The spherical pump is a totally new hydraulic concept, with piston and hydrostatic bearing, in order to eliminate the direct contact between cylinder cover. In this paper, governing Reynolds equation under coordinates has been solved bearing characteristics are systematically investigated. operating sensitivities of proposed respect radius, film beginning angle, ending thickness, temperature, s...

A squeeze film damper (SFD) is a commonly used component in aeroengine support structures. However, eccentric SFDs are often employed practical applications. Existing research this field has mainly focused on simple rotor models and frequency-domain solution techniques. In study, system tester with without an SFD was built, simulation model based the finite element method fixed interface modal ...

The research background is the elastic ring squeeze film damper. Four contact pressure models were established by analyzing structural characteristics and movement, combined with sliding bearing theory, including parameters eccentricities. Multi-structure multi-interval dynamic boundary conditions selected actual structures. Simpson, polynomial, integrated methods extended Booker formulas. By c...

A frequency domain system modelling technique is developed for mechanical systems. The technique is derived from Tellegen's Theorem for electrical networks and is applied to discrete mechanical systems. The elements are modelled in terms of their mechanical impedances. A global system model is assembled from the constitutive impedances. The global system model is used to determine the model exa...

Building Heating, Ventilation and Air Conditioning (HVAC) system maintain comfortable indoor environment by supplying processed air to each terminal precisely through duct system. Testing, Adjusting and Balancing (TAB) plays critical role in achieving desired air distribution. Traditional TAB method is inaccurate and inefficient due to its trailand-error natural, which forces people to pay high...

Rolling bearing and squeeze film damper will introduce structural nonlinearity into the dynamic model of aeroengine. Rubbing occur due to clearance reduction design engine. The coupling fault make engine present rich vibration responses. This paper aims analyze nonlinear behavior whole aeroengine including rolling under rubbing fault. Firstly, a turboshaft with support is established; force, oi...

This paper presents an application of a nonlinear magnetic levitation system to the problem of efficient active control of mass-spring-damper mechanical systems. An output feedback control scheme is proposed for reference position trajectory tracking tasks on the flexible mechanical system. The electromagnetically actuated system is shown to be a differentially flat nonlinear system. An extende...