Technical Paper
Steady State Performance Results for a Flexible High-Performance Variable Conductance Heat Pipe
2009-07-12
2009-01-2502
Performance tests and analysis of a new flexible Variable Conductance Heat Pipe (VCHP) design are reported. The unit features a single liquid passage through most of the length and incorporates flexible sections to reduce transverse bending stiffness to less than 175 N/m. A feedthru plate is accommodated to enable installation of the heat pipe in a dual environment. The unit accepts a high heat flux heat input of more than 50 W/cm2 and has a demonstrated thermal conductance of ∼50 W/°C (at 14 W per cm of evaporator length). The demonstrated room temperature heat transport limit is approximately 150 W-m for this 1 cm OD design as configured. The unit was first tested as a Constant Conductance Heat Pipe (CCHP) to validate ammonia charge quantity and heat transport. It was then reworked to include a gas reservoir, and the performance was again validated. The test data was then compared with the thermohydraulic model predictions and shown to be in excellent agreement.