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Title: Test-and-Rate Methods for Thermosiphon Solar Water Heaters

Abstract

Simulation models for innovative thermosiphon solar systems (TS) have been generally unavailable, hindering innovative system design/optimization and system rating. A TRNSYS module is introduced that calculates the mass flow rate in general natural convection loops, allows use of any existing tank and heat-exchanger modules, and handles reverse flow in TS when used with a new pipe module. To achieve desired rating accuracy, it is proposed that the flow rate sub-model in the underlying rating simulation be calibrated via nonintrusive flow data from an assembled system. Three innovative TS are being tested to validate the new modeling and the proposed test-and-rate method: two unglazed systems and a glazed polymeric system. An ultrasonic meter and a calorimetric flow-rate method both showed that model friction was high by {approx}3X. After calibration, the model showed good agreement on both long-term collected energy and tank temperatures.

Authors:
; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
981989
DOE Contract Number:
AC36-08GO28308
Resource Type:
Conference
Resource Relation:
Conference: Proceedings of the Solar 2007 Conference, 8-12 July 2007, Cleveland, Ohio (CD-ROM); Including Proceedings of 36th ASES Annual Conference, Proceedings of 32nd National Passive Solar Conference, and Proceedings of the 2nd Renewable Energy Policy and Marketing Conference
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; ACCURACY; AGREEMENTS; CALIBRATION; DATA; ENERGY; ENERGY POLICY; FLOW RATE; FRICTION; MARKETING; MASS; MEETINGS; METERS; NATURAL CONVECTION; PIPES; PROCEEDINGS; SIMULATION; SOLAR SYSTEM; SOLAR WATER HEATERS; TANKS; ULTRASONIC WAVES; Buildings; Solar Energy - Thermal

Citation Formats

Burch, J., Shoukas, G., Brandemuhl, M., and Krarti, M. Test-and-Rate Methods for Thermosiphon Solar Water Heaters. United States: N. p., 2007. Web.
Burch, J., Shoukas, G., Brandemuhl, M., & Krarti, M. Test-and-Rate Methods for Thermosiphon Solar Water Heaters. United States.
Burch, J., Shoukas, G., Brandemuhl, M., and Krarti, M. Mon . "Test-and-Rate Methods for Thermosiphon Solar Water Heaters". United States. doi:.
@article{osti_981989,
title = {Test-and-Rate Methods for Thermosiphon Solar Water Heaters},
author = {Burch, J. and Shoukas, G. and Brandemuhl, M. and Krarti, M.},
abstractNote = {Simulation models for innovative thermosiphon solar systems (TS) have been generally unavailable, hindering innovative system design/optimization and system rating. A TRNSYS module is introduced that calculates the mass flow rate in general natural convection loops, allows use of any existing tank and heat-exchanger modules, and handles reverse flow in TS when used with a new pipe module. To achieve desired rating accuracy, it is proposed that the flow rate sub-model in the underlying rating simulation be calibrated via nonintrusive flow data from an assembled system. Three innovative TS are being tested to validate the new modeling and the proposed test-and-rate method: two unglazed systems and a glazed polymeric system. An ultrasonic meter and a calorimetric flow-rate method both showed that model friction was high by {approx}3X. After calibration, the model showed good agreement on both long-term collected energy and tank temperatures.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

Conference:
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  • Conference paper regarding research in modeling and test-and-rate methods for thermosiphon solar domestic water heaters.
  • No abstract prepared.
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