C. Borzea, V. Petrescu, Iulian Vlăducă, M. Roman, G. Badea
{"title":"POTENTIAL OF TWIN-SCREW COMPRESSOR AS VIBRATION SOURCE FOR ENERGY HARVESTING APPLICATIONS","authors":"C. Borzea, V. Petrescu, Iulian Vlăducă, M. Roman, G. Badea","doi":"10.36801/apme.2021.1.12","DOIUrl":"https://doi.org/10.36801/apme.2021.1.12","url":null,"abstract":"The paper presents the vibrational behaviour of a twin-screw compressor at various functioning regimes. The speed is varied by means of a 250 kW electric driving motor, via a frequency converter. The compressor can supply pressurized air up to ~16 bar into a buffer tank. The air is used for testing various equipment on test bench, such as expanders, pneumatic starters for gas turbine engines, or other compressors and blowers used for compressing air starting from a pressure higher than the atmospheric pressure. Like all other industrial equipment, compressors experience inherent vibrations in operation. The pulsatory effects of the air within the compressor also give birth to harmonics. The study herein involves gathering vibration data and represent it as vibration spectra. Raw vibration signals, employed for assessing the condition of the machinery, may not always be clear in the frequency spectrum for vibration analysis, thus being required to apply Fast Fourier Transform for converting the time waveform into frequency spectrum. The study herein pursues a future application of energy harvesting from vibrations, and outlines that the spectral analysis of the compressor is convenient for piezoelectric cantilever harvesters in terms of vibration frequency and amplitude.","PeriodicalId":185216,"journal":{"name":"ACTUALITĂŢI ŞI PERSPECTIVE ÎN DOMENIUL MAŞINILOR ELECTRICE (ELECTRIC MACHINES, MATERIALS AND DRIVES - PRESENT AND TRENDS)","volume":"251 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117289297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"ON SOME COMPARISON BETWEEN ACCELERATED AGING OF MINERAL OIL UNDER HIGH ELECTRIC FIELD AND HIGH TEMPERATURE","authors":"A. Manea, L. Dumitran, Teodora Gorjanu, C. Borzea","doi":"10.36801/apme.2021.1.6","DOIUrl":"https://doi.org/10.36801/apme.2021.1.6","url":null,"abstract":"During the operation of electric power transformers,their insulation often made from paper and mineral oil is subjected to thermal, mechanical, and electrical stresses. Therefore, the lifetime of power transformers can be assimilated with their insulation system lifetime. The aim of this paper is to explore and present main degradation aspects for mineral oil, subjected to the action of high electrical field and partial discharge and exposure to thermal stress exclusively, analyzing and pointing out changes in the dielectric properties. Thus, the obtained results indicate that both the thermal and, especially, the electrical stresses produce important variations of the values of the real and imaginary part of the complex relative permittivity, the electrical conductivity, and the loss factor which indicates a severe oil degradation.","PeriodicalId":185216,"journal":{"name":"ACTUALITĂŢI ŞI PERSPECTIVE ÎN DOMENIUL MAŞINILOR ELECTRICE (ELECTRIC MACHINES, MATERIALS AND DRIVES - PRESENT AND TRENDS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129768811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Smeu, C. Ghita, A. Chirilă, D. Deaconu, V. Năvrăpescu
{"title":"COMPOSITION OF A DRINKING WATER PUMP GROUP PREPARED FOR IOT TECHNOLOGY","authors":"G. Smeu, C. Ghita, A. Chirilă, D. Deaconu, V. Năvrăpescu","doi":"10.36801/apme.2021.1.14","DOIUrl":"https://doi.org/10.36801/apme.2021.1.14","url":null,"abstract":"Technological developments in the field of sensors, transducers and data transmission lead to the development of industrial automation. In the field of drinking water distribution networks, this evolution brings a significant value contribution, in the form of savings at the time of implementation, as well as savings in operation. The paper seeks to highlight a method of sizing a pump set prepared for IoT (Internet of Things) technology. In essence, this form of pump group eliminates the need to implement industrial automation for group management and operation. The whole working logic is based on artificial intelligence and the statistics of the data accumulated by the network interconnected by intelligent sensors.","PeriodicalId":185216,"journal":{"name":"ACTUALITĂŢI ŞI PERSPECTIVE ÎN DOMENIUL MAŞINILOR ELECTRICE (ELECTRIC MACHINES, MATERIALS AND DRIVES - PRESENT AND TRENDS)","volume":"192 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123482544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"PROGRAM AND SUMMARIES OF THE PAPERS PRESENTED","authors":"","doi":"10.36801/apme.2014.1","DOIUrl":"https://doi.org/10.36801/apme.2014.1","url":null,"abstract":"","PeriodicalId":185216,"journal":{"name":"ACTUALITĂŢI ŞI PERSPECTIVE ÎN DOMENIUL MAŞINILOR ELECTRICE (ELECTRIC MACHINES, MATERIALS AND DRIVES - PRESENT AND TRENDS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129981995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}