| Based on the characteristics of seasonal breeding of goose,the gradual maturation of goose anti-season breeding technology to achieve a balanced production throughout the year to make up for the market vacancy,however,goose production hatching also on the internal quality requirements in summer.In rencently year the breeding season the goose sheds all use fans-evaporative pad ventilation mode,although it can realize the hot summer of goose s ventilation cooling effect,the survey found that goose breeding performance decreased with the expansion of production scale,which is mainly due to the decrease of the egg production rate of the goose and the fertilization of the eggs.Based on the analysis of goose production performance and hatching performance decline in addition to farm density is not reasonable cause,it is more important that the goose sheds ventilation system,temperature and humidity index standards and the existing incubator can not simulate goose natural incubation conditions.In this paper,we discuss the problems such as the uneven distribution of airflow in the goose breeder's goose in the south of China,the high temperature and high hygiene and the lack of incomplete incubation of the incubator,on the one hand,using computational fluid dynamics(CFD)technique to evaluate goose s flow field analysis,put forward in the inner add volume optimization design method of membrane structure and validation;On the other hand,by increasing the incubator flip Angle as well as the design of egg tray for further simulate the natural incubation conditions.And the incubation performance of the incubator before and after the transformation was tested and compared.The results of this study can provide the theoretical basis and reference function for the future environment control and optimization design of China's goose house and the internal environment of incubator control.The main conclusions are as follows:1.A three-dimensional steady simulation of the airflow field in the goose house was carried out by using ANSYS Fluent15.0 software.The simulation results show that the goose house in mechanical ventilation having a large number of airflow diffusion located above it and the ventilation effect of the ground geese was obstructed.The velocity of the airflow in the majority of the goose house is less than 0.4 m/s,and the larger area below the middle position shows a wind speed of only 0.2 m/s,and the distribution of the air flow in the house is not uniform.Comparison between simulations and measurements for the 40 test points of wind speed showed that the RMSB,maximum absolute error and average relative error was 0.152m/s,0.29m/s and 2.04%,respectively.It proved that the CFD method is reliable to estimate the distribution of air velocity in the goose house.2.In order to decrease the non-uniform flow coefficient and increase the range of air flow under the goose house.So put forward that the effective ventilation efficiency of the goose house can be improved by adding more of the stretching film structure as well as consistent with the inclined angle of the airflow direction that change the air flow optimization.The validated CFD model was then used to get the optimal combination scheme of 27 different construction cases:In the 42-meter-long goose house,we find that when 10 roll films are installed in the shed,and the angle between roll film and the vertical direction of girder is 60 with maximum drop height of 1.2 meters,the ventilation in the shed has the highest efficiency and its air distribution is more homogeneous,and this simulation is concluded to be the optimal one.hrough in-situ test,40 points are compared before and after the transformation of the wind speed value,the test results show that:after transforming averaged wind velocity increased by 0.527m/s,and the airflow uniformity coefficient decreased by 32.2%.3.The ventilation efficiency of goose house improvement based on the comparison between goose house before and after the transformation of bacteria inside,the change of temperature and humidity.The comparative results show that in the mechanical ventilation model the total bacteria,Staphylococcus aureus and Escherichia coli number were significantly reduced by adding more of the stretching film structure of goose house,and compared to the conventional goose house the dormitory daily temperature is reduced by 0.23 ?.More ande more,it reduce bacteria and alleviate the indoor high temperature and humidity phenomenon by increasing air flow of goose house.4.In this paper,the incubation efficiency of' the incubator of two different turning angles in the goose was compared with taking Yangzhou goose eggs as test object.The new incubator was improved by changing the egg rack and the egg tray with the turning angle of 140 °,which was compared with the traditional incubator only 86 degree turn angle.The incubation rate increased by 2%~3%,the hatching rate of the preserved eggs increased by 1%~3%.and the hatching rate increased by about 4%,The results showed that the increase of the incubator angle was more favorable embryonic development. |
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