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51.
This paper presents alternative approach in heat transfer analysis of plate heat exchangers. In order to obtain heat transfer
rate and effectiveness values of plate heat exchanger, neural network (NN) approach was used. Experimentally, system used
in plate heat exchanger for heating and cooling applications was designed and constructed. Experimental data were used for
training and testing network. The training and validation were performed with good accuracy. The correlation coefficient obtained
when unknown data were applied to the networks was 0.9994 for heat transfer rate and 0.9976 for effectiveness, which is very
satisfactory. Using the weights obtained from the trained network, a new formulation is presented for determination of heat
transfer rate and effectiveness. This formulation can provide simplicity in thermal analysis of plate heat exchanger. The
presented procedure can also help to heat exchanger designer and manufacturer. 相似文献
52.
Mediterranean Journal of Mathematics - 相似文献
53.
Kubra Koyuncu H. Ibrahim Unal O. Yunus Gumus Ozlem Erol Bekir Sari Turgay Ergin 《先进技术聚合物》2012,23(11):1464-1472
In this study, poly(vinyl chloride) (PVC), polyindole (PIN), and PVC/PIN conducting composites having five different compositions were used. Particle sizes, densities, dielectric constants, and sedimentation ratios of the materials were determined. The zeta‐potentials of the samples were measured in aqueous and nonaqueous (silicone oil [SO]) media. The dispersions prepared in SO were subjected to external electric field strength, and their electrorheological properties were investigated. Then the effects of dispersed particle volume fraction, shear rate, external electric field strength, frequency, and temperature onto electrorheological activities of the dispersions were examined. Further, creep and creep‐recovery tests were applied to the PIN/SO and PVC/PIN/SO dispersions, and reversible viscoelastic deformations were observed. Finally, the vibration damping capacity of PVC (66%)/PIN (34%)/SO dispersion system was tested by using an automobile shock absorber. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
54.
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56.
Subasi Abdussamet Manay Eyuphan Elbas Seyma Sahin Bayram 《Journal of Thermal Analysis and Calorimetry》2021,145(5):2451-2465
Journal of Thermal Analysis and Calorimetry - An experimental research was performed to examine the effect of hydrodynamically and thermally developing distilled water-based SiO $$_2$$ nanofluid... 相似文献
57.
Investigation of the spectral,optical and surface morphology properties of the N,N′‐Dipentyl‐3,4,9,10‐perylenedicarboximide small molecule for optoelectronic applications
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Bayram Gündüz 《先进技术聚合物》2016,27(2):144-155
The spectral and optical properties of the solutions of the N,N′‐Dipentyl‐3,4,9,10‐perylenedicarboximide (PTCDI‐C5) small molecule for different molarities were investigated in detail. The significant spectral parameters such as molar/mass extinction coefficients, absorption coefficient, electric dipole line strength, and oscillator strength of the PTCDI‐C5 molecule were calculated. The absorption bands of PTCDI‐C5 show vibronic structures with seven peaks at 2.08, 2.35, 2.53, 2.70, 2.86, 3.32, and 3.86 eV, respectively. The electronic spectra of the PTCDI‐C5 can be characterized by two basic regions as visible and Soret band. Effects of the molarities on the significant many optical parameters were investigated in detail. The direct and indirect allowed optical band gaps of the PTCDI‐C5 decrease with increasing molarity. Then, surface morphology properties were investigated and calculated roughness parameters of the PTCDI‐C5 film. Finally, we discussed for optoelectronic applications of these parameters, and this study was compared with the similar and related studies in the literature. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
58.
S. Akkoyun T. Bayram S. O. Kara N. Yildiz 《Physics of Particles and Nuclei Letters》2013,10(6):528-534
Nuclear shape transition has been actively studied in the past decade. In particular, the understanding of this phenomenon from a microscopic point of view is of great importance. Because of this reason, many works have been employed to investigate shape phase transition in nuclei within the relativistic and nonrelativistic mean field models by examining potential energy curves (PECs). In this paper, by using layered feed-forward neural networks (LFNNs), we have constructed consistent empirical physical formulas (EPFs) for the PECs of 38–66Ti calculated by the Hartree-Fock-Bogoliubov (HFB) method with SLy4 Skyrme forces. It has been seen that the PECs obtained by neural network method are compatible with those of HFB calculations. 相似文献
59.
In this article we investigate Vranceanu rotation surfaces with pointwise 1- type Gauss map in Euclidean 4-space $
\mathbb{E}^4
$
\mathbb{E}^4
. We show that a Vranceanu rotation surface M has harmonic Gauss map if and only if M is a part of a plane. Further, we give necessary and sufficent conditions for Vranceanu rotation surface to have pointwise
1-type Gauss map. 相似文献
60.
Yih KH Hamdemir IK Mondloch JE Bayram E Özkar S Vasić R Frenkel AI Anderson OP Finke RG 《Inorganic chemistry》2012,51(5):3186-3193
Reported herein is the synthesis of the previously unknown [Ir(1,5-COD)(μ-H)](4) (where 1,5-COD = 1,5-cyclooctadiene), from commercially available [Ir(1,5-COD)Cl](2) and LiBEt(3)H in the presence of excess 1,5-COD in 78% initial, and 55% recrystallized, yield plus its unequivocal characterization via single-crystal X-ray diffraction (XRD), X-ray absorption fine structure (XAFS) spectroscopy, electrospray/atmospheric pressure chemical ionization mass spectrometry (ESI-MS), and UV-vis, IR, and nuclear magnetic resonance (NMR) spectroscopies. The resultant product parallels--but the successful synthesis is different from, vide infra--that of the known and valuable Rh congener precatalyst and synthon, [Rh(1,5-COD)(μ-H)](4). Extensive characterization reveals that a black crystal of [Ir(1,5-COD)(μ-H)](4) is composed of a distorted tetrahedral, D(2d) symmetry Ir(4) core with two long [2.90728(17) and 2.91138(17) ?] and four short Ir-Ir [2.78680 (12)-2.78798(12) ?] bond distances. One 1,5-COD and two edge-bridging hydrides are bound to each Ir atom; the Ir-H-Ir span the shorter Ir-Ir bond distances. XAFS provides excellent agreement with the XRD-obtained Ir(4)-core structure, results which provide both considerable confidence in the XAFS methodology and set the stage for future XAFS in applications employing this Ir(4)H(4) and related tetranuclear clusters. The [Ir(1,5-COD)(μ-H)](4) complex is of interest for at least five reasons, as detailed in the Conclusions section. 相似文献