In recent years, cities have experienced frequent climate changes and deteriorating wind environments. Urban vegetation has become an important measure to improve local microclimates with its flexible configuration. Leaves and branches also reorient with the direction of wind, affecting the airflow through the tree. However, trees are usually considered as stationary porous media areas and are not influenced by wind speed in existing numerical simulation studies. Therefore, by considering the response of a tree under natural wind, this study established a fitted relationship between porosity and wind speed by measuring the porosity of trees at different wind speeds in the field. A numerical model of the wind response of the tree was developed, and the tree drag coefficient was changed using the additional source term method to verify the feasibility of the model by measuring the wind environment behind the tree. To understand the effect of the wind-induced response on the surrounding flow field and its variation pattern, the surrounding flow fields of stationary tree (T-S) and wind-induced tree (T-D) at different wind speeds were compared and analyzed. The effect of porosity and height-to-width ratio under the wind-induced response of trees on the wind environment were quantified. It was found that at different wind speeds, as the wind speed increases, the tree porosity gradually increases and the drag coefficient decreases accordingly. The effective shading distance after wind response was 2.4H, which was 0.3H less compared to vertically fixed trees. The minimum wind speed increased linearly with plant porosity, and the minimum wind speed occurrence location and wind speed recovery distance were linearly and negatively correlated with tree height-to-width ratio. Therefore, the flow field around the tree was simulated to provide references for guiding tree planting and mitigating urban wind environments.

Optimizing solar radiation and daylighting performance is a fundamental concern in architectural design, as these factors are directly linked to enhancing building energy efficiency and environmental comfort. This study seeks to balance solar radiation and daylighting performance through architectural geometry optimization, includes building’s length, width, height, orientation, and mass distribution. Parametric modeling based on the additive and subtractive design generation algorithms included in EvoMass on the Grasshopper platform, with the goal of minimizing the solar radiation variation between summer and winter on building envelopes and maximizing useful daylight illuminance (UDI). A multi-objective evolutionary algorithm named Steady-State Island Evolutionary Algorithm (SSIEA) was applied to optimize the building geometry, ultimately yielding the Pareto front optimal solution. When compared to the reference building, the optimized design enables the building to achieve a more balanced solar radiation distribution across different seasons, resulting in a 26.89% improvement in performance. Additionally, the building’s daylighting performance is enhanced by 19.85%. The results demonstrate that leveraging the Pareto front in the early stages of building geometric form design provides architects with effective strategies and solutions for geometry optimization, enabling performance-based design decisions in subsequent stages.

This paper presents comprehensive research of the advantages and applicability of various concrete carbonation detection methods. Employing a combination of Phenolphthalein indicator (PI), Thermogravimetric analysis (TGA), X-ray phase analysis (XRD), Fourier transform infrared spectroscopy (FTIR), and Quantitative calcium carbonate analysis (CA), a detailed comparison to determine the carbonation depth in the partial carbonation zone of concrete specimens is conducted. Among the quantitative analysis methods, CA measures CaCO₃ content based on chemical reactions, while TGA obtains the concentration distribution of Ca(OH)₂ and CaCO₃. Among qualitative analysis methods, XRD tested the intensity distribution of Ca(OH)₂ and CaCO₃, while FTIR traced the characteristic peaks of C-O functional groups in a specific spectral range to determine the depth of carbonation of concrete. Results indicate that the depth of carbonation values measured by CA, TGA, XRDA, and FTIR are 2–3 times higher than those measured by PI. This research may provide valuable insights for the design of carbonation detection in concrete.

In view of the urgent concerns pertaining to the proliferation of rural wastewater discharges and the imperative for decentralized treatment, this article examines the phenomenon of physical clogging in a small-scale horizontal submerged flow artificial wetland system. Through a combination of experimental analysis and CFD-EDM numerical simulations, the impact of clogging on the hydraulic efficiency of the system was subjected to rigorous examination. Based on these findings, an innovative design strategy was proposed, namely the addition of vertical baffles. The experimental results demonstrate that this strategy can markedly prolong the duration of complete clogging of the system by up to 15% and enhance the hydraulic efficiency by 21%. Based on this, a small-scale horizontal submerged artificial wetland wastewater treatment system was designed for rural areas and successfully implemented in Fanrong Village, Rui’an City. This resulted in an enhanced wastewater treatment effect and an improved rural landscape. The findings of this study contribute to the development of a more rational and effective sewage treatment solution for rural areas.

Integrated vertical flow constructed wetland (IVCW) is a new type of ecological wastewater treatment, and its internal hydrodynamic characteristics are crucial for the efficiency of pollutant removal. To enhance the hydrodynamic characteristics and pollutant removal efficiency of IVCWs, this study systematically investigated the influence mechanisms of substrate arrangement, layer thickness ratio, and hydraulic load on the internal flow field and hydrodynamic characteristics of the IVCW system using CFD technology. Based on these findings, an optimized IVCW system was proposed, and its pollutant removal performance was examined through field measurements. The results showed that the highest hydraulic efficiency within the system (λ = 0.835) was achieved when the substrate was arranged in descending order of resistance coefficient from top to bottom (medium, high, low), with a layer thickness ratio of 1:4:1 and a hydraulic load of 0.7 m/d. Compared to the control group, the optimized IVCW exhibited significantly higher average removal rates for COD (Chemical Oxygen Demand), TP (Total Phosphorus), and TN (Total Nitrogen).This study provides technical support for the improvement and application of the IVCW system and holds significant implications for ecological wastewater treatment.

In order to improve the level of the urban living environment and improve the comfort level of the microclimate, this paper investigates and simulates numerically the influence on the wind environment of different tree species in various tree array layouts, aiming to enhance wind comfort in tree landscapes and reduce the risk of high wind speeds. Initially, the study analyzes the commonly used tree species in Hangzhou’s urban tree arrays (beech, soapberry, and camphor trees), summarizing three types of tree array layouts: retention, through, and enclosure. Subsequently, standard tree models are established to define their crown porosity, trunk elastic modulus, and other physical characteristics. Using fluid–structure interaction methods, the impact of different tree species on the wind environment within various tree array layouts is numerically simulated at a wind speed of 14 m/s. In conclusion, the retention layout is most effective in controlling wind speed. Camphor trees perform excellently in reducing wind speed within both retention and enclosure tree array layouts, with wind reduction efficiencies of 16.06% and 14.09%, respectively. Soapberry trees show optimal wind speed reduction in the through layout, achieving 12.31%.