Indonesia's rapid urbanization and population growth have driven a sharp increase in demand for air conditioning systems, contributing to rising electricity consumption, fossil fuel dependence, and carbon emissions, while simultaneously limiting thermal comfort access for low-income households in tropical urban settings. Existing passive cooling alternatives either rely on water supply and electricity, lack aesthetic adaptability for modern interiors, or remain unrealized beyond theoretical models — leaving a gap for a modular, electricity-free passive ventilation solution suitable for dense tropical housing. This study introduces AirMorph, a passive ventilation module designed on the Venturi and Bernoulli principles to accelerate indoor airflow without mechanical or electrical input. The research employed a three-stage methodology: 3D modelling using SketchUp, Computational Fluid Dynamics (CFD) numerical simulation using ANSYS Fluent, and controlled field testing with digital thermometer measurement. CFD results confirmed accelerated airflow and reduced pressure in the module's narrow cross-section, consistent with the Venturi effect. Field testing showed a consistent average indoor temperature reduction of 1.6 °C per hour, from 31.9 °C to 30.3 °C. Although this reduction is smaller than comparable passive products, AirMorph's key advantages lie in its modular plug-and-play design, compact dimensions, electricity-free operation, and compatibility with modern interior aesthetics — making it a practical and scalable passive cooling solution for densely populated tropical environments.