Research Communication in Engineering Science & Technology最新文献

{"title":"Physico-mechanical properties of bio-composites fabricated from polylactic acid and rice husk treated with alkali and ionic liquid","authors":"M. S. Islam, Mohamed Rashid Ahmed-Haras, N. Kao, Rahul K Gupta, S. Bhattacharya, Md Nazrul Islam","doi":"10.22597/RCEST.V2.63","DOIUrl":"https://doi.org/10.22597/RCEST.V2.63","url":null,"abstract":"\u0000 \u0000 \u0000In the present work, chemically treated rice husk (TRH) and untreated rice husk (UTRH) reinforced polylactic acid (PLA) bio-composites were produced using Haake rheomixer and compression moulding processes. Alkali (NaOH) and ionic liquid (IL: 1-ethyl-3-methylimidazolium acetate) treated rice husk samples are TRHN4 and TRHILN4 respectively. Using UTRH, TRHN4 and TRHILN4 the fabricated bio-composites are UTRH-PLA, TRHN4-PLA and TRHILN4-PLA respectively. The tensile strength (TS), tensile modulus (TM), impact strength (IS) and hardness values of TRHN4-PLA and TRHILN4-PLA were found to be much higher than the corresponding values of the UTRH-PLA bio-composites.  The tensile fracture surface morphological features of TRHN4-PLA and TRHILN4-PLA composites, observed by scanning electron microscopy (SEM), revealed less micro voids and fibre agglomerates, which indicates that better filler-matrix interfacial adhesion occurred in the case of chemical treated RH compared to UTRH when blended with PLA. However, composites TRHN4-PLA and TRHILN4-PLA showed lower water uptake capacity compared to UTRH-PLA.  From the FTIR spectra of UTRH, TRHN4 and TRHILN4 together with water absorption behaviour of the composite specimens, it appeared that chemical modifications significantly reduced the hydrophilic nature of RH, resulting in improved fibre-matrix interfacial adhesion. The overall physico-mechanical properties of fabricated bio-composites were found to follow this order: TRHILN4-PLA>TRHN4-PLA>UTRH-PLA. \u0000 \u0000 \u0000","PeriodicalId":326494,"journal":{"name":"Research Communication in Engineering Science & Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132052536","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":"Effect of Drum Pressure on Flow Accelerated Corrosion in Gas Fired Combined Cycle Power Plant: A Case Study and Literature Review","authors":"U. Kumar, Chamely Khatun, Sakinul Islam, N. Kao, F. Rabbi, M. Maniruzzaman, M. Gafur","doi":"10.22597/RCEST.V2.59","DOIUrl":"https://doi.org/10.22597/RCEST.V2.59","url":null,"abstract":"The dissolution of ferrous ions from the protective oxide layer and/or base metal by corrosion with the assistance of turbulent flow is called flow accelerated corrosion (FAC). Flow accelerated corrosion is the most common and continuous corrosion reaction in combined cycle power plants (CCPP). Heat recovery steam generator (HRSG) drum pressure fluctuation and/or turbulent drum water greatly influences the FAC of drum and economizer. This kind of FAC was investigated in the low-pressure drum (LPD) and low-pressure economizer (LPE) of a 210 MW gas-fired combined cycle power plant (Four-unit HRSG & GT) with an air-cooled condenser (ACC). Severe FAC was observed due to the fluctuation of pressure in the LPD with respect to time. As a result, huge amounts of soluble iron (Fe2+) and insoluble (Fe3+) was found in all running HRSG’s LPD water. Due to pressure fluctuations in the LPD, a protective oxide layer (mostly magnetite), as well as the base metal, were corroded from the LPD and LPE even after carefully maintaining recently developed water cycle chemistry in this CCPP. Severe leakage was found in the LPE due to corrosion. The actual reason for the problem was found to be a malfunctioning steam-control valve in the turbine unit’s LP system. This valve was malfunctioning by suddenly opening to 100% and then closing to around 10% continuously. This malfunction creates enormous pressure drops in both the LPD and LPE units. It is understood that water turbulence is the main cause of FAC affecting the LDP and LPE. This assessment is based on chemical laboratory analysis and physical inspection. There was no non-destructive testing (NDT) performed in this study. The severe FAC happened in four days and for this reason, HRSG and steam turbines were shut down. Maintenance work on the control valve and flushing of the LPD and LPE successfully resolved the FAC problem. One week later, LPE leakage was found on the unit-3 HRSG and as reported in this study this was also found to be the result of FAC. From this case study, it is concluded that not only water quality but also water turbulence can create severe FAC problem.","PeriodicalId":326494,"journal":{"name":"Research Communication in Engineering Science & Technology","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132632839","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":"Development of IoT based Heat Exchanger Control Trainer for Undergraduate Process Control Programme","authors":"C. K. Ng, M. F. Zanil","doi":"10.22597/RCEST.V2.57","DOIUrl":"https://doi.org/10.22597/RCEST.V2.57","url":null,"abstract":"Heat exchanger control trainer is a device that helps to demonstrate process control of process variables and simulates real world industrial plant system whereas the implementation of Internet of things (IoT) technology allows wireless communication. This paper describes a work to develop an IoT based heat exchanger control trainer for undergraduate process control programme with the implement Proportional-Integral-Derivative (PID) controller and fuzzy logic controller into the control trainer system together. The work started up with the development of graphical user interface (GUI) for the control trainer followed by the construction and coding of the control trainer prototype. The work has developed a heat exchanger control trainer GUI with PID and fuzzy logic controller. Information was able to be transmitted wirelessly between the GUI and control trainer prototype using Wi-Fi modules. The tested maximum signal strength was -90 dBm in 50 m when connected to indoor Wi-Fi router.  The control trainer was able to achieve simple temperature feedback control of the cold side of the heat exchanger. The user manual included the basic user guide of the developed control trainer user interface. Kp, Ki, Kd of Ziegler-Nichols tuning method obtained in Offline case studies are 90,18, 112.5 whereas 7.2009, 1.1473, and 7.3163 for Cohen-Coon tuning method. The Offline test result shows a better accuracy of control using the fuzzy logic controller with -0.07% of steady-state error. Further improvement could be made to by adding cooling system into the control trainer prototype and apply modern techniques in the GUI control systems.","PeriodicalId":326494,"journal":{"name":"Research Communication in Engineering Science & Technology","volume":"229 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130925486","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":"Estimating Just Suspension Speed for Stirred Reactors Using Power Measurement","authors":"Raja Shazrin Shah Raja Ehsan Shah, B. Sajjadi, A. A. Abdul Raman, T. See, S. Ibrahim, YuanJi Mok","doi":"10.22597/RCEST.V2.58","DOIUrl":"https://doi.org/10.22597/RCEST.V2.58","url":null,"abstract":"A simplified mathematical model was developed to predict the just suspended speed, NJS in a solid-liquid system by analyzing the net impeller power consumption to suspend solid particles. A fully baffled tank with an internal diameter of 400mm equipped with a standard Rushton turbine with a diameter of D=T/3 (133mm) was used in this work. Glass beads were used as the solid phase and distilled water was used as the liquid phase. Solid loadings were varied within the range of 0-27 wt%. Power consumption was measured using the shaft torque method. The predicted NJS values were in a good approximation to the experimental values using the Zwietering’s criterion with a deviation of 2 – 10%. The deviation was lower for higher solid concentrations.","PeriodicalId":326494,"journal":{"name":"Research Communication in Engineering Science & Technology","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115047418","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}