A NUMERICAL STUDY OF THE EFFECT OF EXTERNAL ACTION AND OF THE PROPERTIES OF A CAPILLARY-POROUS MATERIAL ON THE CRITICAL MOISTURE-CONTENT INAN EVAPORATION THERMAL PROTECTION SYSTEM

A mathematical model of an evaporation thermal protection system for a thermally thin plate is presented, consisting of a layer of a moistur e-saturated capillary-porous material, a cavity into which a liquid ev aporates, and an opening for vapor to be carried away into the environ ment. A numerical study of the effect of the parameters of the capilla ry-porous material and of external action on the critical moisture con tent and the quantity of liquid displaced from the material is based o n the model. It is shown that an increase in the permeability of the m aterial and a decrease in the diffusion coefficient affect the critica l moisture content in a qualitatively similar manner.