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Abstract A building integrated cooling facade is proposed in this paper. It is a fan-assisted system that consists of two vertical plenums. The first plenum was made of black aluminium transpired plate and a sandtile wall, while the second plenum is formed by the sandtile wall and the building wall. The aluminium plate served as a solar collector and the sandtile wall was an evaporative pad. The reverse side of the sandtile wall that contacted with the air in the second plenum was coated with a water-resistant layer, hence the air was cooled without adding any moisture into it. The facade cooling performance under various operating conditions is investigated through experiment and theoretical analyses. It is found that inlet water temperature is the key factor affecting the cooling performance. In terms of cooling efficiency, the energy consumption to generate 1 kW of cooling that cooling the air to 293 K is only 0.52 W, which is similar to the amount of energy required by some of the solar indirect evaporative cooling and desiccant cooling systems.

In a double-blind, cross-over study of twenty male volunteers intravenous injection of 0.4 mg naloxone prevented the impairment of psychomotor performance induced by low levels of blood alcohol. The possibility that alcohol produces intoxication by stimulating the release of endogenous opioid peptides should be investigated.

Abstract The pressure-loss coefficient for a duct junction of square cross-section was determined using computational fluid dynamics (CFD). The predicted junction pressure-loss coefficient for combining flows was generally in good agreement with experimental data from the literature. The junction pressure-loss coefficient was associated with the flow from the side branch to the duct carrying the total flow.

Abstract Local thermal discomfort in offices with displacement ventilation is investigated using computational fluid dynamics. The standard κ-ϵ turbulence model is used for the prediction of indoor air flow patterns, temperature and moisture distributions, taking account of heat transfer by conduction, convection and radiation. The thermal comfort level and draught risk are predicted by incorporating Fanger's comfort equations in the airflow model. It has been found that for sedentary occupants with summer clothing common complaints of discomfort in offices ventilated with displacement systems result more often from an unsatisfactory thermal sensation level than from draught alone. It is shown that thermal discomfort in the displacement-ventilated offices can be avoided by optimizing the supply air velocity and temperature. It is also shown that optimal supply air conditions of a displacement system depend on the distance between the occupant and air diffuser.

Abstract In this study, pyrolysis of sawdust and pinewood (120–250 μm) was conducted in a drop-tube furnace (DTF) at temperatures of 900, 1100, 1300 °C and residence times of 50–600 ms in both CO2 and N2 atmospheres. The samples are fed at a rate of 5–10 g/h in a gentle flow of nitrogen (1 L/min) to ensure laminar flow. A silica tracer method has been developed to accurately determine the high temperature volatile matter yields. The elemental analysis of chars collected allowed the study of the release of nitrogen. BET surface area, scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses were also carried out to study the chars produced. Burnout tests were conducted at 1100 °C, an O2 concentration of 5% v/v in N2 and CO2 respectively, using the chars produced at the same temperature and a residence time of 200 ms. In nitrogen, the maximum volatile yield achieved was 97 wt% while in CO2, the maximum volatile yield was over 99 wt% for residence times above 200 ms, indicating virtually complete gasification of the char. These are the highest reported volatile matter yields for biomass obtained using a DTF. The release of nitrogen into the volatile phase is proportional to the yield of volatiles both for air and oxy-fuel conditions. SEM images revealed higher porosities of the DTF CO2 chars than those of N2, being consistent with their higher BET surface areas. Faster char burnout was obtained for oxy-fuel firing attributable to the CO2/char gasification reactions. The results will be useful for modeling dedicated oxy-biomass firing and co-firing systems.

Abstract Thermochemical energy storage materials have advantage of much higher energy densities compared to latent or sensible heat storage materials. Metal hydrides show good reversibility and cycling stability combined with high enthalpies. They can be used for short and long-term heat storage applications and can increase the overall flexibility and efficiency of solar thermal energy production. Metal hydrides with working temperatures less than 500 °C were in the focus of research and development over the last years. For the new generation of solar thermal energy plants new hydrides materials with working temperatures above 600 °C must be developed and characterized. In addition to thorough research on new metal hydrides, the construction and engineering of heat storage systems at these high temperatures are challenging. Corrosion problems, hydrogen embrittlement and selection of heat transfer fluids are significant topics for future research activities.

There is considerable interest in the use of venturis to meter gas/solids flows. However, as there are two unknowns, the gas and solids flow rates, two pieces of information are required to calculate these values. It has been suggested that the pressure drop to the throat of the venturi and the recovery of pressure across the diffuser can be used for this purpose. A quasi-one-dimensional model for gas/solids flows in venturis has been developed. This model allows for the acceleration and deceleration of the gas and the solid particles as well as for changes in the thickness of the boundary layer. The last term is particularly important in the prediction of the pressure recovery in the diffuser. Predictions of the model have been validated against (previously published) experimental data. These show excellent agreement between the model and the experiments. In places the predictions are better than those from Computational Fluid Dynamics.