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The nonlinear dynamic analysis has been carried out to investigate the dynamic behavior of a perfectly balanced horizontal rotor (HR)-tilting pad journal bearing (TPJB) system and perfectly balanced vertical rotor (VR)-tilting pad journal bearing (TPJB) system by computing frequency response of both the systems. To do so, governing differential equations (GDEs) of motion for HR-TPJB system and VR-TPJB system has been derived and they were solved by finite element method (FEM). The GDE of motion of both systems have been combined to form a unit set. This unit set represents the HR/VR-TPJB system. Implementation of computational numerical integration technique has been employed to solve equations of motion of both the systems which has been solved using the MATLAB® ODE-15s solver. Indigenous MATLAB® program has been created to compute the above-mentioned frequency response of the system efficiently. Time-Amplitude Response and Frequency-Amplitude Response with Phase at both the TPJB's and rigid disc locations have been computed by Fast Fourier Transform (FFT). The dynamic behavior of the perfectly balanced HR-TPJB and VR-TPJB systems have been analyzed for different rotor speeds. The results and discussions on the nonlinear dynamic behavior of perfectly balanced HR-TPJB and VR-TPJB systems operating at low and high rotor speed have been explained which indicates HR-disc is more unstable than HR-journal inside identical 4-pad TPJBs at low rotational speed (1500 rpm). The frequency response of both HR-TPJB system and VR-TPJB system at low speed (1500 rpm) shows that peak amplitude appeared much before in VR than HR, which indicates even in low rotational speed, VR-TPJB system is more unstable than HR-TPJB system. Results demonstrated that the balanced VR operated at high speed (6000 rpm) is more prone to instabilities than its horizontal counterpart (HR-TPJB system) at the same speed (6000 rpm). [ABSTRACT FROM AUTHOR]

The new generation of condition monitoring and diagnostics system plays an important role in efficient functioning of power plants. In most of the rotating machine, defects can be detected by such a system much before dangerous situation occurs. It allows the efficient use of stationary on-line continuous monitoring system for condition monitoring and diagnostics as well. Condition monitoring of turbine shaft can not only reduce expenses of maintenance of turbo generator of power plants but also prevents likely shutdown of plant, thereby increases plant load factor. Turbo visionary parameters are essential part of health diagnosis system of turbo generator. Particularly steam pressure, steam temperature and lube oil temperature are important parameters to monitor because they are having much influence on turbine shaft vibration and also governing systems are available for change values of those parameters. This paper includes influence of turbo visionary parameters i.e., steam temperature, steam pressure, lube oil temperature, turbine speed and load on turbine shaft vibration at turbo generator at 195 MW unit-6,Kota Super Thermal Power Station by measuring vibration amplitude and analyze them in MATLAB. [ABSTRACT FROM AUTHOR]