Two Closed Loop Pulsating Heat Pipes (CLPHPs) are tested on board REXUS 18 sounding rocket in order to obtain data over a relatively long microgravity period (approximately 90 s). The CLPHPs are partially filled with FC-72 and have, respectively, an inner tube diameter larger (3 mm) and slightly smaller (1.6 mm) than the critical diameter evaluated in static Earth gravity conditions. On ground, the small diameter CLPHP effectively works as a Pulsating Heat Pipe (PHP): the characteristic slug and plug flow pattern forms inside the tube and the heat exchange is triggered by thermally driven self-sustained oscillations of the working fluid. On the other hand, the large diameter CLPHP works as a two- phase thermosyphon in vertical position and doesn't work in horizontal position: in this particular condition, the working fluid stratifies within the device as the surface tension force is no longer able to balance buoyancy. Then, the idea to test the CLPHPs in reduced gravity conditions: as the gravity reduces the buoyancy forces becomes less intense and it is possible to recreate the typical PHP flow pattern also for larger inner tube diameters. This allows to increase the heat transfer rate and, consequently, to decrease the overall thermal resistance. Even though it was not possible to experience low gravity conditions due to a failure in the yoyo de-spin system, the thermal response to the peculiar acceleration field (hyper-gravity) experienced on board are thoroughly described.

Pulsating Heat pipe only for Space (PHOS): Results of the REXUS 18 sounding rocket campaign

FIORITI, DAVIDE;Nannipieri, P.;FILIPPESCHI, SAURO;DI MARCO, PAOLO;FANUCCI, LUCA;MAMELI, MAURO;
2015-01-01

Abstract

Two Closed Loop Pulsating Heat Pipes (CLPHPs) are tested on board REXUS 18 sounding rocket in order to obtain data over a relatively long microgravity period (approximately 90 s). The CLPHPs are partially filled with FC-72 and have, respectively, an inner tube diameter larger (3 mm) and slightly smaller (1.6 mm) than the critical diameter evaluated in static Earth gravity conditions. On ground, the small diameter CLPHP effectively works as a Pulsating Heat Pipe (PHP): the characteristic slug and plug flow pattern forms inside the tube and the heat exchange is triggered by thermally driven self-sustained oscillations of the working fluid. On the other hand, the large diameter CLPHP works as a two- phase thermosyphon in vertical position and doesn't work in horizontal position: in this particular condition, the working fluid stratifies within the device as the surface tension force is no longer able to balance buoyancy. Then, the idea to test the CLPHPs in reduced gravity conditions: as the gravity reduces the buoyancy forces becomes less intense and it is possible to recreate the typical PHP flow pattern also for larger inner tube diameters. This allows to increase the heat transfer rate and, consequently, to decrease the overall thermal resistance. Even though it was not possible to experience low gravity conditions due to a failure in the yoyo de-spin system, the thermal response to the peculiar acceleration field (hyper-gravity) experienced on board are thoroughly described.
2015
Creatini, F.; Guidi, G. M.; Belfi, F.; Cicero, G.; Fioriti, Davide; Di Prizio, D.; Piacquadio, S.; Becatti, G.; Orlandini, G.; Frigerio, A.; Fontanesi, S.; Nannipieri, P.; Rognini, M.; Morganti, N.; Filippeschi, Sauro; DI MARCO, Paolo; Fanucci, Luca; Baronti, F.; Mameli, Mauro; Manzoni, M.; Marengo, M.
File in questo prodotto:
File Dimensione Formato  
IOP_Uit 2015_ Phos Team.pdf

accesso aperto

Descrizione: Creatini, F., Guidi, G.M., Belfi, F., Cicero, G., Fioriti, D., Di Prizio, D., Piacquadio, S., Becatti, G., Orlandini, G., Frigerio, A., Fontanesi, S., Nannipieri, P., Rognini, M., Morganti, N., Filippeschi, S., Marco, P.D., Fanucci, L., Baronti, F., Mameli, M., Manzoni, M., Marengo, M. Pulsating Heat pipe only for Space (PHOS): Results of the REXUS 18 sounding rocket campaign (2015) Journal of Physics: Conference Series, 655 (1), art. no. 012042
Tipologia: Versione finale editoriale
Licenza: Creative commons
Dimensione 1.35 MB
Formato Adobe PDF
1.35 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11568/769444
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 12
  • ???jsp.display-item.citation.isi??? 12
social impact