The integrated ducted structure significantly enhances the aerodynamic performance of duct–rotor system, reducing noise and enhancing rotor safety. However, in coupled parameters duct are crucial to its characteristics. This study employs a Computational Fluid Dynamics numerical analysis investigate duct–rotor, focusing on related blade’s relative position tip gap. Additionally, our research delves into fundamental mechanisms key parameters, such as blade gap, elucidating their role...

Hydraulic torque converters are prone to cavitation due their high impeller rotational speeds and complex three-dimensional flow characteristics. Since the blades core components of converters, shapes important hydraulic performance Different computational fluid dynamics (CFD) models for a converter were developed simulate internal different pump turbine blade exit angles, influence angles on characteristics field in was investigated. Experimental prototypes produced tested verification. The...

This study investigates the impact of rotor spacing on aerodynamic performance a coaxialcopter. It has been observed that small distance between two rotors can result in significant interaction propellers, consequently affecting rotor's efficiency. Exploiting this characteristic, present research introduces coaxialcopter with variable spacing. Employing finite element numerical simulations, we assess behavior novel configuration. Through comprehensive measurements and analysis its...

Cavitation is a transient phase transition between liquid and vapor, it often occurs in fluid machinery, especially hydraulic torque converter that uses oil as the working medium to transmit speed torque. The complex strongly coupled flow prone cavitation due high rotating high-temperature conditions. seriously affects performance, transmission smoothness, service life of converter. pressure stator under various charging conditions speeds was measured. data on blade were analyzed time domain...

The precise regulation of hinge moment and pitch angle driven by the regulated mechanism is crucial for modulating thrust requirements ensuring stable attitude control in Martian coaxial rotorcraft. Nonetheless, aerodynamic rotorcraft presents time-dependent dynamic properties, posing significant challenges accurate measurement assessment such characteristics. In this study, we delve into detailed characteristics associated with Mars under a spectrum strategies. A robust computational fluid...

The increase in power density of hydrodynamic torque converters (HTCs) leads to a sharp rise temperature within flow channels, affecting the reliability. In order accurately predict thermal effect and distribution characteristics HTC internal viscosity oil, multi-physics computational fluid dynamics (CFD) model is proposed. A specialized test bench was established, macro data were obtained. HTCs with different working conditions wheel sets studied. results indicate that CFD considering...

Hydraulic torque converter is widely used in transmission units as it able to provide variable speed and ratio, isolate vibration, absorb shock. The pursuit of a highly packed power unit requires high capacity/speed converter, consequently resulting higher risk for cavitation severe performance degradation, noise, even failure. Existing models generally focus on water, the empirical parameters are not suitable prediction which utilizes viscosity oil its working medium. This paper focused...

Viscous oils, which are media commonly used for fluid power transmission, characterized by high velocities, temperatures, and pressures when working in components mechanics. The transient nature of viscous oil makes it susceptible to complex operating conditions, result cavitation phenomena can threaten the normal operation safety machinery components. In this study, a three-dimensional computational dynamics model that accounts was developed study characteristics, formation development...

By means of experimental measurement the transient internal flow field and periodic lumped-blade separation analysis method (PLSAM), pressure distribution on a stator blade surface corresponding flow-induced pulsation, as well fluctuation characteristics in torque converter are acquired further analysed. The results show that there both under influence induced while relationship between these fluctuations rotatory angle wheels reveals mechanism pulsation; namely, main cause pulsation lies...

Abstract Traditional forward design method for blade of hydrodynamic torque converter is limited by empirical so that it difficult to produce innovative results. Based on the adjoint sensitivity, an unconventional optimization method, Adjoint Fluid Topology Optimization was proposed. this a directional topological stator carried out as example achieve better ratio performance under stalling condition. Such can irregular with performance. Moreover, flow energy distribution before and after...

<title>Abstract</title> Conventional optimization approaches for torque converters often rely on iterative trial-and-error methods, resulting in inherent limitations and uncertainties. To address these challenges achieve performance based flow characteristics, this study proposes an inverse design method turbomachinery. Introducing a novel index blade loads, denoted as rvt , enables simultaneous both the cascade system field. Furthermore, pump’s driven loads are introduced directional of...

The precise regulation of the hinge moment and pitch angle driven by pitch-regulated mechanism is crucial for modulating thrust requirements ensuring stable attitude control in Martian coaxial rotorcraft. Nonetheless, aerodynamic rotorcraft presents time-dependent dynamic properties, posing significant challenges accurate measurement assessment such characteristics. In this study, we delve into detailed characteristics associated with Mars under a spectrum strategies. A robust computational...

This study investigates the impact of rotor spacing on aerodynamic performance a coaxialcopter and promotes an innovative regulated control strategy for coaxial drone. The present research introduces with variable spacing, employing finite element numerical simulations, we assess behavior this novel configuration. Through comprehensive measurements analysis its across varying spacings from 0.1 R to 1 R, validate effectiveness rotor-spacing enhancing takeoff maneuvers. simulation experiment...

Abstract By means of pseudo lumped-blade simulation method (PLSM), the blade torque vibration in converter under different speed ratios is extracted and analyzed. The result indicates that wheel pulsation induced by flow fluctuation, while mechanism this fluctuation lies continuous switch position pump turbine related to stator. There are mainly two states for stator channel: “pass” “block”. In state, upstream channel aligned downstream inlet. Besides, due influence wake transmitted from...

Abstract Coaxilcopter with variable rotor space can dynamically adjust the parameters such as angle of attack blades through pitch-regulated device, so it and change flight attitude. However, both aerodynamics structure device are complex, some forces generated by will act on in form a hinge moment, which would affect realiablity whole craft. Therefore, coaxilcopter is designed, finite element numerical simulation method promoted to calculate analyze transient aerodynamic loads under...

Abstract The main function of the torque converter pump is to transfer mechanical power into fluid dynamic energy. It has been proved that blade shape, especially camber peak, crucial hydrodynamic performance. However, it remains unclear how this parameter affects internal flow characteristics, and leads difference in Thus, relationship between performance mechanism were explored study. Torque converters with different tested. Meanwhile, corresponding numerical models also established their...

Flying vehicles are considered a promising solution for enhanced transportation; however, existing configurations face limitations in terms of flexibility. The introduction deflection servos has shown to enhance maneuverability and flexibility flying cars, but it also leads an increase roll angle oscillation, thereby posing challenges control. application controllers designed quadrotor UAVs deflection-based is inadequate due structural differences. To address this issue, paper proposes...