A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Wind- and stack-assisted mechanical ventilation with heat recovery and night cooling
The dual-sided issue of indoor environment and energy consumption have become increasingly important in building design. One possible solution is to ventilate by passive means, such as by stack eect and wind pressure, but this requires the development of new concepts and components. Here we have presented the outline of a heat recovery concept suitable for stack and wind-assisted mechanical ventilation systems with total system pressure losses of 74Pa. The heat recovery concept is based on two air-to-water exchangers connected by a liquid loop powered by a pump. The core element of the concept, a prototype of a heat exchanger, was developed based on design criteria about pressure drop, eciency and production concerns. The exchanger is based on banks of plastic tubing cris-crossing the air flow, thus creating approximate counter flow between air and water. Round PE plastic tubing is used. The tubing is commonly used for water-based floor-heating systems. Oval or even wing shaped tubes may have better heat transfer and lower drag coecient, but round tubes require less meticulous production procedures. The tubing used here is mass-produced, cheap, and flexible but the current design does require many fittings. Multiple design proposals were modeled and investigated to determine the optimal solution with respect to pressure drop, heat transfer, and production feasibility. Software models were developed to simulate the temperature distribution within the tube bank. The final design involves two parallel tubes cris-crossing the air fixated in a `radiator' by tube bending brackets and spacers. The radiators are stacked in a staggered grid to force a more tortuous air flow and generate as much heat transfer as possible. The performance was confirmed by comparing the pressure drop and heat transfer measured on a section with numerical fluid calculations and literature sources. The measurements and calculations agree reasonably well. A full scale implementation was achieved in a part of building 118 at Dept. of Civil ...
Wind- and stack-assisted mechanical ventilation with heat recovery and night cooling
The dual-sided issue of indoor environment and energy consumption have become increasingly important in building design. One possible solution is to ventilate by passive means, such as by stack eect and wind pressure, but this requires the development of new concepts and components. Here we have presented the outline of a heat recovery concept suitable for stack and wind-assisted mechanical ventilation systems with total system pressure losses of 74Pa. The heat recovery concept is based on two air-to-water exchangers connected by a liquid loop powered by a pump. The core element of the concept, a prototype of a heat exchanger, was developed based on design criteria about pressure drop, eciency and production concerns. The exchanger is based on banks of plastic tubing cris-crossing the air flow, thus creating approximate counter flow between air and water. Round PE plastic tubing is used. The tubing is commonly used for water-based floor-heating systems. Oval or even wing shaped tubes may have better heat transfer and lower drag coecient, but round tubes require less meticulous production procedures. The tubing used here is mass-produced, cheap, and flexible but the current design does require many fittings. Multiple design proposals were modeled and investigated to determine the optimal solution with respect to pressure drop, heat transfer, and production feasibility. Software models were developed to simulate the temperature distribution within the tube bank. The final design involves two parallel tubes cris-crossing the air fixated in a `radiator' by tube bending brackets and spacers. The radiators are stacked in a staggered grid to force a more tortuous air flow and generate as much heat transfer as possible. The performance was confirmed by comparing the pressure drop and heat transfer measured on a section with numerical fluid calculations and literature sources. The measurements and calculations agree reasonably well. A full scale implementation was achieved in a part of building 118 at Dept. of Civil ...
Wind- and stack-assisted mechanical ventilation with heat recovery and night cooling
Hviid, Christian Anker (author) / Svendsen, Svend (author)
2012-01-01
Hviid , C A & Svendsen , S 2012 , Wind- and stack-assisted mechanical ventilation with heat recovery and night cooling . Technical University of Denmark, Department of Civil Engineering .
Book
Electronic Resource
English
DDC:
690
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