Oezbelge, Tuelay A.
Camciuenal, Guelden
The prediction of two-phase pressure drops is important in the design of fluidized beds, heat exchangers, slurry transport lines, annular risers in reactors, driers, and other applications of particulate flows. Experimental data for liquid-solid up-flows through annuli are very limited. In this study, a correlation was developed for predicting two-phase pressure drops via Euler number (Eutp) for liquid-solid suspension up-flows in the fully developed flow region of an annulus in terms of mixture Reynolds number (Rem), solid particle Froude number (Frp), ratio of particle diameter to hydraulic diameter, and ratio of area-averaged solids density in the tested cross-sectional flow area of the annulus to the average density of the feed slurry entering the annulus. The proposed correlation, having an accuracy of almost 25%, was obtained for water-feldspar dilute suspension up-flows in an annulus with a hydraulic diameter of 79.8mm and with feldspar particles (2400kg/m3 in material density and 0.072-0.138 mm in average diameter) at low concentrations.


Detecting stability of conical spouted beds based on information entropy theory
Savari, Chiya; Sotudeh-Gharebagh, Rahmat; Külah, Görkem; KÖKSAL, MURAT; Mostoufi, Navid (Elsevier BV, 2019-02-01)
Effects of particle size, particle density, gas inlet diameter and static bed height on the stability of operation in conical spouted beds were investigated through analyses of information entropy of pressure fluctuations. In this respect, the maximum information entropy of pressure fluctuations was used as a stability criterion. The results showed that stability of the bed increases with an increase in the maximum entropy. The maximum information entropy of pressure fluctuations increases with increasing p...
Orbey, H.; Orbey, N. (Informa UK Limited, 1989-3)
A data reduction technique is introduced for the evaluation of second virial coefficients of gases at subcritical temperatures. The method makes use of the vapor-liquid equilibrium data, i.e., temperature, saturation pressure, liquid and vapor molar volumes and can be used to obtain second virial coefficients of a wide variety of fluids including polar, associating and quantum gases. The calculated second virial coefficients are in good agreement with their counterparts from literature, which are obtained f...
Assessment of flow and heat transfer characteristics for proposed solid density distributions in dilute laminar slurry upflows through a concentric annulus
Eraslan, Ahmet Nedim (Elsevier BV, 2003-09-01)
A computational model is developed to predict the hydrodynamic and heat transfer characteristics of dilute liquid-solid laminar upflows through a concentric annulus. The dilute slurry is treated as a single phase Newtonian fluid of locally variable physical and thermal properties. Available experimental data of radial solid density distributions in dilute water-feldspar annular upflows is used in the model. Various important characteristics of laminar slurry flows were successfully predicted. It was also sh...
Effect of Gas Diffusion Layer Characteristics and Addition of Pore-Forming Agents on the Performance of Polymer Electrolyte Membrane Fuel Cells
Senguel, Erce; Erkan, Serdar; Eroğlu, İnci; BAÇ, NURCAN (Informa UK Limited, 2009-01-01)
The performance of five layer membrane electrode assemblies having different characteristics of gas diffusion layers was determined at 70 degrees C cell temperature and ambient pressure. The maximum power density at 0.6 V was 0.36 W/cm(2) for the membrane electrode assembly prepared with the gas diffusion layer having minimum thickness (SGL BC 30 type). On the other hand, the maximum power density at 0.5 V was 0.44 W/cm(2) for the membrane electrode assembly prepared with SGL BC 34 type gas diffusion layer....
Synthesis of ZSM-5 and SAPO-34 membranes in a high temperature-pressure recirculating-flow system
TOPUZ, BERNA; Onder, Aylin; Bowen, Travis C.; Kalıpçılar, Halil (Elsevier BV, 2017-01-01)
MFI and SAPO-34 type zeolite membranes were prepared on tubular alumina supports in a recirculating flow system at elevated temperatures and reported for the first time in the literature. During membrane synthesis, the synthesis mixture flowed between the reservoir and the membrane module, which includes the membrane support. The highest synthesis temperatures were 180 degrees C and 220 degrees C, and the corresponding system pressures were approximately 20 and 30 bar for MFI and SAPO-34, respectively. The ...
Citation Formats
T. A. Oezbelge and G. Camciuenal, “A NEW CORRELATION FOR TWO-PHASE PRESSURE DROPS IN FULLY DEVELOPED DILUTE SLURRY UP-FLOWS THROUGH AN ANNULUS,” CHEMICAL ENGINEERING COMMUNICATIONS, pp. 491–498, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/65285.