Determination of air exchange rates in naturally ventilated barns - Validation of prediction models 2.0

• Applicant: Dr. Sabrina Hempel
• Subject Area: Plant Cultivation, Plant Nutrition, Agricultural Technology ; Fluid Mechanics ; Animal Breeding, Animal Nutrition, Animal Husbandry
• Term: since 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 397548689

With the mathematic modelling in BeLuVa we gained first insights on how boundary conditions affect the air exchange rate (AER) in individual animal occupied zones (AOZ) and local ratios of target-to-tracer gas concentration. This is a prerequisite for the design of “healthy” husbandry systems with minimal pollutant and pathogen loads as well as for the evaluation of uncertainties of emission estimates based on gas balancing methods. Building up on BeLuVa, the first objective of BeLuVa 2.0 is a detailed investigation on how the AOZ configuration and so far neglected heat transfer processes affect the accuracy of the predicted gas dispersion pattern and the AER of AOZs, towards a further refinement of the BeLuVa model. The second objective is to broaden the basic understanding of the influence of wind incident to permit to identify tipping points where wind direction changes induce particularly strong modifications in the flow pattern. Objective three is the refinement of the parametric models for local AER and gas balancing accuracy derived in BeLuVa. The model results will be cross-validated with wind tunnel and on-farm measurements. The expected fundamental insights are a basis for the further development of models and methodologies to determine AERs and emission processes. The transferability to different barn types and climate conditions permits to quantify the accuracy of currently used measuring approaches in dependence of the actual boundary conditions.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Thomas Amon