SOME ASPECTS OF PRACTICAL BALANCING RIGID ROTORS IN OWN SUPPORTS

The balancing of rotors of fans, pumps, smoke exhausters, blowers (with a capacity of 50...500 kW, with a rotational speed of 950...3000 rpm) in their own supports is carried out most often at industrial enterprises. The effectiveness of this operation is ensured by the implementation of a number of rules, confirmed by practical experience. Some stages of balancing of rotors are considered in the work. A preliminary examination of the mechanism provides an accurate diagnosis and an informed decision for balancing. Correct determination of the angle of installation of the test cargo at various places of installation of the vibration and photo sensor allows reducing the level of vibration and additional loads on the elements of the mechanism during the test run. Controlling the values of the dynamic coefficient of influence during the balancing process allows you to control the change in the stiffness of the base, loosening of threaded connections, which are often the cause of unsuccessful balancing. The above provisions are confirmed by the results of research and practical application.

Characterisation of SiPM Photon Emission in the Dark

In this paper, we report on the photon emission of Silicon Photomultipliers (SiPMs) from avalanche pulses generated in dark conditions, with the main objective of better understanding the associated systematics for next-generation, large area, SiPM-based physics experiments. A new apparatus for spectral and imaging analysis was developed at TRIUMF and used to measure the light emitted by the two SiPMs considered as photo-sensor candidates for the nEXO neutrinoless double-beta decay experiment: one Fondazione Bruno Kessler (FBK) VUV-HD Low Field (LF) Low After Pulse (Low AP) (VUV-HD3) SiPM and one Hamamatsu Photonics K.K. (HPK) VUV4 Multi-Pixel Photon Counter (MPPC). Spectral measurements of their light emissions were taken with varying over-voltage in the wavelength range of 450–1020 nm. For the FBK VUV-HD3, at an over-voltage of 12.1±1.0 V, we measured a secondary photon yield (number of photons (γ) emitted per charge carrier (e−)) of (4.04±0.02)×10−6γ/e−. The emission spectrum of the FBK VUV-HD3 contains an interference pattern consistent with thin-film interference. Additionally, emission microscopy images (EMMIs) of the FBK VUV-HD3 show a small number of highly localized regions with increased light intensity (hotspots) randomly distributed over the SiPM surface area. For the HPK VUV4 MPPC, at an over-voltage of 10.7±1.0 V, we measured a secondary photon yield of (8.71±0.04)×10−6γ/e−. In contrast to the FBK VUV-HD3, the emission spectra of the HPK VUV4 did not show an interference pattern—likely due to a thinner surface coating. The EMMIs of the HPK VUV4 also revealed a larger number of hotspots compared to the FBK VUV-HD3, especially in one of the corners of the device. The photon yield reported in this paper may be limited if compared with the one reported in previous studies due to the measurement wavelength range, which is only up to 1020 nm.

An Electromagnetic Vibration Energy Harvester with a Tunable Mass Moment of Inertia

This paper presents a vibration-based electromagnetic energy harvester whose resonance frequency can be adjusted to match that of the excitation. Frequency adjustment is attained by controlling a rotatable arm, with tuning masses, at the tip of a cantilever-type energy harvester, thereby changing the effective mass moment of inertia of the system. The rotatable arm is mounted on a servomotor that is autonomously controlled through a microcontroller and a photo sensor to keep the device at resonance for maximum power generation. A mathematical model is developed to predict the system response for different design parameters and to estimate the generated power. The system is investigated analytically by a distributed-parameter model to study the natural frequency variation and dynamic response. The analytical model is verified experimentally where the frequency is tuned from 8 to 10.25 Hz. A parametric study is performed to study the effect of each parameter on the system behavior.

Design and Development of a Solar-Powered Pump System with Liquid Level Sensor and Controller Using Internet of Things Iot Technology

Renewable energy in our world today has greatly helped the ecosystem by reducing the amount of carbon content in the atmosphere. Recent studies have shown that the dependence on the National grid and fossil fuels for generating power for pumps is becoming alarming and as such, an alternative source for energy generation to power the pump system necessitated this research. The research relies on solar-generated power for driving pumps as opposed to fossil fuels. A submersible centrifugal pump was used because of its wide usage in various industries such as Oil and Energy, Pharmaceutical, Breweries, Production industries, Water corporations, Domestic and Commercial buildings, etc. We designed and constructed an automatic solar-powered pump system, integrated, and programmed the sensors using Arduino microcontroller and C++ programming language, respectively. We analyzed the telemetry data from the sensors and predicted the illuminance of light on the solar panel and sent the information via a web server using a GSM module. The solar-based pumping system consists of a submersible centrifugal pump, solar panel, solar charge controller, battery, remote controller, GSM module, photo sensor and a liquid level sensor. The photo sensor returns values ranging from 0 to 1023. The higher values: 700 – 1023 indicate that the sensor is in darker surroundings. The lower values: 0 - 650 indicate lighter surroundings when there is sufficient light on the sensor or its surroundings on the web server which display the plotted values in real-time. The system has been found to be viable and economical in the long run compared to the conventional system which uses fossil fuels. The solar energy received from the sun is converted to electrical energy by the solar panel. A proportion of the energy is used during the day while some is stored in the battery to be used at night or when the weather is cloudy. The controller regulates the liquid level in storage with the aid of liquid level sensor and affords the user the opportunity to control the system remotely. This system can be used for small and remote applications.