Jet test

Impingement and erosion-corrosion forms of attack will usually be intensified by the presence of solid particles in the fluid. Variations of the jet test have been proposed to take this effect into account. ... 

Gulabivala, K., Setchell, D. J. Davies, E. H. (1987). An application of the jet test method for the evaluation of disintegration of dental luting cements in marginal gaps analogous to those of crowns and bridges. Clinical Materials,... 

The laboratory impinging jet test for evaluating the acid erosion of dental cements is described in Chapter 10. Using this method with lactic acid-lactate solutions, Wilson et al. (1986b) found, for one cement, that the erosion rate was virtually zero at pH = 5 0, 0-38 % at pH = 4-0 and 5 7 % at pH = 2-7. For a range of cements Wilson et al. (1986a) found erosion rates varying from 3 0 to 5-7 % in lactic add solutions of pH = 2-1. The... 

Billington, R. W., Williams, J. A. Pearson, G. J. (1992). In vitro erosion of 20 commercial glass ionomer cements measured using the lactic acid jet test. 

Figure 2. Time dependence of catalyst attrition in a submerged jet test (D, = 0.05 m, uor = 100 ms-1, dor = 2 mm, HA-HPV is a fresh catalyst whereas FCC is a spent cracking catalyst from a commercial unit. (From Werther and Xi, 1993.)...

Both devices described above were developed in order to test the friability of fluid-cracking catalysts. Nowadays the application of these or similar tests is a common procedure in the development of fluidized bed catalysts. Contractor et al. (1989), for example, used a submerged-jet test to compare the attrition resistance of newly developed VPO catalysts. In fact, such tests can be applied to any type of fluidized bed processes. Sometimes they have to be slightly modified to adapt them to the process under consideration. The drilled plate may, for example, be substituted by... 

Control was implemented by the oscillation of fuel in the axial jet. Tests with a wide range of flow conditions showed that the oscillation of more than around 6% of the total fuel flow did not result in improved attenuation of the oscillations, except for small overall equivalence ratios around 0.65 for which the larger flow rates of fuel in the axial jet led to an increase in amplitude of oscillations and the oscillation of that flow resulted in an increase in attenuation. 

A2) Air Jet Test. The purpose of this test is to measure the arming time of vane-operated bomb fuzes and also to check the suitability of bearings. The test consists of applying a jet of air to the mounted fuze vane (p IIB-35 of Ref 39)... 

Protective films on metals also can be destroyed and corrosion accelerated by the impingement of a high-velocity stream of sea water onto the metallic surface. The inlet ends of condenser tubes, are frequently attacked (Figure 3,a). Jet tests have been devised for ranking the susceptibility of metals to such impingement attack. A corrosion cell is formed between the bare surface directly under the jet (anode) and the adjacent filmed surface (cathode). These jet tests give more dependable information, if natural sea water is continuously supplied to the equipment. 

The CMC plate was cut into dog bone shaped specimens using a water jet. Test specimens for fatigue test had thickness, width and gage length of 2.8, 10.2, 30 mm. respectively, and total... 

Figure 10 Comparison of two different designs of a submerged jet test (a) after Forsythe and Hertwig (1949) (b) after Gwyn...

Figure 13 Influence of the static bed height on jet attrition of spent FCC catalyst in a submerged jet test facility D = 0.05m, Mqj = lOOm/s, = 2mm). (Werther and Xi, 1993.)...

Finally, Zhang et al. [58] performed a water jet test to evaluate the robustness of their superhydrophobic aluminum alloys. The samples were fixed on a substrate tilted at 45° and placed 5 cm below a water pipe (inner diameter 4 mm), and then jetted for 10 min at different pressures (10-100 kPa). The pressure 25 kPa was selected because according to the authors calculations it corresponds to a heavy thxmderstorm. The water APCA remained greater than 150° up to 75 kPa for 10 min. However,... 

When coating TPO in Europe, usually a combination of some type of pretreatment plus 2K adhesion primers are used. The pretreatment provides optimum adhesion to even pass hot-water jet tests in which scribed painted parts are exposed to 100 percent relative humidity for ten days at 40°C before being... 

Figure 14. (a) Schematic representation of a typical arc-jet testing set-up [Zhang, 2008]. Experimental set-up for arc-jet testing (a) before the test (b) during the test (c) hemispherical HfB sample used for arc-jet testing, radius of curvature R = 7.5 mm [Savino, 2008]... 

Savino, R., Fumo, M. D. S., Silvestroni, L., Sciti, D. (2008). Arc-jet testing on HfBj and HfC-hased ultra-high temperature ceramic materials. Journal of the European Ceramic Society, 28,1899-1907. doi 10.1016/j.jeurceramsoc.2007.11.021. 

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