English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Loop heat pipes (LHPs) are two-phase heat transfer devices that utilize the capillary force developed in the porous wick to circulate the working fluid. The latent heat can be transferred from a heat source to a radiator by the phase change of the working fluid (Ku, 1999; Maydanik, 2005). LHPs have been used in spacecraft and satellites (e.g., GLAS and SWIFT/BAT; Baker et al., 2004; Ottenstein et al., 2003) to control temperature because LHPs can transfer heat with higher efficiency than other devices and without electricity. Multiple LHPs (MLHPs), which have two evaporators and two condensers in one loop, were proposed to improve the efficiency of traditional LHPs (Ku, 1999; Maydanik, 2005). However, the operation characteristics of MLHPs are complex compared to conventional LHPs, they have not been applied in spacecraft. An experiment on an MLHP with two evaporators and one condenser was reported in 1997 (Bienert et al., 1997), and a test on an MLHP with two evaporators and two condensers was carried out in 2002 (Delil et al., 2003). Miniature MLHPs with flow regulators were experimentally studied in 2008 (Ku et al., 2008). As for simulations of MLHPs, a steady state mathematical model was established in 2004 (Hoang and Ku, 2004), followed by the creation of a transient model (Hoang and Ku, 2005; Hoang and Ku, 2007). Although MLHPs have been studied for 17 years, the mathematical models and flow regulator data are still insufficient, and models need to be developed under a wider range of conditions. In prior studies, the mathematical models were not illustrated in detail, and the discussion of flow regulators was insufficient. In 2014, our group tested an MLHP with a PTFE wick (Okutani et al., 2014) and then confirmed the efficiency of the flow regulator (Chang and Nagano, 2014). The PTFE wick was selected instead of a conventional metal wick because of its low thermal Xinyu CHANG * and Hosei NAGANO* *Department of Aerospace Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan E-mail: chang@prop2.nuae.nagoya-u.ac.jp

Mathematical modeling of multiple evaporators/condensers loop heat pipe operation with flow regulator under various operating conditions