Experimental Flow Visualization of Human-Induced Flow Patterns for Indoor Ventilation Optimization

Effective indoor ventilation reduces disease transmission and improves air quality. However, models struggle to accurately define boundary conditions in real spaces because windows and vents usually act as both inlets and outlets. This research presents an innovative two-tank water-based experimental approach to study the problem and find ways of addressing this limitation. The study consists of a small acrylic 'office room' submerged within a large saline solution reservoir, incorporating a 37°C cylindrical heater representing a human occupant. A density- and viscosity-matched tracer fluid is injected from the apex to visualize thermal plumes generated by the heat source, revealing flow patterns analogous to indoor air movement. This water-based analog enables comprehensive observation and quantification of natural convection phenomena that are challenging for CFD models to capture. The resulting temperature and flow measurements will provide essential boundary condition data required for CFD model improvement. This research can transform ventilation design methodologies, leading to healthier indoor environments and more efficient HVAC systems.