11 research outputs found

    Experimental Investigation of Power Signatures for Cavitation and Water Hammer in an Industrial Parallel Pumping System

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    Among the total energy consumption by utilities, pumping systems contribute 30%. It is evident that a tremendous energy saving potential is achievable by improving the energy efficiency and reducing faults in the pumping system. Thus, optimal operation of centrifugal pumps throughout the operating region is desired for improved energy efficiency and extended lifetime of the pumping system. The major harmful operations in centrifugal pumps include cavitation and water hammering. The pump faults are simulated in a real-time experimental setup and the operating point of the pump is estimated correspondingly. In this article, the experimental power quality and vibration measurements of cascade pumps during cavitation and water hammering is recorded for different operating conditions. The results are compared with the normal operating conditions of the pumping system for fault prediction and parameter estimation in a cascade water pumping system. Moreover, the Fast Fourier Transform (FFT) analysis comparison of normal and water hammering (faulty condition) highlights the frequency response of the pumping system. Also, the various power quality issues, i.e., voltage, current, total harmonic distortion, power factor, and active, reactive, and apparent power for a cascade multipump control is discussed in this article. The vibration, FFT, and various power quality measurements serve as input data for the classification of faulty pump operating condition in contrast with the normal operation of pumping system

    An unusual cause of orthopnoea-hashimoto's thyroiditis presenting as bilateral diaphragmatic palsy

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    We report a case of 36 yr old male without any comorbidities, who presented with a history of gradually progressive dyspnoea and orthopnoea for 6 months. Physical examination revealed bradycardia, paradoxical respiration suggestive of bilateral diaphragmatic palsy. Fluoroscopy demonstrated the presence of bilateral diaphragmatic paralysis. Etiological work up showed evidence of autoimmune hypothyroidism due to hashimoto's thyroiditis. Other possibilities were ruled out with appropriate tests. He was started on thyroxine and showed symptomatic improvement

    Phylum XIV. Bacteroidetes phyl. nov.

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