Heat transfer in the tank-inflorescence of Nidularium innocentii (Bromeliaceae): Experimental and finite element analysis based on X-ray microtomography

•The absence of water in the floral tank leads to a plant stress response.•Inflorescence with water in tank had a significantly larger flower size than the drought group.•In the drought group, several injuries were observed in flower and inflorescence bracts.•This inflorescence arrangement contributes to lower thermal variation.•The first application of μCT-based heat transfer FEA for plants as a method to complement the experimental setup results. In Bromeliaceae, various traits have evolved for the uptake and storage of water; however, their roles in bromeliad inflorescences remain unresolved. This study investigates the role of water in the flowers and inflorescences of Nidularium innocentii, and describes water as a protection mechanism. Individuals were divided into groups with and without water provision in inflorescences. Both groups were maintained with water in soil and leaves under the same environmental conditions. During anthesis, individuals were collected, and inflorescences were measured. Another specimen was prepared and scanned using X-ray microtomography (μCT), generating a high-resolution 3D model that was converted into a discretized geometry. Heat transfer finite element analysis (FEA) of the μCT-based geometry was then performed to simulate external temperature dissipation with the presence and absence of water in 3D. Flower size in the control group was significantly larger, and many injuries were observed in the drought group. FEA data indicated that the water environment led to lower temperature variation when compared to the air environment by significantly alleviating thermal amplitude. Water acted as a temperature stabilizer for the inflorescence, while its absence initiated physiological stress responses.