Comparison of co-simulation approaches for building and HVAC/R system simulation

Appraisal of modern performance-based energy codes, as well as heating, ventilation, airconditioning and refrigeration (HVAC/R) system*design require use of an integrated building and system performance simulation program. However, the required scope of the modeling library of such integrated tools often goes beyond those offered in available simulation programs. One remedy for this situation would be to develop the required models in an existing simulation program.

Development and application of test cases for comparing vertical ground heat exchanger models

The main objective of this paper is to establish a set of test cases for analytical verifications and intermodel comparisons of ground heat exchanger (GHX) models used in building simulation programs. Several test cases are suggested. They range from steady-state heat rejection in a single borehole to varying hourly loads with large yearly thermal imbalance in multiple borehole configurations.

Use of simulation tools for managing buildings energy demand

There are several ways to attempt to model a building and its heat gains from external sources as well as internal ones in order to evaluate a proper operation and also audit retrofits actions. These models apply various techniques varying from simple regression to more physically grounded models.

Uncertainty and sensitivity analysis for detailed design support

Nowadays, building performance simulation (BPS) is still primarily used for code compliance checking in the Netherlands whilst it could provide the user already useful design information by e.g. indicating design solutions or introducing uncertainty analysis (UA) and sensitivity analysis (SA). This paper summarizes results from an ongoing research introducing UA and SA in BPS. A case study is performed based on a hypothetical building which is part of an international test method for assessing the accuracy of BPS tools with respect to various building performance parameters.

Towards a digital representation of physical phenomena to assess comfort in future environments

This paper presents the concept and a test implementation of a digital representation of the physical world designed to assess comfort quality in future environments. An integrated set of physical phenomena is modeled three-dimensionally to investigate the dynamic behavior of design objects holistically. The formulation supports the integration of computational simulation in the performance-based design process. It employs the principles of geometrical and physical selfcontainedness to avoid that complex geometrical and physical circumstances have to be specified at design time.

A New Model to Calculate the Drying of Concrete

The paper presents the theory for a design tool to calculate drying of concrete, from green condition to flooring. The degree of hydration, the cement ratio of the concrete, the temperature and the moisture state are taken into account. The moisture calculations are based on the use of Kirchhoff potentials. Calculation examples and comparison with experiments are also given in the paper.

Numerical evaluation on floor cooling capacity in an airport

In the modern architectural design, large space open area is widely used, for example, atrium, airport, open office, etc. Radiation heat transfer provides better indoor thermal comfort and makes it possible to apply high temperature cooling and low temperature heating. This will lead to high energy efficiency. Water carrying radiation systems, e.g. cooling ceiling and floor heating system, become an applicable solution for a good indoor climate design. The floor cooling is less effective than floor heating and can provide usually limited cooling capacity.

Natural convection heat transfer within vertically eccentric domed skylights cavities

Domed skylights are important architectural design elements to deliver daylight and solar heat into buildings and connect building’s occupants to outdoor. However, most of building energy simulation programs do not cover such skylights to quantify their energy performance when installed in buildings. This paper presents a numerical study on natural laminar convection within vertically eccentric domed cavities when heated from the exterior surface. Both interior and exterior surfaces are held at uniform temperatures.

Sensor-based information modeling for life cycle commissioning of residential buildings

According to the National Institute of Building Science (2006), one of the main goals of building commissioning is to “maintain facility performance across its life cycle”. In recent years, the maturing of sensing technology has helped to advance this vision through sensor-assisted building commissioning.

Short-term prediction of weather parameters using online weather forecasts

While people need to know tomorrow’s weather to decide suitable activities and precautions, so do the “intelligent” building management systems. The accuracy of the short-term prediction of the ambient conditions is particularly import for the development  of predictive control strategies.

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