Experimental Investigation of Optimal Flow in Borehole Heat Exchanger at KTH Live-in Lab
This master's thesis proposes an experimental investigation to explore the question of optimal control of ground heat exchangers within a GSHP at the Live-in Lab on KTH campus.
Abstract
The urgency to address climate change has led to an increased interest in sustainable energy solutions. Ground source heat pump (GSHP) technology has emerged as a promising and efficient alternative for space heating and cooling. However, the operation of Boreholes Heat Exchangers (BHE), a critical component of GSHP systems, has largely been relying on traditional heuristic control strategies – i.e. strategies that work but are sub-optimal from an energy performance perspective. This master's thesis proposes an experimental investigation to explore the question of optimal control of ground heat exchangers within a GSHP at the Live-in Lab on KTH campus. The study aims to produce valuable data which will be confronted to models developed in parallel. The long term goal being to propose better operating strategies for the control of BHE in order to improve the performances of existing and new GSHP.
Who are you
You fuse curiosity with a commitment to climate action. You embrace hands-on tasks and thrive on turning theoretical insights into real-world solutions. Your foundation in thermodynamics, building physics, and/or energy engineering equips you to optimize energy systems sustainably.
Programming skills in Julia or Python, familiarity with controls and data acquisition are a plus.
1. Introduction
Climate change poses significant challenges, demanding innovative solutions to mitigate its impact. The need for sustainable heating and cooling technologies has led to the increasing adoption of GSHP systems. GSHPs utilize the stable temperature of the ground to extract and dissipate heat, offering a more environmentally friendly and energy-efficient alternative to traditional heating and cooling systems. Borehole heat exchangers play a crucial role in the functioning of GSHPs, transferring heat between the ground and the heat pump. Therefore, optimizing their performance is essential for maximizing the overall system efficiency.
Previous studies have found that GSHP system have relatively good performance but it could be better. In particular, parasitic loss related to circulation pumps have been identified as a potential source of improvement.
2. Goal
The primary objective of this master's thesis is to experimentally investigate the question of optimal control of ground heat exchangers at the Live-in Lab test facility. By conducting a series of tests and analyses, we aim to identify the flow rates that result in the most efficient heat transfer and energy utilization within the borehole heat exchanger. The findings will contribute to developing improved control strategies for GSHP systems and enable enhanced energy performance.
3. Preliminary Tasks
Literature Review
A comprehensive review of the existing literature on ground source heat pump systems, borehole heat exchangers, and optimal control strategies will be conducted. This step will provide a solid foundation for understanding the current state of research, identify research gaps, and guide the experimental design.
Define the Test Campaign
Based on the insights gained from the literature review, a detailed test campaign will be developed. This campaign will outline the different strategies to be testes together with the range of parameters to be used. Focus will be put on performing core tests to establish a robust and field-inspired baseline against wich the next tests will be evaluated.
Familiarize with Test Equipment
Prior to conducting the tests, the student will learn how to operate the equipment available at the Live-in Lab. This will involve understanding the operation of the ground source heat pump system and the control system (a PLC).
Performing the Tests
Following the preparation phase, the researcher will execute the planned test campaign at the Live-in Lab.
Analysis
Once the experimental data has been collected, a comprehensive analysis will be conducted. This analysis will involve examining the relationship between flow rates and heat transfer efficiency, as well as identifying any limitations or anomalies observed during the experiments. Statistical tools and data visualization techniques will be employed to interpret the results effectively.
4. Time Frame
The proposed timeline for this master's thesis project is as follows:
Contact person and supervisor:
