اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدImprovement in the performance of multilayer insulation technique and impact in the rare physics search experiments
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Providing thermal insulation to systems at very low temperature from surroundings, involves blocking the transport of thermal energy regular or enhanced, taking place through radiative, conductive and convective processes. For instance, the enhancement of radiative heat transport that takes place by infra red or far infra red light at low temperature is due to diffractive propagation. The wavelength of light in this part of the spectrum usually lie in the range of mm to cms. Hence it can get bent across an obstacle while propagating forward. Apart from radiative, the convective and conductive processes also get affected due to appearance of non linearities in the modes of lattice vibrations and anomalies in material transport due to the appearance of vorticity and turbulence in the intervening media. The Multilayer insulation technique has offered a robust thermal protective mechanism to provide proper insulation to the cold walls of the cryostats from the heat of the surroundings. This work is focused on the estimation of performance and efficiency of the MLI technique as well as exploration of its versatile applicability. Three different spacer materials such as Dacron, Glass tissue, and Silk net with radiation shields are selected for the intervening medium in the present study. This article explores the thermal performance of MLI system by changing the physical parameters, varying the geometry of the radiation shields perforation styles of radiation shields and by analyzing the effect of arrangement of radiation shields on the conduction heat load. This analysis is concluded by studying the possibility of using MLI technique in the health sector by reducing the evaporation rate of liquid Oxygen during pandemic situations e.g. in COVID19.
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Multilayer insulation (MLI) is an important technique for the reduction of radiation heat load in cryostats. The present work is focused on investigation for the selection of suitable reflective layer and spacer material in MLI systems. In our analys
is, we have selected perforated double-Aluminized Mylar (DAM) with Dacron, unperforated DAM with Silk-net and perforated DAM with Glass-tissue for their evaluation as the reflective layer as well as spacer materials in MLI technique. Current work would discuss the calculation of the effect of layer density and the number of layers on the heat load. Knowing the key parameters of MLI, we have compared the heat load generation in spherical as well as cylindrical cryostats and the effect of layering near and outer surface on the heat load.
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