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As throat size and exit area ratio that is tip angle and expansion section mainly influence the nozzle characteristics [5], three factors are considered in the flow field simulation: throat length, tip angle and expansion section length.
Turbulence model is Spalart-Allmaras model which is a single equation model[6]: (1) In the equation, is relevant to eddy viscosity, the expression of viscous damping factor is and the relationship between χ, and molecular viscosity is.
The influence of the throat length on the nozzle outlet parameters The throat size of the nozzle has great influence on the performance of the nozzle, the area and the length of the throat can affect the outlet characteristics.
References [1] Hill P G,Miyagawa K,Denton J D.Fast and Accurate Inclusion of Steam Properties in Two and Three Dimensional Steam Turbine Flow Calculations.in:Procinstn.Mech.Engers.
,Mechanical Engineering Science,2000,214:903-919

Lightweight aggregate and ordinary aggregate has the different physical and mechanical performance characteristics ,and it is easy that lightweight aggregate floating up and segregating of the concrete, low homogeneity, fast slump loss under the pump pressure or during the transportation.
Thus it can be seen, the lightweight aggregate size, the cement paste viscosity, the contrast between lightweight aggregate density and cement paste density, and all is the important factors on the homogeneity of lightweight aggregate concrete.
At the same time, without affecting pump, enhance the viscosity of concrete as far as possible, on the one hand, reduces the water which would be absorbed by lightweight aggregate, on the other hand, the macroviscosity paste can attached to the lightweight aggregate surface, have seal effect to the lightweight aggregate surface hole, may also reduce the pumping pressure function to concrete, so as to achieve the purpose of reducing slump loss. 4.Preparation the large flow pattern pumping lightweight aggregate concrete According to the above analysis, first of all, according to the actual situation, choose the experimental materials ( table 4-1~ table 4-5).
Wet-density (kg/m3) Slump (mm) Divergence （mm） The description of fresh concrete 28d Strength (MPa) inverted slump time (s) 1 1940 220 580 Low encapsulated property, the lightweight aggregate floated up seriously 50.5 14 2 1930 265 630 Middle encapsulated property，the lightweight aggregate floated up mildly 52.8 8 The strength results of each match ratio can meet the design requirements, but in the big slump situation, all lightweight aggregate flow up at different extent, the first group is the most serious (sees Fig. 4-1), it cannot pump.
Through experiments we can see, that after adjustment of 5# match ratio, the concrete viscosity, encapsulated property, paste fluidity, homogeneity all has improved obviously (Fig. 4-2).

The rigidity failure rotational speed is higher the strength failure rotational speed, the connection strength between cutter body and screw bolt affects directly the safety of cutter.
The periodic change in cutting force affects directly machining quality, machining efficiency, and the reliability of high speed end mills [3, 4].
According to the property of the Dirac Function, Fx(t) and Fy(t) are transformed by Fourier Transform [10], we can construct the frequency spectrum functions of dynamic cutting forces dte(t)F(f)P ft2j x ox π− +∞ ∞−∫ ⋅= , dte(t)F(f)P ftj2 y oy π− +∞ ∞−∫ ⋅=
The number of teeth participating in cutting, the rake of cutter, and cutting parameters are important factors affecting the safety and high speed milling performance.
Wan: China Mechanical Engineering, Vol.14 (2003), pp.734

The properties that were analyzed were its crystallite sizes, relative crystallinity, phases, and chemical composition.
Generally, the leaching process is dependent on three or more factors, but in this particular study, only molarity, kinetics, and temperature will be considered [5,6].
These impurities will usually embed themselves in the Ti-O matrix in the form of subsitutional impurities, altering properties such as mechanical strength, band gaps and reactivity [4-6].
For comparison purposes, both the nano-TiO2 and the commercial nano-TiO2 were analyzed for properties such as crystallite size and morphology.
The presence of sulfur, although relatively significant, did not adversely affect the overall mechanical properties of the nano-TiO2 [8].

