Optimization And Control For Aircraft Ground Deicing Parameters

Ice and snow weather have always been one of the important factors that threaten the safety of aircraft and cause large-scale delays.The existing aircraft ground deicing system equipment has solved safety problems such as secondary icing to a certain extent.However,with the high-density operation of flights becoming the norm,the accuracy and response speed of deicing parameters cannot meet the actual needs of airport,and there is still inadequate lack of theoretical technlogies support for deicing mechanism,parameter configuration,operational-planning and operation coordination.Given the aforementioned background,deicing parameter optimization and control methods including configuration,operational deicing and operation are studied and integrated applications are carried out.To solve the ambiguous of icing characteristics and deicing mechanism,the motion and icing characteristics of supercooled water droplets under the control volume constraint are analyzed.The mass,momentum and energy conservation equations in the typical calculation domain of deicing process are established.Considering the heat loss and heat transfer of deicing fluid injection,a thermodynamic model for the transient deicing process is constructed.The evolution regulation of temperature and thickness for ice accretion surface is obtained through experiments,which realize the mapping from ice accretion state to deicing configuration parameters.Aiming at the precise configuration of deicing fluid temperature,concentration,injection flow,pressure and other parameters,a correlation coupling graph model of deicing configuration parameters is constructed based on the quantitative relationship between deicing time and holdover time.The configuration parameter optimization model is established by targeting time safety margin and deicing fluid consumption.The Lagrangian relaxation method is introduced to simplify complex constraints and the Levenberg Marquardt algorithm is applied to solve the problem.The effectiveness of the model is proved by experiments,which realize the generation of deicing configuration parameters under different meteorological environments.For the fine planning of parameters such as the number of deicing nozzles,motion speed,angle,operational amplitude,and frequency,a multi-objective optimization model of operational parameters is established and a feasible solution domain is constructed by Lagrangian relaxation algorithm.The identification method of icing state evolution based on the subspace method and the correction mechanism of operation parameters are studied.The deicing operational control methods are designed respectively based on state consistency.The feasibility of the method is verified by simulation,which realize the safe operation of the deicing nozzle based on the configuration of a single aircraft.Arranging the precise coordination of parameters such as the state and time slot of deicing process on the airport scene,the spatiotemporal dynamic Bayesian network model is constructed.The deicing operation progress dynamic prediction method is studied based on conditional probability density.The deicing operation parameter optimization model based on multi-agent negotiation and the optimized method are designed.The cooperative control method for deicing operation is designed based on the model predictive control technology.The rationality of the method is demonstrated through simulation,which realize the balanced operation for multiple aircraft deicing processes.By this dissertation,the requirements of aircraft ground deicing parameters optimization and control are systematically analyzed.The configuration,deicing and operation optimization & control modules and interactive interfaces are designed in combination with the interaction mechanism among deicing parameters.Relying on the equipment configuration and location distribution of the deicing system in a large domestic hub airport,the integrated application verification is carried out.Through the test and application,the parameter control ability of deicing parameter optimization and control method is verified in the centralized deicing mode,which further improve airport ground deicing safety performance and overall efficiency.