Energy Demand and Environmental Impact of Various Construction Scenarios of an Office Building in Morocco

International audienceThis paper assesses the thermal performance of an office building with an intermittent occupancy pattern, designed according to three construction scenarios. Annual simulations are carried out using TRNSYS software considering a Typical Meteorological Year (TMY) of six Moroccan cities referring to the representative zones of the recent Moroccan climatic zoning. The energetic and environmental performance of various passive energy efficiency measures are evaluated and discussed. The major finding of this work is that these energy measures can have a positive influence on reducing carbon footprint of the considered building. Annual loads can be reduced by about 20% in Agadir, 48% in Tangier, 53% in Fez 56% in Ifrane, 31% in Marrakech and 41% in Er-rachidia

A Numerical Analysis of Solid\textendashLiquid Phase Change Heat Transfer around a Horizontal Cylinder

International audienceA numerical study is conducted to analyze the melting process around a horizontal circular cylinder in the presence of the natural convection in the melt phase. Two boundary conditions are investigated one of constant wall temperature over the surface of the cylinder and the other of constant heat flux. A numerical code is developed using an unstructured finite-volume method and an enthalpy porosity technique to solve for natural convection coupled to solid-liquid phase change. The validity of the numerical code used is ascertained by comparing our results with previously published results. \textcopyright 2013 Elsevier Inc

Melting inside a Horizontal Cylindrical Capsule

International audienceThe role of natural convection on solid-liquid interface motion during constrained melting within a horizontal cylindrical capsule was investigated. A numerical code is developed using an unstructured finite-volume method and an enthalpy porosity technique to solve for natural convection coupled to solid-liquid phase change. Flow patterns for different Rayleigh numbers are presented. The resulting melt shapes and the temperature in the PCM provide conclusive evidence of the importance of natural convection on heat transfer in the melt region

Validation of diffuse correlation spectroscopy against 15O-water PET for regional cerebral blood flow measurement in neonatal piglets

Diffuse correlation spectroscopy (DCS) can non-invasively and continuously asses regional cerebral blood flow (rCBF) at the cot-side by measuring a blood flow index (BFI) in non-traditional units of cm2/s. We have validated DCS against positron emission tomography using 15O-labeled water (15O-water PET) in a piglet model allowing us to derive a conversion formula for BFI to rCBF in conventional units (ml/100g/min). Neonatal piglets were continuously monitored by the BabyLux device integrating DCS and time resolved near infrared spectroscopy (TRS) while acquiring 15O-water PET scans at baseline, after injection of acetazolamide and during induced hypoxic episodes. BFI by DCS was highly correlated with rCBF (R = 0.94, p < 0.001) by PET. A scaling factor of 0.89 (limits of agreement for individual measurement: 0.56, 1.39)×109× (ml/100g/min)/(cm2/s) was used to derive baseline rCBF from baseline BFI measurements of another group of piglets and of healthy newborn infants showing an agreement with expected values. These results pave the way towards non-invasive, cot-side absolute CBF measurements by DCS on neonates