Research Projects

Variable Refrigerant Flow (VRF) systems are essential for maintaining comfortable indoor environments in homes and commercial spaces. These systems use refrigerant as a cooling medium, offering precise temperature control and energy efficiency. The evaporator, a key component, is responsible for heat absorption, transfer, energy efficiency, zoning capabilities, and dehumidification. However, traditional evaporators have drawbacks such as limited installation space, design constraints, increased refrigerant charges, complex piping, maintenance challenges, and environmental concerns. Technological advancements aim to overcome these challenges and enhance VRF system efficiency and performance. One innovation is the flooded evaporator, which depends on the boiling heat transfer coefficient (HTC) and refrigeration capacity. Passive techniques, such as microstructure formation, extended fins, and coated tubes, have gained popularity for improving HTC and capacity while remaining cost-effective. High flux tube bundles are also used to increase surface HTC and reduce system size. Selecting refrigerants with low Global Warming Potential (GWP) and low Ozone Depletion Potential (ODP) is crucial for addressing climate change, complying with regulations, protecting the ozone layer, and demonstrating environmental responsibility. This study aims to explore passive techniques, flow control mechanisms, and appropriate refrigerant selection to optimize the performance of flooded evaporators, ultimately improving energy efficiency, reducing operating costs, and minimizing environmental impact.