Workability is an important factor that affects the application and mechanical properties of SCC, in as much SCC in practical use is required to have high fluidity, good filling ability, deformability and moderate segregation resistance [4].
The rheology of concrete can be affected by different factors: characteristics of the cement, mix proportions, time, aggregate properties and type of admixtures, mixing condition and temperature.
Among all these factors, aggregate properties are the most important because the aggregate normally occupies up to 70-80 percent of the total volume of normal concrete [8] while aggregates generally constitute about 60% by volume of SCC [9].
Therefore 10 – 30% unwashed gravel are suitable for fresh properties of SCC.
Neville, Properties of Concrete, fourth ed., Longman, London, England, 2000

It indicates that La2O3 is a suitable additive to MgO-MgAl2O4-ZrO2 brick which not only could stabilize phase transition of dicalcium silicate (C2S) in cement, but also do not impair the high-temperature-properties of spinel.
There are two factors for production and duration of cement clinker crust adhered refractory.
Absence one of these two factors will result in wreck of the crust.
Because high-melting compound La2O3·2ZrO2 has none negative effect on MgO-MgAl2O4 brick’s high temperature properties, furthermore, lanthanum ions act on stabilizing β-C2S phase, MgO-MgAl2O4-ZrO2-La2O3 refractory have excellent high temperature properties and good performance of coating adherence to cement clinker.
Firstly, cement clinker react with refractory and adhere each other to produce cement clinker crust; secondly, clinker crust can existstably by certain substance’s affecting in the refractory.

This work is aimed at studying the physicochemical properties of asphaltic resin paraffins, as well as the mechanism of phase transition from liquid to crystalline.
In this form, the adhesion properties of paraffin are enhanced many times, and its ability to "stick" to hard surfaces is greatly intensified.
Lyubin, Risk assessment of accidents due to natural factors at the Pascuales – Cuenca multiple-use pipeline (Ecuador), Journal of Mining Institute 230 (2018) 190-197 DOI: 10.25515/pmi.2018.2.190
Boitsova, Comparative assessment of structural-mechanical properties of heavy oils of Timano-Pechorskaya province, Journal of Mining Institute, 225, (2017) 320-330 DOI: 10.18454/pmi.2017.3.320
Poletaeva, Review of modern methods of influencing the rheological properties of heavy high-viscosity oils, NefteGazokhimiya, 3 (2018)

The Degradation of Paper-Oil Insulation Change of the properties of oil and paper PCS, during the whole time of life, associated with normal aging and external stresses.
The result is a decrease in the degree of polymerization and weakening of the mechanical properties of paper.
The weakening of the mechanical properties can lead to failure of the cable during short circuits.
The weakening of the mechanical properties can lead to failure of the cable during short circuits.
Calculations show that the degradation of the paper mainly extends towards the deterioration of mechanical properties, electrical properties vary slightly.

Most prominent mode was found out to be mode (b) as it had the highest modal mass participation factor in Y axis bending.
When performing fatigue analysis in nCode results from Glinka et.al [8] and Dowling et.al [10] proved useful to understand and setup the mean stress correction factors in nCode.
From the fatigue results were able to how to notch parameters are able to affect the fatigue life.
It also gave an idea to select material properties for the test specimen as the test specimens were to selected based on their fatigue life.
This may be due to difference in input material properties of the beam in FEA and in test. 3.5 Application of Study To correlate the effect of these results, it was tested on a radiator frame.

Taking all above factors, specific surface area of 550m2/kg on clinker is chosen in this investigation.
The effect of slag on the mechanical properties of LCC can be concluded into three aspects.
Fig. 4 Particle size distribution of fly ash (FA1 FA2) by laser particle analyzer Fig. 5 Particle size distribution of slag (S1 S2 S3) by laser particle analyzer Conclusions Based on the above results, LCC with lower power consumption, better environmental protection and higher mechanical properties can be successfully developed.
Hibbert, Selected engineering properties of concrete incorporating slag and metakaolin, Construction and Building Materials. 19(2005) 460-472
[10] Huiwen Wan, Zhonghe Shui, and Zongshou Lin, Analysis of geometric characteristics of GGBS particles and their influences on cement properties, Cement and Concrete Research. 34(2004) 133-137