Mathematical modeling of the thermal condition of pressurized aircraft compartments

A method for determining the thermal state of the instrument pressurized compartments of the aircraft, based on the use of a mathematical model of the thermal state of the compartments, has been developed. The mathematical model of the air-conditioning compartment is represented by a system of equations of honeycomb thermally insulated skin, ordinary differential equations of convective heat transfer of the inner surface of the thermal insulation of the skin and compartment structures, on-board equipment, air and enthalpy transfer from the air conditioning system. With parametric identification of the parameters of compartments and the air conditioning system, methods developed for solving the direct and inverse problem of heat transfer and determining confidence intervals for parametric identification estimates. Confidence intervals for estimating the coefficients of the nonlinear mathematical model of the thermal state of the compartment are determined by the method of projecting the joint confidence region of estimates onto the coordinate axes of the coefficient space. The research is carried out in accordance with the Airworthiness Standards. The required characteristics of the air conditioning system and the thickness of the honeycomb thermal insulation of the compartment were obtained.
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