Japan Aerospace Exploration Agency

Comparative Analysis of Ion and Electron Contributions to Ionospheric Ionization at Auroral and Subauroral Latitudes

Abstract Electron and proton precipitation into the nightside ionosphere is a key process in magnetosphere–ionosphere coupling. Although auroral electron precipitation at –10 keV is traditionally considered the main driver of auroral emissions, recent studies show that keV electr...

Characteristics of tropical clouds with strong updrafts revealed by Doppler-velocity measurements from EarthCARE/CPR

Abstract. Updrafts within clouds are important for the climate system, yet global assessments have traditionally relied on indirect proxies. The EarthCARE satellite's 94 GHz Cloud Profiling Radar (CPR) provides the first global, spaceborne Doppler velocity (Vd) profiles of clouds...

Experimental Development of Gaseous Propellant Mono-Cylindrical Rotating Detonation Engine Film Cooling

Thermal management remains one of the critical challenges in the advancement of rotating detonation engine (RDE) technology for practical propulsion applications. To facilitate progress in this field, this study investigates the use of gaseous film cooling via axial injectors, ai...

Impact of Horizontal Tail Position on Turbulence Transition Around Vertical Tail

The research and development of natural laminar flow (NLF) wing designs can minimize airframe drag. This investigation extends to the design of NLF vertical tails for a reference subsonic civil aircraft under cruise conditions. Although parameters unrelated to design are treated...

Fatigue behavior of ultrasonically welded CF/PPS single-lap joints compared with bulk PPS using entropy-based finite element analysis

In this study, carbon-fiber-reinforced polyphenylene sulfide (CF/PPS) laminates were joined by ultrasonic welding using a PPS interlayer to form single-lap joints, and their temperature-dependent fatigue behavior was investigated within an entropy-based fracture framework. A fati...