Carrier gas based thermodynamic cycles are common in water desalination applications.These cycles often require condensation of water vapor out of the carrier gas stream. Since the carrier gas is most likely a non-condensable gas present in very high concentrations (60-95%), a large additional resistance to heat transfer is present. We propose to reduce the aforementioned thermal resistance by condensing the vapor-gas mixture in a column of cold liquid rather than on a cold surface by using a bubble column heat exchanger. A theoretical predictive model for estimating the heat transfer rates and new experimental data to validate this model are described. The model is purely physics based without the need for any adjustable parameters, and it is shown to predict heat rates within 0% to -20% of the experimental values. The experiments demonstrate that heat transfer rates in the proposed device are up to an order magnitude higher than those achieved in existing state-of-the-art dehumidifiers.Keywords: condensation, bubble column, non-condensable gas, thermal resistance model, dehumidification, moist air, carrier gas * Corresponding author c p specific heat capacity at constant pressure (J/kg·K) c p,g average specific heat capacity at constant pressure of the vapor-air mixture (J/kg·K) T air local energy-averaged temperature of the air-vapor bubble (T coil local temperature of the coil surface (T column local energy-averaged temperature of the liquid in the column (T coolant local energy-averaged temperature of the coolant in the coil (

Temperature variations inside a car underhood are largely controlled by the heat originating from the engine block and the exhaust manifold. Excessive temperatures in the underhood can lead to the faster deterioration of engine components and may affect the thermal comfort level inside the passenger cabin. This paper presents computational fluid dynamics investigations to assess the performance of a heat shield in lowering the peak temperature of the engine components and firewall in the underhood region of a typical passenger car. The simulation used the finite volume method with the standard k-ε turbulence model and an isothermal model for the heat transfer calculations. The results show that the heat shield managed to reduce the peak temperature of the engine components and firewall by insulating the intense heat from the engine block and exhaust and regulating the airflow inside the underhood region.