control Systems | Year: 2012
The building sector is the largest energy consumer in the world. Therefore, it is economically, socially, and environmentally significant to reduce the energy consumption of buildings. Achieving substantial energy reduction in buildings may require rethinking the whole processes of design, construction, and operation of a building. This article focuses on the specific issue of advanced control system design for energy efficient buildings. © 1991-2012 IEEE.
Liu X.,Taylor Engineering Inc. |
Kabiling M.B.,Taylor Engineering Inc. |
Bratos S.M.,U.S. Army
Ports 2013: Success Through Diversification - Proceedings of the 13th Triennial International Conference | Year: 2013
Jacksonville Harbor, already a major U.S. port, is presently undergoing a general reevaluation study by the U.S. Army Corps of Engineers-Jacksonville District (USACE-SAJ) that is evaluating various plans to deepen the navigation channel depth from its current depth of 40 feet (12.2 meters) to a maximum depth of 50 feet (15.24 meters) from the river mouth at the Atlantic Ocean to a point 14 miles (22.5 km). Deepening the existing channel would allow for larger vessels to access the Jacksonville Port, thereby reducing transportation costs and providing increased navigational safety while minimizing or avoiding negative impacts to environmental resources. To evaluate the potential impacts of a channel-deepening project on the St. Johns River estuary system, a three-dimensional hydrodynamic and transport model of Jacksonville Harbor was developed by using the Environmental Fluid Dynamic Code (EFDC) model. The EFDC hydrodynamic and salinity model, validated for the Jacksonville Harbor deepening project area, provided the means to assess the direct impacts of channel modifications to salinity and water circulation in the main stem of the lower St. Johns River from various channel-deepening scenarios during a 6-year evaluation period (1996-2001). The 6-year evaluation period includes the lowest river flow during any 3-year period in the river's 78-year flow record to ensure that assessed project impacts are greater than those during an average year. Therefore, this study's evaluation presents conservative estimates of the impacts of the channel deepening. The hydrodynamic model results examine the effects of proposed channel-deepening projects on water level, salinity and water age throughout the model domain and provides tools for analyses of biological, chemical, and ecological impacts. This paper presents the cumulative impacts in the future (50 years after the project completion) from proposed channel-deepening alternatives and other projects, including the Mayport Deepening Project for the U.S. Navy, freshwater withdrawals in the St. Johns River, and future sea level rise. © 2013 American Society of Civil Engineers.