CONTEXT AND OBJECTIVE:
CONTEXT AND OBJECTIVE The most promising technology for better stratification => a mantle storage tank with injection of the collector fluid at several levels in the mantel=> development a zonal model from this type. Low-flow system (7 to 15 litres/hour per solar collector m2 ) => the most promising way for improving the solar water heater performance. Increasing the performance by taking advantage of the low flow => better stratification in the tank. Associating the developed model with other model components in TRNSYS => optimization the control and behavior of low-flow SDHW.
Slide3:
ZONAL MODELING Hypotheses for solving the problem=> imposing a scenarios of the fluid flow studied. Exchange diagram relative to different zones with hot boundary layer Exchange diagram relative to different zones with cold boundary layer Resolution of the differential equations => numerical scheme of finite differences (implicit method). Solution for this type of model => knowing mass flow rate for each layer => calculate volume flow rate Q(X) by integral method of turbulent thermal boundary layer equations.
Slide4:
TESTING AND VALIDATION Two kinds of tests were carried out on Validation
Analyzing the thermal behavior of a low-flow solar water heater => optimizing the system control and behavior.
Slide5:
CONCLUSION The results of the test campaign => validation of the developed mantle storage tank model. This model with a good thermal stratification => new type in TRNSYS (Type 130) => using for studying thermal systems by associating with other components. With this new model we find the means to optimize the low-flow solar water heater