Experiences with and interpretation of standard test methods of building energy analysis tools

The authors separately apply ANSI/ASHRAE Standard 140-2001 to the simulation program TRNSYS, comparing not only their results but the differences in their simulation assumptions and in their interpretations of the Standard's test cases. Results of the application are presented for all three authors, showing that there is a significant amount of leeway within a complex simulation tool such asTRNSYS for users of different backgrounds to apply their own common simulating practices and still fall comfortably within the range of acceptability specified by such Standards. Included in the application results are results of sensitivity tests that demonstrate the relative importance of assumption differences

Converging on a recommended set of interpretations and assumptions in applying standard tests to energy analysis tools

The authors, having individually applied ANSI/ASHRAE Standard 140-2001 to the simulation program TRNSYS in a previous project, compare their results, simulation assumptions, and interpretations of the Standard's test cases to arrive at a conformed set of recommended practices. Sensitivities to individual assumptions are investigated and results of applying the conformed set of assumptions are presented

Combining different validation techniques for continuous software improvement - Implications in the development of TRNSYS 16

Validation using published, high quality test suites can serve to identify different problems in simulation software: modeling and coding errors, missing features, frequent sources of user confusion. This paper discusses the application of different published validation procedures during the development of a new TRNSYS version: BESTEST/ASHRAE 140 (Building envelope), HVAC BESTEST (mechanical systems) and IEA ECBCS Annex 21 / SHC Task 12 empirical validation (performance of a test cell with a very simple mechanical system). It is shown that each validation suite has allowed to identify different types of problems. Those validation tools were also used to diagnose and fix some of the identified problems, and to assess the influence of code modifications. The paper also discusses some limitations of the selected validation tools

Free radical reactions of some transition and organotransition metal complexes

A general, nonspecialized method for producing superoxide ion in aqueous solution has been developed. The method is based upon photochemical generation of a reducing radical species and its subsequent reaction with dioxygen to produce O(,2)(\u27-). The product is identified as superoxide ion by comparison with the known UV spectrum of O(,2)(\u27-) and by measuring the rate of loss of the photolysis product. Factors affecting the yield of O(,2)(\u27-) are investigated. Optimal working conditions proved to be 5.0 M 2-propanol, 6.3 (mu)M Ph(,2)CO, dioxygen saturated at pH \u3e 11 with irradiation performed using a Hg arc lamp photoreactor. Nearly 400 (mu)M O(,2)(\u27-) is produced in 30 s under these conditions;The reactions of O(,2)(\u27-) with several cobalt(III) complexes and ferricinium ion proceed through an outer sphere electron transfer pathway. Second-order rate constants at 25.0(DEGREES)C are: 31.3, 23.8, and 16.4 M(\u27-1) s(\u27-1) for Co(NH(,3))(,6)(\u27+3), Co(en)(,3)(\u27+3), and Co(trans-1,2-cyclohexanediamine)(,3)(\u27+3), respectively, and 8.6 x 10(\u276) M(\u27-1) s(\u27-1) for Cp(,2)Fe(\u27+). For the Co(III) reactions, several physical (temperature, pH) and chemical (isotopic labeling of complex and solvent, choice of counter anion, presence of dioxygen) effects were investigated. Some observations, through use of the Marcus correlation, are made on the O(,2)(aq)/O(,2)(\u27-) electron self-exchange rate constant;The stoichiometry and kinetics of the reactions of bis(dimethyl- glyoximato)cobalt(II) complexes with polyhalomethanes are also reported. A two-step mechanism is supported by the data. The first and rate limiting step is halogen atom abstraction by the cobalt complex and formation of a free radical. The existence and reactivity of the latter is demonstrated through the use of the radical scavenging agent 4-hydroxy-2,2,6,6-tetramethylpiperidinooxy (4- HTMPO) in a kinetic competition mode. Numerical integration techniques were used to simulate data with various choices of competitive rate constants, permitting an estimation of the relative rate constants for the reaction of (.)CCl(,3) and 4-HTMPO vs. its reaction;with Co(dmgH)(,2)py in benzene. The ratio was found to be 1.8 (+OR-) 0.1 at 25.0(DEGREES)C; (\u271)DOE Report IS-T-1083. This work was performed under Contract No. W-7405-Eng-82 with the U.S. Department of Energy

