Temperature control method in canopy fatigue test

Abstract

The present invention discloses a temperature control method in a canopy fatigue test, belonging to the technical field of canopy fatigue tests. The method comprises the following steps of: the step 1, arranging temperature sensors and a current meter; the step 2, setting the position of a second temperature sensor (12) as a control point and setting a relation of the control point temperature anda load spectrum temperature; the step 3, performing loading according to the relation of the control point temperature and the load spectrum temperature set in the step 2, and obtaining the highest temperature point P at the surface of a test piece and temperatures of the point P in all the moments in a loading time; the step 4, comparing the temperatures of the point P in all the moments with atemperature load spectrum to determine whether a generated error meets a test error requirement or not; and the step 5, substituting a mapping relation after correction into the relation of the control point temperature and the load spectrum temperature to perform iteration operation until the test error requirement is met. The temperature control method in the canopy fatigue test only needs to perform several iteration correction when the relation of the inlet temperature and the temperature of the highest temperature point is debugged, and is clear in principle and simple in operation.

Description

technical field [0001] The invention belongs to the technical field of canopy fatigue tests, and in particular relates to a temperature control method in the canopy fatigue test. Background technique [0002] During flight, the aircraft will be subjected to aerodynamic heating, resulting in a large temperature gradient on the inner and outer surfaces of the canopy, which makes the canopy glass prone to fatigue damage. As the Mach number of the aircraft increases, more aerodynamic heat will be generated on the outer surface of the canopy, and the performance of the canopy will directly affect the safety of the aircraft and pilots. Fatigue life of the metal frame. [0003] The heating and loading test of the canopy uses the principle of convective heat transfer to control the surface temperature of the canopy. Before the test, a debugging test needs to be carried out. Several thermocouples are uniformly pasted on the debugging part along the course and span of the plexiglass...

AI Technical Summary

Problems solved by technology

After the formal test piece is installed, it is first necessary to determine the position of the control point on the test piece according to the position of the temperature control point of the test piece. Doing so may cause a deviation in the position of the highest temperature point, making the non-highest temperature position the control point, resulting in test safety. Then paste thermocouples or fixed platinum resistors at the temperature control points. If the thermocouples are installed by glue, the plexiglass of the canopy will be corroded by the adhesive in the long-term fatigue test; if the platinum resistors are used The method is in contact with the surface of the canopy. In the heating and loading test, under the action of the pressure load in the cabin, there will be a depression between the platinum resistor and the plexiglass of the canopy, which will eventually cause the canopy to be damaged to varying degrees and affect the test. Precision and Safety

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