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Now showing items 21-30 of 49
Performance analysis of a single underground thermal storage borehole using phase change material
(International Ground Source Heat Pump Association, 2018)
Ground source heat pumps (GSHP) are used to provide both heating and cooling to a given system. These heat pumps transfer heat efficiently between the system and the ground. Despite this high efficiency, there has been a ...
Simulated temperature evolution of large BTES - case study from Finland
(International Ground Source Heat Pump Association, 2018)
The largest borehole thermal energy storage system in Finland (also one of the largest systems in Europe) is located in Sipoo, Southern Finland. The system produces heating and cooling energy for a large logistics centre ...
Video inspection of wells in open loop ground source heat pump systems in Norway
(International Ground Source Heat Pump Association, 2018)
This paper presents results from video inspections of groundwater wells in Melhus and Elverum, in Norway. The method has identified iron hydroxides, bacterial growth and sand production as causes of clogging in different ...
Extending the Ashrae Tp8 method for vertical borefield design to uniform BHE temperature boundary conditions
(International Ground Source Heat Pump Association, 2018)
The Ashrae method is a fast algorithm for calculating the overall length of closed-loop borehole heat exchangers, considering the ground thermal response and the building thermal load profile. The method includes a corrective ...
Virtual borehole for thermal response test unit calibration: Test facility and concept development
(International Ground Source Heat Pump Association, 2018)
Precise calculation of the borehole length requires good estimation of the ground thermal conductivity. In practice, the ground thermal conductivity is measured in-situ at a specific location using what is referred to as ...
Near-instant g-function construction with artificial neural networks
(International Ground Source Heat Pump Association, 2018)
A g-function is a useful tool that simplifies the calculations of heat exchanges in a ground-coupled heat pump system. In this work, we show how an artificial neural network can be trained to construct a g-function with ...
Development of a thermal conductivity map of Stockholm
(International Ground Source Heat Pump Association, 2018)
New methods have been suggested to spatially extend in situ thermal response test (TRT) assessments based on geostatistical analysis. These methods can be used to determine a stochastic distribution of the subsurface thermal ...
Model predictive control applied to residential self-assisted ground source heat pumps
(International Ground Source Heat Pump Association, 2018)
The seasonal performance and feasibility of a "self-assisted" ground source heat pump system are examined. The system uses an electric heating element to inject heat into the ground and reduce peak energy demand by eliminating ...
Thermal Response Test experiments and modelling applied to shallow geothermal piles of different geometry
(International Ground Source Heat Pump Association, 2018)
Geothermal piles are structural elements that encountered interest in ground source heat pump (GCHP) applications thanks to the great potential in cost reduction compared to the traditional solutions based on borehole heat ...
G-functions for bore fields with mixed parallel and series connections considering axial fluid temperature variations
(International Ground Source Heat Pump Association, 2018)
A semi-analytical method based on the finite line source (FLS) solution is presented to evaluate thermal response factors for geothermal bore fields with mixed series and parallel connections between boreholes. Each borehole ...