Showing posts from June, 2018

Project report

I've now finished and turned in my report for the initial research project about the StackHR concept. The full report is available HERE . Enjoy the read! Edit 23-06-2018: I just realized that Aarhus Universities copyright agreement does not cover widespread publishing of student papers that feature figures from 3rd party sources. I have therefore removed all figures that were reprinted in the literature review section of the paper. Feel free to send me an email if you would like a copy of the original report with all the figures. Edit 19-09-2018: I've finally gotten around to update the report to only exclude figures by the people I wasn't able to get a hold of, just press the link above. Again, if you would like a copy of the original report with all the figures just send me an E-mail on

Test Setup

The research project during which I have been working on the StackHR concept is coming to an end soon as I'll have to finish up and turn in a report with all my findings by the end of this month. Luckily that won't be the end of development on StackHR though! For my master thesis project starting next semester, I will construct and perform tests on a prototype of a StackHR tube with guidance from my supervisor Professor Zhang. I very much look forward to this project and I have already started the first preparations. Below is a sketch I've made of the test setup I'm planning on using, but things might change somewhat down the road.

Yearly Energy Saving

I've run calculations to investigate annual energy savings using the StackHR concept in place of traditional natural ventilation for Danish climate. The model assumed a Ø160 mm PVC pipe wrapped in 30 mm of glass fiber insulation as the outer tube, and a thin walled aluminium pipe as the inner tube. At no point did the heat recovery efficiency drop below 52%. On average it was found to be approximately 60% with an average flow rate of just over 2.5 L/s. With a standard deviation of 1.2, the flow rate is relatively stable attesting to the benefits of selecting stack effect as the driving force for the ventilation. Up to 4 of these tubes per slab segment (1200 mm wide) can be integrated, achieving an occupant density of 1 occupant per 8 m^2 floor area. For each of the StackHR tubes used, 228 kWh of heat per year is recovered and thereby saved in energy costs. I have added a new page describing the calculations and methodology as well as additional information about why one should choo