Thermocouples for high temperature applications

A turbomachine, comprising:

• a compressor section;
• a combustor section;
• a turbine section;
• and
• a thermocouple disposed at least partially in one of the compressor section, the combustor section, or the turbine section, the thermocouple comprising:
• a vessel formed from a dielectric material, the vessel defining a first chamber and a second chamber, the first chamber and second chamber being in fluid communication;
• a first thermoelement disposed in the first chamber, the first thermoelement being formed from a first thermoelectric material, wherein the first thermoelement defines a first outer diameter;
• a second thermoelement disposed in the second chamber, the second thermoelement being formed from a second thermoelectric material different from the first thermoelectric material, wherein the second thermoelement is a liquid at operating temperatures of the thermocouple, and wherein the second thermoelement defines a second outer diameter;
• and
• a junction passage defined in the vessel and providing for the fluid communication between the first chamber and the second chamber, wherein the junction passage defines a third diameter that is less than at least one of the first outer diameter or the second outer diameter, the third diameter being sized such that hydrostatic tension between the first and the second thermoelectric materials allows for contact between the first and the second thermoelectric materials but prevents mixing of the first and the second thermoelectric materials.