A novel TRNSYS type for short-term borehole heat exchanger simulation: B2G model

Models of ground source heat pump (GSHP) systems are used as an aid for the correct design and optimization of the system. For this purpose, it is necessary to develop models which correctly reproduce the dynamic thermal behavior of each component in a short-term basis. Since the borehole heat exchanger (BHE) is one of the main components, special attention should be paid to ensuring a good accuracy on the prediction of the short-term response of the boreholes. The BHE models found in literature which are suitable for short-term simulations usually present high computational costs. In this work, a novel TRNSYS type implementing a borehole-to-ground (B2G) model, developed for modeling the short-term dynamic performance of a BHE with low computational cost, is presented. The model has been validated against experimental data from a GSHP system located at Universitat Politècnica de València, Spain. Validation results show the ability of the model to reproduce the short-term behavior of the borehole, both for a step-test and under normal operating conditions.

Coupling short-term (B2G model) and long-term (g-function) models for ground source heat exchanger simulation in TRNSYS. Application in a real installation

Ground-source heat pump (GSHP) systems represent one of the most promising techniques for heating and cooling in buildings. These systems use the ground as a heat source/sink, allowing a better efficiency thanks to the low variations of the ground temperature along the seasons. The ground-source heat exchanger (GSHE) then becomes a key component for optimizing the overall performance of the system. Moreover, the short-term response related to the dynamic behaviour of the GSHE is a crucial aspect, especially from a regulation criteria perspective in on/off controlled GSHP systems. In this context, a novel numerical GSHE model has been developed at the Instituto de Ingeniería Energética, Universitat Politècnica de València. Based on the decoupling of the short-term and the long-term response of the GSHE, the novel model allows the use of faster and more precise models on both sides. In particular, the short-term model considered is the B2G model, developed and validated in previous research works conducted at the Instituto de Ingeniería Energética. For the long-term, the g-function model was selected, since it is a previously validated and widely used model, and presents some interesting features that are useful for its combination with the B2G model. The aim of the present paper is to describe the procedure of combining these two models in order to obtain a unique complete GSHE model for both short- and long-term simulation. The resulting model is then validated against experimental data from a real GSHP installation.

Single-crystal Raman spectroscopy of natural schafarzikite FeSb2O4 from Pernek, Slovak Republic

The single crystal Raman spectra of natural mineral schafarzikite FeSb2O4 from the Pernek locality of the Slovak Republic are presented for the first time. Raman spectra of natural mineral apuanite Fe2+Fe43+Sb4O12S, originating from the Apuan Alps in Italy, as well as spectra of synthetic ZnSb2O4 and arsenite mineral trippkeite CuAs2O4 are also presented for the first time. The spectra of the antimonite minerals are characterized by a strong band in the region 660 – 680 cm-1 with shoulders on either side, and a band of medium intensity near 300 cm-1. The spectrum of the arsenite mineral is characterized by a medium band near 780 cm-1 with a shoulder on the high wavenumber side and a strong band at 370 cm-1. Assignments are proposed based on the spectral comparison between the compounds, symmetry modes of the bands and prior literature. The single crystal spectra of schafarzikite showed good mode separation, allowing bands to be assigned a symmetry species of A1g, B1g, B2g or Eg.

Organizational factors in the diffusion of an industry standard: implementing an online documentation system for Australian exporters

At present, governments in many countries are actively engaged in the development of electronic trading and certification standards to enable the smooth operation of export markets. Standards and their usability underpin confidence in the operations of markets and their effective functioning. In institutional markets, an important role for government agencies lies in developing the initial specifications for standards for interoperable systems. Once these specifications are accepted, governments can then facilitate the eventual diffusion of a standard to the B2B marketplace. Acceptance of an industry standard can determine demand, which defines the viability of that market. In this paper, we describe an initiative by a government agency, the Australian Quarantine and Inspection Service (AQIS), in developing EXDOC, a standard for export documentation and the role that AQIS played in its implementation and diffusion. Our case study illustrates a successfully facilitated B2G implementation. It demonstrates how a standard can be supported and promulgated for the effective functioning of markets in the transition from manual to online export documentation. Once the overarching specifications for related industries have been established and diffused by government, opportunities arise for private sector markets to develop across these industries. Government agencies can promote the effective operation of standards for electronic markets. The EXDOC implementation and its iterations provide an exemplar of active engagement in the development of electronic trading and certification standards for an institutional market. Its successful diffusion provides a model of the implementation process for other export sectors and agencies.

Conflicting expectations in transforming government service processes: the story of e-payment for social welfare in Ireland

Despite its clear potential and attractiveness as a solution to a broad range of societal problems, E-Government has not been adopted to levels predicted in early 2000 literature. Whilst case studies of punctual development of E-Government initiatives abound, few countries have progressed to high levels of maturity in the systematic use of ICT in the relationship between government and citizens. At the same time, the current period brings challenges in terms of access to public services and costs of delivering these services which make the large scale use of ICT by governments more attractive than ever, if not even a necessity. This paper presents a detailed case study of a specific E-Government initiative in Ireland in the area of E-payments for G2C, in the social welfare area. Locating the current initiative in its historical context, it analyses the varied motivations and conflicting requirements of the numerous stakeholders and discusses the constraints that bear on the potential scenarios that could be followed at this point in time.