| 摘要 |
There is described a method for cooling and sealing of a heat shield element, comprising a main wall with an inner side, which is restricted by side walls or rims, and an outer side, which can be exposed to a hot fluid, and wherein a coolant is introduced into an impingement region of that heat shield element and an impingement flow of said coolant is directed on a surface area of that inner side through a plurality of impingement holes, effecting an impingement pressure drop. In the method discharge flow is metered through a number of discharge holes through said side wall or rims from the inner side to the outer side of the main wall, generating a discharge pressure drop in series with the impingement pressure drop. The impingement pressure drop and the discharge pressure drop are matched to one another so that a required coolant flow is generated which yields a required predetermined heat-transfer coefficient of the main wall. Discharging coolant into the gaps between side opposing walls of neighbouring heat shield elements only allows for an effective sealing against hot gas pingestion. Furthermore, the invention relates to a heat shield element, preferably to a single chamber or double chamber metallic heat shield element, which can be exposed to hot gases. In particular the heat shield element is suitable for being used in a combustion chamber of a gas turbine installation.
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