応用機械工学ジャーナル

概要

Review of Passive Cooling Techniques in Gas Turbine Blades to Enhance the Heat Transfer Rate

Sushil Sunil Gaikwad

In recent years the gas turbines have become an important part of power generating industries. As the demand of power is increasing day by day, the generation of additional power requires a gas turbine to produce more amount of energy per day. In order to achieve this more shaft power needs to be generated per unit time. This means the turbines should operate at higher temperatures of the gas at the inlet (Turbine Inlet Temperature or TiT) to increase the power as well as to enhance the efficiency of the gas turbines. But if the temperature is increased beyond a specific value it may cause the turbine blades to melt and ultimately damage it. In order to prevent this melting and damage, cooling techniques are employed in the gas turbines. There are mainly two types of cooling techniques-Active cooling and Passive cooling. Active cooling relies on external cooling devices which may result in increased power consumption, although it will work effectively in some cases. Passive cooling techniques directly use geometrical modifications to the surfaces of the turbine blades like pin-fins, dimples, passages and so on. In this article we are going to review the passive cooling techniques employed in a gas turbine blade.