A.I. Ulitenko, V.V. Klimakov, A.V. Molchanov, M.V. Chirkin

Problem of internal temperature field smoothing is considered in regard to strapdown inertial navigation systems (SINS). High areal density of heat generation elements and low efficiency of heat transport restrict heat removal with power value about dozens of Watts in SINS with laser gyros and quartz accelerometers. The paper deals with the way search providing stability and uniformity of the temperature field inside SINS. The thermal condition is investigated experimentally and the temperature field inside SINS is registered. Bifurcation of heat flows inside system is observed that reduces the field reliability. Tolerable limit of temperature difference between inertial sensors and external housing is defined. However the achievement of the performance objectives is impossible if heat removal is provided by heat conduction and natural convection only. There designed the flexible gas-regulating heat pipe integrated in strapdown inertial navigation system for the purpose stability and uniformity of the temperature field inside inertial measurement unit. Compatibility of the heat pipes and laser gyros with mechanical dither is justified. The heat pipe developed reduces the temperature field uniformity by order of magnitude and makes it possible automatic controlling the temperatures of inertial sensitive elements in dependence on the ambient temperature.