Thermally tunable systems

Abstract

One embodiment of the present disclosure is a unique system. Another embodiment is a unique fastener system. Another embodiment is a unique gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engines, fastener systems and other systems. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.

What is claimed is: 
     
         1 . A system for securing a first attachment location to a second attachment location, comprising:
 a first member having a first coefficient of thermal expansion, a first attachment feature, and a first interface feature, wherein the first attachment feature is configured for attaching the first member to the first attachment location;   a second member having a second coefficient of thermal expansion that is higher than the first coefficient of thermal expansion; and having a second interface feature and a third interface feature, wherein the first interface feature and the second interface feature are configured for engagement with each other, and are configured to transmit an axial load between the first member and the second member; and   a third member having a third coefficient of thermal expansion that is lower than the second coefficient of thermal expansion; and having a second attachment feature and a fourth interface feature, wherein the second attachment feature is configured to attach the third member to the second attachment location; and wherein the fourth interface feature and the third interface feature are configured for engagement with each other, and are configured to transmit an axial load between the second member and the third member.   
     
     
         2 . The system of  claim 1 , wherein in an installed condition, the first attachment feature is attached to the first attachment location, and the second attachment feature is attached to the second attachment location; and wherein in the installed condition, the first member and the third member are loaded in tension, and the second member is loaded in compression. 
     
     
         3 . The system of  claim 1 , wherein in an installed condition, the first attachment feature is attached to the first attachment location, and the second attachment feature is attached to the second attachment location; wherein in the installed condition and at an operating temperature, the first member and the third member are loaded in tension; and wherein in the installed condition at the operating temperature, the second member is loaded in compression. 
     
     
         4 . The system of  claim 1 , wherein the first member, the second member, and the third member are arranged in a relationship wherein the second member is disposed proximate the first member and the third member is disposed proximate the second member. 
     
     
         5 . The system of  claim 1 , wherein the first member includes a first member body, the second member includes a second member body, and the third member includes a third member body. 
     
     
         6 . The system of  claim 5 , wherein at least one of the first member body, the second member body, and the third member body is a cylindrical shaft. 
     
     
         7 . The system of  claim 5 , wherein the first member body is nested within the second member body; and wherein the second member body is nested within the third member body. 
     
     
         8 . The system of  claim 5 , wherein the first member and the third member are configured for relative sliding motion as with respect to each other along a longitudinal axis of the system. 
     
     
         9 . The system of  claim 1 , wherein the first member and the third member are configured for sliding relative motion as with respect to each other along an axis extending between the first attachment feature and the second attachment feature. 
     
     
         10 . A system for positioning a first structure relative to a second structure, comprising:
 a core shaft having a first coefficient of thermal expansion, a first abutment feature, and a first interface feature, wherein the first abutment feature is configured for transmitting loads and/or motion between the core shaft and the first structure;   an inner shell having a second coefficient of thermal expansion that is different than the first coefficient of thermal expansion; and having a second interface feature and a third interface feature, wherein the first interface feature and the second interface feature are configured for engagement with each other, and are configured to transmit an axial load between the core shaft and the inner shell; and   an outer shell having a third coefficient of thermal expansion that is different than the second coefficient of thermal expansion; and having a second abutment feature and a fourth interface feature, wherein the second abutment feature is configured for transmitting loads and/or motion between the outer shell to the second structure; and wherein the fourth interface feature and the second interface feature are configured for engagement with each other, and are configured to transmit an axial load between the inner shell and the outer shell.   
     
     
         11 . The system of  claim 10 , wherein the first, second, and third coefficients of thermal expansion are selected to increase an axial distance between the first abutment feature and the second abutment feature with increasing temperature. 
     
     
         12 . The system of  claim 10 , wherein the first, second, and third coefficients of thermal expansion are selected to maintain an axial distance between the first abutment feature and the second abutment feature with increasing temperature. 
     
     
         13 . The system of  claim 10 , wherein the first, second, and third coefficients of thermal expansion are selected to decrease an axial distance between the first abutment feature and the second abutment feature with increasing temperature. 
     
     
         14 . The system of  claim 10 , wherein the first, second, and third coefficients of thermal expansion are selected to achieve a desired axial distance between the first abutment feature and the second abutment feature at a desired operating temperature. 
     
     
         15 . The system of  claim 10 , wherein the core shaft and the outer shell are configured for sliding relative motion as with respect to each other along a longitudinal axis of the system. 
     
     
         16 . The system of  claim 10 , wherein the core shaft is not hollow. 
     
     
         17 . The system of  claim 10 , wherein the inner shell is disposed within the outer shell; and wherein the core shaft is disposed within the inner shell. 
     
     
         18 . The system of  claim 10 , wherein in an installed condition, the first abutment feature is coupled to the first structure, and the second abutment feature is coupled to the second structure; and wherein in the installed condition, the outer shell and the core shaft are loaded in tension, and the inner shell is loaded in compression. 
     
     
         19 . The system of  claim 10 , wherein in an installed condition, the first abutment feature is attached to the first structure, and the second abutment feature is attached to the second structure; wherein in the installed condition and at an operating temperature, the core shaft and the outer shell are loaded in tension; and wherein in the installed condition at the operating temperature, the inner shell is loaded in compression. 
     
     
         20 . A gas turbine engine, comprising:
 a thermally tunable system, including:   a first abutment feature configured to transmit loads between the thermally tunable system and a first structure;   a second abutment feature spaced apart from the first abutment feature and configured to transmit loads between the thermally tunable system and a second structure; and   means for positioning the first abutment feature and /or the second abutment feature relative to the other, wherein the means for positioning is tunable to achieve a desired change in a distance between the first abutment feature and the second abutment feature with a change in temperature of the thermally tunable system.