9 research outputs found
Noise Level Investigation and Control of Household Electric Power Generator
Electric power generator is an essential household facility particularly in developing countries. It exists in various capacities and makes in shops, offices, workshops and factories. The attendant environmental risks of this source of power supply are major challenges to users both at household and industrial level. Efforts through research and development are still on-going to mitigate the prevailing health hazards. This study investigates noise level of typical portable generator (2 kW/220 V) and the sound absorbance capacity of an acoustic enclosure developed from a multilayer panel made of locally sourced galvanized metal sheet (0.90 mm), Polyurethane acoustic foam (7.50 mm), Particle board (35.0 mm) and plywood (10.0 mm). The noise produced by the generator when on load and no load were considered for cases of it being placed inside and outside the enclosure and compared with acceptable OSHA safe thresholds noise level for the school environment where the study was carried out. The result shows a significant reduction of noise produced indicating a shift from very laud threshold (average of 86.23 dB (A)) for no load and no enclosure to moderately low region (average of 69.34 dB (A)) for the case of no load using enclosure. Likewise considering loaded scenario similar trend was recoded with average acoustic capacity of the enclosure of 23.20 dB (A). The effect of the enclosure is positive and the potential benefits of improved noise absorption panels to enhance better performance of the developed enclosure for office and household generators was established. Keywords: Electric Generator, Enclosure Panel, Noise control, Load, Household
Effect of particle size and weight percentage variation on the mechanical properties of periwinkle shell reinforced polymer (epoxy resin) matrix composite
Polymers are very interesting and useful materials that have many applications in
various areas of engineering. Composites formed with these materials are known to
exhibit outstanding mechanical, electrical, and thermal properties. In this work, a
polymer, epoxy resin, was reinforced with a biodegradable material, periwinkle shell
(PWS) particles, using the hand lay-up method. The PWS was pulverized using a ball
mill and three sieve sizes of the PWS (75, 150, and 300 μm) were sieved out. Various
samples of the composite were produced by reinforcing the epoxy resin matrix with 10,
20, 30, 40, and 50 wt% of each of the PWS particle sieve sizes. The samples so formed
were subjected to the following mechanical tests: hardness, tensile, compressive, and
impact tests. It was found out that the samples of composites showed higher values of
the parameters tested for than ordinary epoxy resin showed. In the samples of composites,
it was found that the samples with a higher weight percentage of the PWS reinforcement
recorded higher values of those mechanical properties tested for. The higher the weight
percentage of the PWS in the composite, the greater the value of the mechanical property
tested for
MODELING AND OPTIMIZATION OF SURFACE ROUGHNESS IN END MILLING OF ALUMINIUM USING LEAST SQUARE APPROXIMATION METHOD AND RESPONSE SURFACE METHODOLOGY
In end milling, accurate setting of process parameters is extremely important to
obtained enhanced surface roughness (SR). Due to a recent innovation in
mechanization made it possible to produce high quality manufacturing products. The
perceptions of quality in mechanical products are their physical look that is the
surface roughness (SR). The aim of this research work is to develop mathematical
expression (M.E) and mathematical model using least square approximation method
and Response Surface Methodology (RMS) to predict the SR for end milling of Al 6061
alloy. The process parameters that were selected as predictors for the SR are Spindle
speed (V), axial depth of cut (a), feed rate (f) and radial depth of cut (d). 30 samples of
Al 6061 alloy were carried out using SIEG 3/10/0010 CNC machines and each of the
experimental result was measured using Mitutoyo surface roughness tester and Presso-
firm. The minimum SR of 0.5 μm were obtained at a spindle speed of 2034.608 rpm,
feed rate of 100 mm/min, axial depth of cut of 20 mm, and radial depth of cut 1.5 mm.
Analysis of variances shows that the most influential parameters was feed rate. Afte
Experimental Analysis of the Wear Properties of Carburized HSS (ASTM A600) Cutting Tool
Prediction and control of undesirable deterioration of cutting
tools are the most essential challenges emanating in the design
of tool which has to be checked. As a result of an increase in
wear rate of HSS cutting tools, so has the need for wear
resistant. The result has been a progression of carburizing the
tools for better performance. Based on the theoretical analysis
and study of tool wear and parameters that mitigates against
wear resistance of cutting tools, this research work presents an
experimental investigation and analysis of the wear properties
of carburized HSS cutting tools. Twelve Samples under
consideration were carburized HSS (ASTM A600) tools
(0.65% C) treated at 800,850,900 and 950oC with holding
time of 60, 90 and 120 minutes respectively. The wear
properties of weight loss, wear volume, wear resistance and
wear rate were carried out using Rotopol –V, impact tester,
polisher, grinder and weight scale. It was found from the
experiment carried out that cutting tool(sample 5) carburized
at holding temperature and time of 800 oC and 90 minutes has
the lowest cutting weight loss, volume and wear rate of 0.002
g, 0.00026 cm3
and 5.476 X10-10 cm2
with maximum wear
resistance of 1.83X109
. This showed that sample 5 has the
best wear properties which undermined the general believe
that the sample with highest holding temperature and time
