Flow control arrangement

Abstract

Trailing edge coolant flow passages 100 are generally sized and determined by the available width 102 of the trailing edge. In such circumstances it may be difficult to achieve the desired flow control due to the limitations upon casting and moulding of narrow coolant passages within the constraints of that width 102 . The present invention provides flow control features 103, 203 which act to reduce the available cross-sectional area and so provide for flow control and normally like for like reduction in such flow. It will be understood that coolant flow is essentially a parasitic effect upon engine performance, thus reduced coolant flow for desired operational performance has benefits. Due to the reinforcing effect of the flow control features 103, 203 it is possible to also provide wider than previously acceptable coolant flow passages within trailing edges with the reduction in available area provided by the flow control features 103, 203.

1 . A flow control feature for a coolant passage arrangement in a turbine engine, the flow control feature having a lateral presence when positioned within a coolant passage to limit thereby available cross-sectional area for flow within the passage and the lateral presence being shaped for desired aerodynamic effect upon any such flow in use.  
   
   
       2 . A feature as claimed in  claim 1  wherein the flow control feature is symmetrical in a direction to allow symmetry with regard to any flow in a coolant passage.  
   
   
       3 . A feature as claimed in  claim 1  wherein the feature is one of rectangular, triangular, tear-drop and racetrack shaped cross-section.  
   
   
       4 . A feature as claimed in  claim 1  wherein the feature is an insert for subsequent fitting within a coolant passage.  
   
   
       5 . A feature as claimed in  claim 1  wherein the flow control feature is cast with a coolant passage.  
   
   
       6 . A feature as claimed in  claim 1  wherein the aerodynamic effect is to facilitate substantially laminar flow downstream of the feature in use.  
   
   
       7 . A feature as claimed in  claim 1  wherein the aerodynamic effect is to create flow turbulence downstream of the feature to facilitate heat exchange.  
   
   
       8 . A feature as claimed in  claim 1  wherein the control feature is positioned centrally within a coolant passage in use.  
   
   
       9 . A flow control arrangement for a coolant passage in a turbine engine wherein the arrangement includes a flow control feature as claimed in  claim 1 .  
   
   
       10 . A turbine engine incorporating a flow control arrangement as claimed in  claim 9.