Annular packed bed structures have the potential to overcome limitations of conventional fully packed bed types by offering radial distribution of airflow within them to enhance fluid-solid contact during adsorption and also to minimize pressure drops. In this paper, Z-annular flow configuration is experimentally investigated to evaluate its potential to enhance adsorption. Three typical diametrical ratios (Do/Di) corresponding to 2, 2.35 and 3.08, inferred from literature were used to investigate the adsorption performance of the Z-annular flow arrangement and compared with adsorption performance of a conventionally configured fully packed bed system of similar dimensions.The results showed the Z-annular flow configurations did perform better by achieving bed temperature reductions averaging between 4.22-5.47°C than conventional configuration types. Pressure drops were however observed to be relatively higher in the Z-annular flow configuration bed types than the conventional fully packed bed type due to the endplate in the Z-annular flow configuration impeding the airflow and subsequently causing flow reversal. Overall, the Zannular flow configuration was found to have the potential to enhance the adsorption capacity of packed beds however further investigation on optimum parameters for this enhancement may be required.

Helically Coiled Oscillating Heat Pipes (HCOHPs) have been designed and tested under laboratory conditions to investigate their potential to achieve isothermal adsorption when integrated with a cylindrical solid desiccant packed bed system. The HCOHPs fabricated out of copper, are essentially single turn closed loop oscillating heat pipes with their evaporator and condenser sections helically coiled. They were charged with ethanol, methanol and deionised water respectively at approximately 60% volume fill ratio and tested by slotting through their helically coiled evaporators an empty cylindrical copper vessel which allowed hot air to be blown through at various heat loads to ascertain their thermal performances.The results showed there were critical heat fluxes which varied with heat input amount at the evaporator, beyond which dry-out commenced and thermal resistance increased. These heat fluxes were ≤ 70 for the ethanol HCOHP and ≤ 105 for both the methanol and deionised water HCOHPs. Performance instabilities owing to liquid phase of the working fluid transitioning in the drying-out stage was observed for the methanol HCOHP beyond 234W. The variation of the effective thermal conductivities at the evaporators were found to influence the thermal contact resistance experienced at the contact interface of integration and the maximum heat input amount at the evaporators. Optimum performance between the HCOHPs was observed with the deionised water type. Overall, the HCOHPs were capable of managing relatively large amounts of heat input due to their helically coiled sections creating comparatively larger evaporator sections holding relatively more working fluid than the conventional serpentine single turn closed loop OHP system of the same volume and fill ratio. Investigations involving the visualization of the internal flow dynamics is recommended for future studies.

Double skin façades (DSFs), offer great views, architectural aesthetics, and energy savings. Yet, in a fire event the glass façade breaks leading to risks to human life and firefighting difficulties. Shading devices incorporated to prevent unfavourable heat gains to reduce cooling load though offer energy savings potentially present other challenges in firefighting and occupants’ evacuation. In this study, Fire Dynamic Simulator (FDS) was used to numerically investigate the spread of a 5 MW HRR polyurethane GM27 fire in a multi-storey double skin façade building with Venetian blinds placed in its cavity. The blinds were positioned 0.4 m away from the internal glazing, middle of the cavity and 0.4 m away from the external glazing respectively. In each blind position the slat angle was opened at 0°, 45°, 90° and 135° respectively. The results show peak inner glazing surface temperature ranged between 283°C to 840°C depending on the thermocouple position, the Venetian blind position and slat opening angle. Without Venetian blinds, peak inner glazing surface temperatures ranged between 468°C to 614°C. In all cases except when the slat angle was 0° and the blind was positioned closer to the outer glazing, the inner glazing surface temperature from the closest thermocouple (TC 14) above the fire room exceeded 600°C, the glass breakage temperature threshold. Overall, the Venetian blind position and slat opening angle influenced the spread of fire. Venetian blind combustibility and flammability were not considered and therefore recommended for future studies. Practical Application: Our manuscript helps to develop new thinking on mitigation of fire risks in buildings for architects, engineers and designers when incorporating Venetian blinds in Double Skin Façades (DSFs).

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