should have the highest wear properties. This experiment has
further established carburization as one of the heat treatment
methods that involved carbon penetration to the depth that
improved wear rate and resistance of a material
Typical meteorological year data analysis for optimal usage of energy systems at six selected locations in Nigeria
Inthisstudy,thetypicalmeteorologicalyear(TMY)dataforsixlocationsrepresentingthesixgeopoliticalzonesinNigeriaweregeneratedandanalyzedusingtheSandiamethod.Theanalysisshowsthatseasonalvariationsexistinalltheselectedlocationsindicatingtwodistinctseasons:thedryandwetseasonswithvaryinglengthsfromnorthtosouthofthecountry.Duetoitshighglobalradiationlevels(21–25MJ/m2/d),theNorthisadesirablelocationforsolar-thermalsystems.Inaddition,thehighmonthlymeantemperaturevariations(∼18◦C),lowrelativehumidity(RHM)(15%)andconstantwindspeeds(4m/s)experiencedinthefirst3monthsoftheyearaidtheinstallationofwindenergysystemsandtheapplicationofevaporativecoolingtechniquesthatreucethethermalloadandenergyconsumptionofbuildings.Ontheotherside,thehighRHM(80%)andmediocreradiationvaluesderivedalmostthroughouttheyearintheSouthwest,SoutheastandSouth–southregionsdiscouragestheextensiveapplicationofevaporativecoolingandsolarenergy-basedsystemsinsuchlocations,butthemoderatewindspeeds(2.9m/s)andmonthlymeantemperaturevariationsassociatedwiththeseregionsbetweenthefirst3monthsoftheyearallowfortheapplicationofnaturalventlationandsomepassivecoolingsystemssoastoreducethethermalloadofbuildingsintheregions.Theinformationpresentedinthisworkcanserveasaguidefordesignandselectionofenergysystemsandapplicationofenergy-relatedprojectsinNigeria
MODELING AND OPTIMIZATION OF SURFACE ROUGHNESS IN END MILLING OF ALUMINIUM USING LEAST SQUARE APPROXIMATION METHOD AND RESPONSE SURFACE METHODOLOGY
In end milling, accurate setting of process parameters is extremely important to obtained enhanced surface roughness (SR). Due to a recent innovation in mechanization made it possible to produce high quality manufacturing products. The
perceptions of quality in mechanical products are their physical look that is the surface roughness (SR). The aim of this research work is to develop mathematical expression (M.E) and mathematical model using least square approximation method and Response Surface Methodology (RMS) to predict the SR for end milling of Al 6061
alloy. The process parameters that were selected as predictors for the SR are Spindle speed (V), axial depth of cut (a), feed rate (f) and radial depth of cut (d). 30 samples of Al 6061 alloy were carried out using SIEG 3/10/0010 CNC machines and each of the experimental result was measured using Mitutoyo surface roughness tester and Presso-firm. The minimum SR of 0.5 μm were obtained at a spindle speed of 2034.608 rpm, feed rate of 100 mm/min, axial depth of cut of 20 mm, and radial depth of cut 1.5 mm.
Analysis of variances shows that the most influential parameters was feed rate. After the predicted SR has been obtained by using the two methods, average percentage
deviation was calculated, the result obtained using least square approximation method (that is the mathematical expression) show the accuracy of 99% and Response
Surface Methodology (RSM) mathematical model shows accuracy of 99.6% which is viable and appropriate in prediction of SR. When either of these models are applied this will enhance the rate of production
Data showing the effects of temperature and time variances on nano-additives treatment of mild steel during machining
The effects of temperature and time variances on nano-additives treatment of mild steel during machining was presented in this study. Mild steel of 150 kg mass containing 0.56% carbon was charged into the furnace at melting and pouring temperature of 1539 and 1545 °C respectively. Also charged into the furnace with the mild steel were 0.05% max phosphorous and a bit of sulphur. Thereafter, the sample was cooled and annealed at a temperature of 900 °C for 9 h and then cooled to 300 °C of hardening, normalizing and tempering respectively. The treated samples were then soaked with pulverized in palm kernel shell and barium carbonate (20%) energizer at respective temperatures (800, 850, 900 and 950 °C) and time variances (60, 90 and 120 min) in a muffle furnace. The developed tool was tested on a lathe machine to evaluate its performance. The surface and core hardness, wear resistance and toughness were carried out using the hardness tester, Rotopol–V and impact tester respectively. This is essential for predicting the useful life of the tool in service. Keywords: Nano-additive, Medium carbon steel, Case-hardening, Machinin
Data showing the effects of temperature and time variances on nano-additives treatment of mild steel during machining
The effects of temperature and time variances on nano-additives treatment of mild steel during machining was presented in this study. Mild steel of 150 kg mass containing 0.56% carbon was charged into the furnace at melting and pouring temperature of 1539 and 1545 °C respectively. Also charged into the furnace with the mild steel were 0.05% max phosphorous and a bit of sulphur. Thereafter, the sample was cooled and annealed at a temperature of 900 °C for 9 h and then cooled to 300 °C of hardening, normalizing and tempering respectively. The treated samples were then soaked with pulverized in palm kernel shell and barium carbonate (20%) energizer at respective temperatures (800, 850, 900 and 950 °C) and time variances (60, 90 and 120 min) in a muffle furnace. The developed tool was tested on a lathe machine to evaluate its performance. The surface and core hardness, wear resistance and toughness were carried out using the hardness tester, Rotopol–V and impact tester respectively. This is essential for predicting the useful life of the tool in service. Keywords: Nano-additive, Medium carbon steel, Case-hardening, Machinin