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Effect of Slit Inclusions in Drag Reduction of Flow over Cylinders Rohit Bhattacharya, Abouzar Moshfegh and Ahmad Jabbarzadeh* School of Aerospace, Mechanical and Mechatronics Engineering, The University of Sydney, NSW 2006, Australia * Corresponding author: ahmad.jabbarzadeh@sydney.edu.au Keywords: CFD, Lattice-Boltzmann, Drag reduction, Flow over slit cylinder Abstract.
The effect of slit size on drag reduction is studied and discussed in detail in the paper.
That work demonstrated that for a slit/diameter ratio of 0.16 approximately 13% reduction in the drag coefficient can be achieved.
Literature Cd Cd obtained by CFD Cd obtained by LBM 5.67 (Dinesh) [7] (Poiseuille Flow) 5.31 5.52 3.43 (Tuann et al) [8] (Free Flow) 5.31 5.52 The reported data indicate that the values of the drag coefficients obtained from LBM and CFD simulation are very close to prior works results.
Table 3: Drag coefficient and % reduction in comparison to slit free cylinder, calculated from CFD and LBM for various slit ratio and compared.

In the real fault prediction, the test data is redundant and incomplete, and Rough Set Theory can reduce the redundant information and extract the useful information.
The classical attribution reduction algorithm given by [4].
In which, the attribution reduction algorithm are as bellows: Input: decision table S=(U,A,V,f); Output: all the reduction REDC(D) of decision table.
The grey prediction model steps are as bellows: Step 1: x(0)(t) is accumulated generating to get ; Step 2: Calculate data matrix B and the data row Y; Step 3: Calculate a and b by ; Step 4: Establish model ; Step 5: Calculate prediction accumulated value ; Step 6: Calculate the prediction value ； Step 7: Calculate ,。
Firstly, the data is discretized because Rough Set Theory only can process the discretized data.

Date accepted: 06 July 2013] Keywords: Fe2O3 reduction; Metallurgical coke; End-of-life tyres; Extent of reduction; Carburisation.
An IR gas analyser (Advance Optima model ABB^® AO2020) attached to this system was used to monitor CO and CO2 gases produced by the reactions and the results were recorded in a data-logging computer.
Figure 11 Change in extent of reduction with time at 1500 °C From Figure 11, RT and the blends are able to reduce the iron oxide rapidly, attaining at least 80% reduction in less than 600 seconds; within this time the reduction by coke is about 67%.
In particular, H2 apart from being a faster reducing agent than both CO and solid carbon enhances the rate of reduction of iron oxides by CO [8,9] when it is added to a reduction system containing the latter.
Rajakumar, Gaseous reduction of wustite with H2, CO and H2-CO mixtures, Trans.

The results demonstrate that switching the operation of an office building HVAC system from CV to VPF will significantly enhance energy savings and CO2 reduction.
The office building selected for this energy-saving and CO2 reduction study is located in central Taiwan; it is rectangular with a foot-print of 33.5 m (length) by 33.2 m (width).
Each set of data is the average value of three successive monitoring data.
Significant CO2 reduction is observed in the VPF system as compared with the CV system.
The accumulated power consumption increases from 21,757 to 468,299 kWh (data not shown), and the reduction of accumulated CO2 emission increases from 0 to 44,186 kg/year (The emission factor for electricity = 0.623 kg CO2/kwh) for the VPF chilled water system.

The so-called shear strength reduction method is for an ideal elastic-plastic finite element system and is such a process, in which the shear strength parameters of the sliding mass are gradually decreased by a varying reduction coefficient, until the system achieves an unstable state and the finite element static analysis is not convergence, and the strength reduction factor at the situation is the safety factor we want [4, 5].
Where, F is reduction coefficient or safety factor.
Through the test a lot of data were obtained.
The foundation parameters are from geological exploration data, and they are listed in Fig.3.
The calculation model for strength reduction method is shown in Fig.3 (The grade of side slope was determined as 1:1.5.

AlN whiskers have been successfully synthesized by carbothermal reduction.
Others mechanisms have been proposed to describe the growth AlN whiskers by carbothermal reduction [14].
From the above thermodynamic calculations using published data [16], it can be concluded that in the presence of Ca-aluminates liquid phase, the reactions (5) and (6) can proceed consecutively at reaction temperatures, which are significantly lower than those that would be required in absence of CaCO3.
Steps on growing and on the top of an AlN crystals Conclusions The data presented and discussed along the present paper enable to draw the following conclusions: (1) The carbothermal reduction-nitridation of Al2O3-C-N2 system in the presence of CaCO3 occurs through a series of intermediate Ca-aluminates to form AlN
Schultze-Rhonhof: Thermochemical data of pure substances, second edition (Weinheim, Germany VCH Verlagsgesellschaft mbH, D-6940, Weinheim 1993)

Properties of Carbide-Metal Cermets Prepared from Composite Powders by Direct Reduction and Carburization Process L.
The carbothermal condition was greatly improved by the direct reduction and carburization process.
Ultrafine TaC-Co powder is prepared by spray-drying and reduction/carburization process in a non-oxidizing atmosphere [10].
The test data of Rockwell hardness and transverse rupture strength (TRS) are shown in Table 1.
Conclusions (1) The present work demonstrates a powerful and simple process - direct reduction and carburization process for manufacturing carbide-metal composite powders.

The reduction product of PNP was identified through HPLC and UV-vis.
The effect of cosubstrate concentration and PNP loading rate on PNP reduction and reduction product formation was also included.
Results and discussion Effects of different external cosubstrates on PNP reduction and PAP formation External cosubstrates play an important role in PNP reduction process.
Furthermore, the peaks with retention time of 6 min in HPLC of effluent were identified as PAP (data not shown), further demonstrating that PAP was the dominant product of PNP reduction in UASB.
However, no further degradation of PAP was observed in UASB, even when HRT was extended to 24 h or longer (data not shown), indicating that PAP could not be degraded under anaerobic condition.

And then using the selected data gear is to be designed based on compressive and the bending strength using general procedure for the design of gears.
, two stage reduction spur gears are used as the reduction cannot be achieved by single reduction using spurs.
Therefore the module chosen is correct. 3 Results and discussions The gear is modelled using the software with data specified in the previous chapter.
Fig. 3.3 Gear with elliptical and circular holes 3.3 Mass Reduction of Gear The other objective of the project is mass reduction.
[9] Faculty of mechanical engineering, PSG College of Technology, Coimbatore, “Design data – Data book for engineers”, M/s.

According to Ayegba et al [2], the friction reduction is almost depending on the form of pipes.
It was shown that the friction reduction is lower in curved pipe flows compared to straight pipe.
The experimental data was fitted by Casson model presented by the following equation [21, 22]: τ=τ0+2γη∞τ0γ.
Abubakar , Drag reduction with polymer mixtures in pipes of different diameters.
Sasmito , Pressure loss and friction factor in non-Newtonian mine paste backfill: modelling, loop test and mine field data, Powder technology. 344 (2019) 443-453