SOLNET Milan 05.03.2008 Optimization of the air-to-water heat exchanger configuration for water preheating in open district heating nets Janybek Orozaliev

To my person 1998 – 2003 Kyrgyz-Russian Slavic University, Bishkek major: Renewable Energies 2003 – 2005 Kassel University (Germany) major: Power and Environmental Engineering master, scholarship from DAAD 10/2005 -? Kassel University (Germany) PhD study scholarship from Volkswagen Foundation 09/06 – 02/10

Strong intercontinental climate Kyrgyzstan – favorable conditions for solar heating Strong intercontinental climate In summer: high solar irradiation and ambient temperatures Open district heating net Hot water withdraw directly out of the net High steady load and low inlet temperatures Solar preheating

Strong intercontinental climate Kyrgyzstan – favorable conditions for solar heating Strong intercontinental climate In summer: high solar irradiation and ambient temperatures Open district heating net Hot water withdraw directly out of the net High steady load and low inlet temperatures  Application of uncovered collectors

Strong intercontinental climate Strong intercontinental climate Kyrgyzstan – favorable conditions for solar heating Strong intercontinental climate In summer: high solar irradiation and ambient temperatures Strong intercontinental climate In summer: high solar irradiation and ambient temperatures Open district heating net Hot water withdraw directly out of the net High steady load and low inlet temperatures Open district heating net Hot water withdraw directly out of the net High steady load and low inlet temperatures Tamb > Tin  Application of uncovered collectors

Uncovered air collector Air-to-water heat exchanger (AHX) Multicomponent-System Uncovered air collector Air-to-water heat exchanger (AHX) Uncovered collector Air Collector (31 m²) Uncovered Collector (62 m²) Air-to-Water Heat Exchanger (AHX)

How should components be dimensioned? (depending on climate) Multicomponent-System – Research What is the optimal configuration of the system? (depending on climate and boundary conditions) How should components be dimensioned? (depending on climate) How should components be operated/controlled? (depending on weather) Potential analysis in CIS countries  mathematical models  experimental set up

Uncovered air collector Air-to-water heat exchanger (AHX) My part Uncovered air collector Air-to-water heat exchanger (AHX) Uncovered collector

Optimization: Optimal configuration of AHX for this application Aims and work packages Extension of numerical models: Description of thermal and hydraulical performance of AHX Further developing of the model, which considers geometry in detail Based on Nu-correlations (not CFD) Cost functions: of components depending on their properties (geometry, power, etc) Optimization: Optimal configuration of AHX for this application Optimization calculations coupled with system simulations in TRNSYS Guidelines for dimensioning and operation of AHX: e.g. in form of characteristic curves for different climates

Thanks for your attention Janybek Orozaliev Solar and Systems Engineering Kassel University, Germany +49 561 804-2636 orozaliev@uni-kassel.de

Arbeitsbereich Christian Budig unabgedeckter Luftkollektor Luft-Wasser-Wärmeübertrager unabgedeckter Kollektor

Richtlinien zur Dimensionierung und Regelung von Systemen: Ziele und Arbeitspakete Christian Budig Identifizierung geeigneter Luftkollektorsysteme: Untersuchung von Folien- und Polymerkollektoren; thermische Abbildung soll über bereits vorhandene Kennlinien erfolgen Validierung und Parameteranpassung: Die numerischen Modelle sollen anhand der Messdaten validiert und eine Parameteranpassung vorgenommen werden Systemsimulationen: Untersuchung der mögl. Systemkonfigurationen in Abhängigkeit verschiedener Klimata Richtlinien zur Dimensionierung und Regelung von Systemen: