The monograph is the first book that reviews a variety of problems in different fluid mechanics disciplines that led to the concept of canopy, or penetrable roughness. Despite their diversity, many flows may be theoretically united by means of introducing distributed sinks and/or sources of momentum and heat and mass. Terrestrial vegetation, historically the first example of canopies, creates specific features of turbulence. Aquatic canopies exhibit a range of behaviour depending on the depth of submergence, geometrical forms of the obstacles and the patterns of their relative locations. These and other flows in engineering and environmental situations over surfaces with many obstacles are reviewed in terms of general concepts of fluid mechanics. They have been subject to examination by field-scale and laboratory experiments, and have been modelled and simulated using a variety of computational techniques. Distinct regions of the flows are identified. Application of the flow modelling is also relevant to predicting the dispersion of pollutants in these complex flows, particularly for releases in street canyons and fire propagation.Written by world-recognized experts, the book is of interest to researchers and students in general fluid mechanics and environmental physics, in hydraulics and meteorology, as well as in environment protection. TOC:Preface.- 1. Canopies, or EPRs.- 1.1. Vegetative canopies in meteorology.- 1.2. Vegetated river beds.- 1.3. Urban canopies.- 1.4. Spraying coolers.- 1.5. Other examples of EPR.- 1.6. Laboratory modelling of the canopy flows.- 1.7. Preliminary conclusion. Turbulence.- 2. Discrete and continuum models.- 2.1. Introduction.- 2.2. Over/through canopies.- 2.3. Computational models.- 2.4. Dispersion in canopies.- 2.5. Conclusion.- 2.6. Appendix A: Dispersion in street canyon.- 2.7. Appendix B: Notation and abbreviations.- 3. EPR of different structure.- 3.1. EPR of immobile elements.- 3.2. EPRs made up of mobile elements.- 3.3. Turbulence in EPRs.- 4. Flow in vegetation canopies.- 4.1. Introduction.- 4.2. Flow Above The Canopy.- 4.3. Flow Within The Canopy.- 4.4. Computational Representations of Canopy Flow.- 4.5. Higher-Order Closure Schemes.- 4.6. Large-Eddy Simulation.- 4.7. Contribution of Canopy Elements.- 4.8. Conditional Sampling and Composite Averaging.- 4.9. Empirical Orthogonal Function (EOF) Analysis.- 4.10.Summary.- 5. Topography and stable stratification.- 5.1. Introduction.- 5.2. The windfield over a canopy covered hill.- 5.3. The scalar field over a canopy covered hill.- 5.4. Stable Stratification.- 5.5. Summary and conclusions.- 6. Aquatic Canopies.- 6.1. Introduction: Comparison of Aquatic and Terrestrial Canopies.- 6.2. Emergent Canopies.- 6.3. Diffusion within Emergent Vegetation.- 6.4. Submerged Canopies.- 6.5. Summary.- 7. Vorticity annihilation, inviscid blocking.- 7.1. Introduction.- 7.2. Vorticity annihilation.- 7.3. Inviscid blocking.- 7.4. Modelling drag forces.- 7.5. Bubbly flows: high void fraction, high Re.- 7.6. Concluding remarks.- 8. Fires in Porous Media.- 8.1. Introduction.- 8.2. Forest and wildland fire statistics.- 8.3. Historic large urban fires.- 8.4. Fire classification.- 8.5. Modeling methodologies.- 8.6. Forest and urban climate meteorology.-8.7. Fluid mechanics of fires and porous canopies.- 8.8. Fire whirls and fire tornadoes.- 8.9. Numerical Modeling Fire Whirls.- 8.10.Conclusions and recommendations.- 9. Air emergencies and urban weather.- 9.1. Introduction.- 9.2. Applications to Urban Meteorology and Air Quality.- 9.3. Applications to Emergency Preparedness.- Conclusion.- Bibliography.- Index.-
