Transient Thermohydraulic Heat Pipe Modeling: Incorporating throhput into the cæsar Environment

Abstract

Abstract. The THROHPUT code, which models transient thermohydraulic heat pipe behavior, is being incorporated into the CBSAR computational physics development environment. The C~ESAR environment provides many beneficial features for enhanced model development, including levelized design, unit testing, Design by ContractTM (Meyer, 1997), and literate programming (Knuth, 1992), in a parallel, object-based manner. The original THROHPUT code was developed as a doctoral thesis research code; the current emphasis is on making a robust, verifiable, documented, component-based production package. Results from the original code are included. THE THROHPUT CODEHeat pipes are structures that transport heat by the evaporation and condensation of a working fluid, giving them a high effective thermal conductivity. Many space-based uses for heat pipes have been suggested, and high temperature heat pipes using liquid metals as working fluids are especially attractive for these purposes. These heat pipes are modeled by the THROHPUT code (THROHPUT is an acronym for Thermal Hydraulic Response Of Heat Pipes Under Transients and is pronounced the same as the word "throughput"). Summary Description of THROHPUTThe THROHPUT code provides a detailed model of the transient, thermohydraulic behavior of liquid metal heat pipes. Currently, it models homogeneous or composite wicks in a cylindrical heat pipe structure. The boundary conditions assumed are: a time-dependent heat input in the evaporator section, zero heat transfer at the outer wall in the adiabatic section, and radiative cooling to a specified ambient temperature in the condenser section. The user specifies the dimensions of the heat pipe and of the wick structure.