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The purpose of the paper is to predict the aerodynamic performance of a complete scale model H-Darrieus vertical axis wind turbine (VAWT) with end plates at different operating conditions. This paper aims at understanding the flow physics around a model VAWT for three different tip speed ratios corresponding to three different flow regimes.

This study achieves a first three-dimensional hybrid lattice Boltzmann method/very large eddy simulation (LBM-VLES) model for a complete scaled model VAWT with end plates and mast using the solver PowerFLOW. The power curve predicted from the numerical simulations is compared with the experimental data collected at Erlangen University. This study highlights the complexity of the turbulent flow features that are seen at three different operational regimes of the turbine using instantaneous flow structures, mean velocity, pressure iso-contours, blade loading and skin friction plots.

The power curve predicted using the LBM-VLES approach and setup provides a good overall match with the experimental power curve, with the peak and drop after the operational point being captured. Variable turbulent flow structures are seen over the azimuthal revolution that depends on the tip speed ratio (TSR). Significant dynamic stall structures are seen in the upwind phase and at the end of the downwind phase of rotation in the deep stall regime. Strong blade wake interactions and turbulent flow structures are seen inside the rotor at higher TSRs.

The computational cost and time for such high-fidelity simulations using the LBM-VLES remains expensive. Each simulation requires around a week using supercomputing facilities. Further studies need to be performed to improve analytical VAWT models using inputs/calibration from high fidelity simulation databases. As a future work, the impact of turbulent and nonuniform inflow conditions that are more representative of a typical urban environment also needs to be investigated.

The LBM methodology is shown to be a reliable approach for VAWT power prediction. Dynamic stall and blade wake interactions reduce the aerodynamic performance of a VAWT. An ideal operation close to the peak of the power curve should be favored based on the local wind resource, as this point exhibits a smoother variation of forces improving operational performance. The 3D flow features also exhibit a significant wake asymmetry that could impact the optimal layout of VAWT clusters to increase their power density. The present work also highlights the importance of 3D simulations of the complete model including the support structures such as end plates and mast.

Accurate predictions of power performance for Darrieus VAWTs could help in better siting of wind turbines thus improving return of investment and reducing levelized cost of energy. It could promote the development of onsite electricity generation, especially for industrial sites/urban areas and renew interest for VAWT wind farms.

A first high-fidelity simulation of a complete VAWT with end plates and supporting structures has been performed using the LBM approach and compared with experimental data. The 3D flow physics has been analyzed at different operating regimes of the turbine. These physical insights and prediction capabilities of this approach could be useful for commercial VAWT manufacturers.

Landfill capping is a mandatory post closure procedure in Australia to isolate the deposited wastes from the outside environment, mainly water. Compacted clay caps are predominantly used in Australian landfills. Recent studies have shown that clay caps have shorter life span and fail to prevent percolation of water due to cracking. This paper aims to discuss a new technology called “Phytocapping” that has been trialled at Lakes Creek landfill in Rockhampton.

In this technique, trees were used as “bio‐pumps” and “rainfall interceptors” and soil cover as “storage” of water. The field performance of the phytocapping system was measured based on its ability to minimise water percolation into waste. Tree growth, transpiration, canopy rainfall interception and methane emission were monitored over three years. The percolation rate was modelled using HYDRUS 1D code for two different scenarios (with and without vegetation) for the thick (1,400 mm soil) and thin (700 mm soil) phytocaps respectively.

Results from the modelling showed percolation rates of 16.7 mm yr⁻¹ in thick phytocap and 23.8 mm yr⁻¹ in thin phytocap, both of which are markedly lower than those expected from a clay cap. Results from monitoring and observations showed that 19 of 21 tree species grew well in the harsh landfill environment. However, the correct species selection is very important for the long‐term sustainability of the phytocap. Results also show that phytocaps can reduce a significant amount of methane emission from landfills.

The cost of landfill capping is escalating and is putting a lot of financial and legal pressure on the small and medium sized local governments in Australia. The phytocapping technique not only offers financial benefits but also has some environmental and commercial benefits.

The paper focuses on a new technology being used in waste management.