http://suspace.su.edu.bd/handle/123456789/85 Sat, 18 Apr 2026 12:37:39 GMT 2026-04-18T12:37:39Z http://suspace.su.edu.bd/handle/123456789/573 Scenario of Safety Issues Prevailing Accident in Rural Engineering Workshop in Bangladesh Rahman, Mahbubur; Hossain, Md. Arafat; Hossain, Md. Mostofa Safety is the condition being protected against any hazardous situation and any other type of failure, error and accidents. As a developing country our technology is growing day by day. But the man who works to develop this technology and works in different industries, factories and rural engineering workshops is deprived of their required safety. The safety issues provided for the workers are not properly maintained in Bangladesh. Almost no safety is providedfor the workers in rural engineering workshop in Bangladesh andfor that they are suffering from various problems such as financial, physical, social, spiritual, occupational etc. Many accidents have already been taken place due to not providing enough safety to the workers. Therefore, safety must be provided minimizing accident hazards and risks. The workshops safety situation in Bangladesh is very severe by international standard. An overview ofthe prevailing accident problem characteristics and some working safety priorities that should be addressed with due urgency are briefly discussed in the paper. In this paper an attempt has been made to highlight the workers safety issues in rural engineering workshops in Bangladesh. Sun, 10 Dec 2017 00:00:00 GMT http://suspace.su.edu.bd/handle/123456789/573 2017-12-10T00:00:00Z http://suspace.su.edu.bd/handle/123456789/572 Energy Storage in an Impure Paraffin Wax Embedded in the Finned-Annulus of Two Horizontal Tubes: Part-Il Tabassum, Tonny; Hasan, Mainul; Begum, Latifa This Part-Il of the manuscript reports on the unsteady two-dimensional numerical investigations of melting of a paraffin wax (phase change material, PCM) which melts over a temperature range of 8.70C. The PCM is placed inside a circular concentric horizontal-finned annulus for the storage of thermal energy. The inner tube is fitted with three longitudinalfins which are placed strategically near the bottom part of the annulus to accelerate the melting process. The non-dimensional conservation equations for mass, momentum, and energy are solved employing a staggered control-volume based finite difference method using the previously verified in-house CFL) code. Under identical geometrical configuration and operating conditions, the melting characteristics of the finned annulus are compared with the annulus without fins presented in Ref [l]. The numerical results show that the average Nusselt number over the inner tube surface, the total melt fraction, the total stored energy all increased at every time instant in the internally finned annulus compared to the annulus without fins. This is due to the fact that in the finned annulus, the fins at the lower part of the annulus promotes buoyancy-driven convection as opposed to the slow conduction melting that prevails at the bottom part of the plain annulus. Fins with two different heights have been considered. It is found that by extending the height of the fin to 50% of the annular gap about 33.05 0 0 more energy could be stored compared to the bare annulus at the melting time of82.37 min for the identical operating conditions. The effects offins with different heights on the temperature distribution are found to be different. The present study can provide some useful guidelines for achieving a better energy storage system and also can aid in the design/optimization ofthe shell-and-tube LHTES devices. Sun, 10 Dec 2017 00:00:00 GMT http://suspace.su.edu.bd/handle/123456789/572 2017-12-10T00:00:00Z http://suspace.su.edu.bd/handle/123456789/127 A Review on Renovation of Gas Turbine to Improve Efficiency by using compressor water wash Rahman, Mahbubur; Hossain, Md. Mostofa Hossain The abitity to predict the behavior of a turbine engine and optimize its performance is important in economic, thermal and condition obseruation studies. Fouling is one of the maior sources oJ compressor deterioration. So, the paper presents an analysis of the ffictiveness of online and olfline compressor washing using numerous puriQ grade waters and industrial washing detergents. Fri* go, turbine ixial compressor blades fouling dirt of blade.surface **as obtctined at numerous fielisites. To see the composition and consistency of typical blade surlace fouling materials the dirt was analyzed. An exemplaty dirt formulq and blade coating procedtrre "was finnttlated so comparative tests can be performed using numerous cleanup fluids' To see the ,opibitity or benefits i7 ony liquid a spray iozzle upstream of _the btade test section was used for ctlaning btades withfive totaily dffirent cleaning liquids. In dffirent residue experiments the imp"act of high-purity water yersus regular water on fouling dirt was coniointly studied' Results showed that an important means oJ-cleaning compressor blade is spraying cleaning.fluid into a Jlowing oir stream. Every of the Jlitds w,ere ready to clean the test blade at each lov' and high iir velocities and at toialiy different blecle incident angles. The Results shou'ed that "Jn pr"rro, blade washing is primariiy a mechanical work and does not rely on the kind of .fluid ,r"i yo, washing. The reiulti also showed that almost all of the cleaning happens shortlv when the cieaning Tuia x introduced into the flow stream. As the cleaning fluid is evaporated, the dirt aloof ./ioi the blades might redeposit in dffirent areos' To optimize the performance o.f turbine engines, it is therifore suggestetl that operators ought to p Thu, 15 Jun 2017 00:00:00 GMT http://suspace.su.edu.bd/handle/123456789/127 2017-06-15T00:00:00Z http://suspace.su.edu.bd/handle/123456789/125 Modified Roof-Top Garden as a Tuned Mass Damper for Vibration Control of Building Structure Under Earthquake Excitation Rahman, Mohamrnad Sabbir Rahman; Sarraz, Atik; Islam, Mohammad Saiful; Hasnat, Abul Tuned Mass Damper(TMD) is very popular to mitigate the vibration of the structure under any Qpe of random loadings like as Wind or Earthquakes. This researchwork mainly.focuses on to modify the roof- top garden as a passive vibration controlling devices (RTGD) using the same principle of TMD.One of the important features of TMD is using huge mass to create the inertial Jbrce against earthquake forces. This passive energy dissipation system is not neededany additional mass becatrse the mass o.f roof garden used as a TMD mass which is come from the mass of soil and plants. The roof and roof-top garden have been isolatecl by springs which have been given the spring fttrce and also installed q yiscous damper to provide the damping force against earthqtrakeforces. Partially saturated soil condition of roof top garden h.as been taken to qvoid the detttning elJbct. The obtained structural response under different earthquakes proved that this system is one of most capable to mitigate the Earthquake vibration ori,rn bi easily used in pract ically.for building thestructures. Thu, 15 Jun 2017 00:00:00 GMT http://suspace.su.edu.bd/handle/123456789/125 2017-06-15T00:00:00Z