Metal-organic framework-based desiccant-coated heat and mass exchanger to engineer effective bus air conditioning systems utilising latent and sensible heat recovery

Abstract

The present study evaluates the performance of desiccant-coated heat exchangers (DCHE) that utilise both latent and sensible heat recovery for an energy-efficient bus air-conditioning system. A prototype unit incorporating a metal–organic framework (MOF)-coated DCHE was experimentally and numerically analysed under different environmental conditions. Key performance metrics included humidity ratio difference (Δx) of air supplied to the indoor environment. The prototype unit demonstrated a dehumidification ability of around 2.7 g/kg(DA) with a coolant temperature of 20 °C and a heating fluid temperature of 50 °C. The integration of heat recovery ventilation (HRV) reduced the cooling load by around 15 % compared to without HRV configurations. Geometric modifications, such as increasing the DCHE width to about 2.2 times larger that of the prototype, enabled the DCHE unit to achieve the target Δx of 4.88 g/kg(DA). These results highlight the potential of MOF-based DCHE units to reduce energy consumption in bus HVAC systems, thus contributing to more sustainable transportation solutions.