Simulation synergy : expanding TRNSYS capabilities and usability

Developers of simulation packages are now able to take advantage of the increase in available desktop computing power to expand the capabilities and usability of their programs. This paper will illustrate these opportunities by discussing the different techniques the developers of the TRNSYS software package have used to try and create a synergy between TRNSYS and external programs and between the developers and users of the program

Concentrating Solar Power - Molten Salt Pump Development, Final Technical Report (Phase 1)

The purpose of this project is to develop a long shafted pump to operate at high temperatures for the purpose of producing energy with renewable resources. In Phase I of this three phase project we developed molten salt pump requirements, evaluated existing hardware designs for necessary modifications, developed a preliminary design of the pump concept, and developed refined cost estimates for Phase II and Phase III of the project. The decision has been made not to continue the project into Phases II and III. There is an ever increasing world-wide demand for sources of energy. With only a limited supply of fossil fuels, and with the costs to obtain and produce those fuels increasing, sources of renewable energy must be found. Currently, capturing the sun's energy is expensive compared to heritage fossil fuel energy production. However, there are government requirements on Industry to increase the amount of energy generated from renewable resources. The objective of this project is to design, build and test a long-shafted, molten salt pump. This is the type of pump necessary for a molten salt thermal storage system in a commercial-scale solar trough plant. This project is under the Department of Energy (DOE) Solar Energy Technologies Program, managed by the Office of Energy Efficiency and Renewable Energy. To reduce the levelized cost of energy (LCOE), and to meet the requirements of 'tomorrows' demand, technical innovations are needed. The DOE is committed to reducing the LCOE to 7-10 cents/kWh by 2015, and to 5-7 cents/kWh by 2020. To accomplish these goals, the performance envelope for commercial use of long-shafted molten salt pumps must be expanded. The intent of this project is to verify acceptable operation of pump components in the type of molten salt (thermal storage medium) used in commercial power plants today. Field testing will be necessary to verify the integrity of the pump design, and thus reduce the risk to industry. While the primary goal is to design a pump for a trough solar power plant system, the intent is for the design to be extensible to a solar power tower application. This can be accomplished by adding pumping stages to increase the discharge pressure to the levels necessary for a solar power tower application. This report incorporates all available conceptual design information completed for this project in Phase I

RURAL VIRGINIA: PROVIDING FOR THE FUTURE THROUGH CHANGING POLICY

Community/Rural/Urban Development,

A Future for Entertainment-Defense Research Collaboration

In 1997, the National Research Council (NRC) issued a report that specified a joint research agenda for defense and entertainment modeling and simulation. This report showed the excellent opportunities for synergy between the entertainment and defense industries. For years, they have been solving similar problems for very different application areas. While those two communities' opposing cultures have been difficult to reconcile, recent efforts have proven promising. The looming question is whether the military sector can follow the leaping technological pace in the entertainment sector. That pace indicates tremendous growth in the entertainment industry, which will be coupled with continued technological innovation. The article shows how those advances will be equally vital for future defense applications, thereby demonstrating the importance of continued and increased defense-entertainment collaboration.Army Research OfficeAssistant Secretary of the Army for Manpower and Reserve AffairsNational Reconnaissance Office, Advanced Network and ServicesNavy Modeling and Simulation Management Offic

Legal U.S. Immigration: Influences on Gender, Age, and Skill Composition

The authors develop empirical models that enable them to examine the influence of two important determinants - source country characteristics and U.S. immigration policy - on the gender, age, and skills of immigrants coming to America.https://research.upjohn.org/up_press/1064/thumbnail.jp