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• An energy-recovery system for poultry houses was designed and tested. • 13.5% of the energy used for ventilation fans could be recovered. • The reduction of GHG emissions is estimated to be 3.01gCO2eq/egg∙year. • The system energy and GHG payback time is 3.36 years and 1.17 years, respectively. New and renewable energies are being applied in the field of livestock farming in order to reduce the increasing energy demand and to some extent provide potential alternative profits for producers. In this study, a preliminary ventilation energy-recovery system for poultry houses was investigated. The air flow that generated by the ventilation fans was accelerated by a flow-convergence configuration and the wind turbine located at the outlet of the flow tunnel was applied to recover the energy together with other electronic components. A maximum of 270 W power output from the wind turbine was steadily recorded for this small-scale experimentally-oriented system recovering 13.5 % of the energy used for ventilation. Meanwhile, about 2074kWh renewable energy per year could be produced by the system, accounting for about 10.2% of total energy requirement for poultry farming and reducing approximately 3.01 g C O 2 e q / e g g ∙ y e a r greenhouse gas emissions. Furthermore, a 3.7 % reduction of volumetric ventilation rate was also observed due to the additional pressure load from the wind turbine and no apparent difference in the power consumptions of ventilation fans was found. Furthermore, a life cycle assessment (LCA) was also performed in order to quantify the impacts of applying this system on the environment during its lifespan from 'cradle to grave'. It was demonstrated that the energy and greenhouse gas payback time were 3.36 years and 1.17 years respectively, demonstrating a 'green' and environmentally-friendly system considering the lifespan of the system was 20 years. This study suggests new ideas for the future design of poultry houses combining renewable energy and power generation technology, which is technically and environmentally feasible. [ABSTRACT FROM AUTHOR]

• It is possible to use intelligent fusion algorithm to plan temporary takeoff/landing site's location for the pesticide spraying helicopter. • The location obtained by intelligent fusion algorithm is more reasonable than that planned by manual empirical method. • The optimal temporary takeoff/landing site's location is usually at the closest vertical distance to the best dispatch route. • By planning takeoff/landing site's location, the length of dispatch routes can be reduced, thereby saving operational costs and increasing operational efficiency. Planning the temporary takeoff/landing site's location (TTSL) is an essential task faced by helicopter spraying pesticide operations in the forest. However, neither a scientific theoretical model nor a planning method do exist to address this issue. In this study, a mathematical model for a helicopter's TTSL planning is constructed, and an intelligent fusion algorithm (IWOA-IACO-CLC) is proposed based on the improved whale optimization algorithm (IWOA), improved ant colony optimization (IACO) algorithm, and combinatorial logic classifier (CLC). The fusion algorithm first adds a memory function and Lévy flight disturbance strategy to the whale optimization algorithm, which is used to enhance the global search capability of TTSL. Subsequently, the movement strategy of IACO is modified to a lateral movement within the forest and longitudinal movement between forests to calculate the fitness of the IWOA. Finally, the CLC is used to control the feasible domain of TTSL based on the idea of penalty function. In this setting, five Chinese planted forests were employed for route planning experiments, and the dispatch route length, spraying route length, and extra coverage rate obtained by the intelligent fusion algorithm and the artificial empirical method were analyzed. The results reveal that the IWOA-IACO-CLC algorithm achieves the optimal solution, and the five planned TTSL are more reasonable than those obtained by the artificial empirical method. The dispatch route is shortened by 13.26%, 3.27%, 13.40, 39.67% and 30.47%, the spraying route is shortened by 1.94%, 0.22%, 0.47%, 0.91% and 0.28%, and the extra coverage rate is decreased by 29.15%, 24.92%, 14.63%, 25.99% and 8.24%, respectively. Furthermore, the proposed mathematical model and intelligent fusion algorithm achieve the TTSL planning, while the rational TTSL planning reduces the dispatch route length and the operation cost. This study provides a theoretical basis for the TTSL planning of aerial spray helicopters, as well as a technical reference for the realization of smart forestry. [ABSTRACT FROM AUTHOR]

Highlights • Turbulence flow contributes to the excessive convective heat losses for the birds. • Uniform indoor air movement reduce the temperature at the end of the poultry house. • Side-wall air inlets placed at the middle of the house reduce the temperature at the end of the house. • Side-wall windows have strong effects on the indoor environmental parameters. Abstract Ventilation system is crucial for poultry houses to control the indoor climate and air quality. The tunnel ventilation system is widely applied for large-scale poultry buildings in China but only limited scientific researches regarding the flow pattern, temperature distribution and design criteria are available in the literature. Thanks to the fast development of computer technology, Computational Fluid Dynamics (CFD) techniques were used in present study to investigate the indoor air movement, air temperature and relatively humidity. A three-dimensional CFD model was built according to the real dimensions of a laying hen house and the model was validated by comparing the simulation results with the field measurements at 30 positions. Meanwhile, statistical analysis was performed to determine the differences between different boundary conditions regarding the agreement between measured and CFD simulated results. Optimization of air inlet configurations was performed by using the validated CFD model and it was found that the uniformity of indoor air movement could prevent excessive local convective heat losses and reduce the temperature at the end of the house. Furthermore, the air inlets placed at the middle of the side wall could significantly reduce the high temperature expected at the end of the building without using extra energy, which is especially important for large-scale poultry farms with long buildings. The performance of side-wall windows was also examined and preliminary guidance was provided to effectively regulate the indoor climate by using these windows with the help of environmental monitoring systems. The present study contributes to the understanding and design of the tunnel ventilation system used in poultry houses. [ABSTRACT FROM AUTHOR]

• High concentrations of bio-aerosols are expected at the rear part of the tunnel-ventilated houses. • Turbulent flow resulting from ventilation configuration enhances the dispersion of bio-aerosols. • Local disturbed flow region contributes to the local high concentrations of bio-aerosols. • Small-scale (≤ 10 μ m) bio-aerosols have similar dispersion and deposition behavior in poultry houses. Bio-aerosol concentrations in poultry houses must be controlled to provide adequate air quality for both birds and workers. High concentrations of airborne bio-aerosols would affect the environmental sustainability of the production and create environmental hazards to the surroundings via the ventilation systems. Previous studies demonstrate that several factors including the age of the birds, the housing configuration, the humidity and temperature would strongly affect the indoor concentration of bio-aerosols. However, limited studies are performed in the literature to investigate the bio-aerosol dispersion pattern inside poultry buildings. In order to fill a gap of the understanding of the bio-aerosol dispersion behavior, experimental measurements of the indoor bio-aerosol distribution are performed in a tunnel-ventilated poultry house in this paper. Meanwhile a three-dimensional computational fluid dynamics (CFD) model is built and validated to further investigate the effect of flow pattern, turbulence and vortex on the dispersion and deposition of the bio-aerosols. Furthermore, bio-aerosols with various diameters are also examined in the CFD model. It is found that higher concentrations of bio-aerosols are detected at the rear part of the house and strong turbulent flow resulting from the ventilation inlets enhances the diffusion and dispersion of bio-aerosols. Local vortex or disturbed flow is responsible for higher local concentration due to the re-suspension of settled bio-aerosols, which suggests that careful attentions should be paid to these locations during cleaning and disinfection. Results from present study contribute to the optimization of design and operation of the poultry houses from the standing point of reducing airborne bio-aerosol concentrations. [ABSTRACT FROM AUTHOR]