Thermal and fluid flow analysis of bifluid PVT collector using Pyomo-based modeling and experimentation

The design of bifluid Photovoltaic-Thermal (PVT) collectors is hampered by a modeling gap between computationally prohibitive simulations and less transparent data-driven models. This paper bridges this gap by developing physics-informed performance insights derived from a novel thermo-fluid framework. We present a Differential-Algebraic Equation (DAE) model built in the Pyomo suite and validated against experimental data; the model efficiently solves the governing PDEs using orthogonal collocation. This enables a comprehensive parametric study that quantifies critical design trade-offs, such as the thermal competition between the air and water streams. The analysis yields deep physical insights into the system's governing dynamics, specifically revealing that increasing cooling tube density serves as a synergistic strategy that concurrently improves thermal efficiency and significantly reduces parasitic pumping power. These insights directly inform practical engineering application and design optimization.