Determining of the optimum performance of a nano scale irreversible Dual cycle with quantum gases as working fluid by using different methods

2015 ◽  
Vol 433 ◽  
pp. 247-258 ◽  
Author(s):  
Emin Açıkkalp ◽  
Necmettin Caner
Keyword(s):  
Quantum Gases ◽  
Working Fluid ◽  
Optimum Performance ◽  
Nano Scale ◽  
Dual Cycle

scholarly journals Thermodynamic analysis and optimization of an irreversible nano scale dual cycle operating with Maxwell-Boltzmann gas

2017 ◽  
Vol 18 (2) ◽  
pp. 212 ◽  
Author(s):  
Mohammad H. Ahmadi ◽  
Mohammad Ali Ahmadi ◽  
Fathollah Pourfayaz ◽  
Michel Feidt ◽  
Emin Acıkkalp
Keyword(s):  
Thermodynamic Analysis ◽  
Nano Scale ◽  
Boltzmann Gas ◽  
Dual Cycle

Investigation and optimization of performance of nano-scale Stirling refrigerator using working fluid as Maxwell–Boltzmann gases

2017 ◽  
Vol 483 ◽  
pp. 337-350 ◽  
Author(s):  
Mohammad H. Ahmadi ◽  
Mohammad Amin Nabakhteh ◽  
Mohammad-Ali Ahmadi ◽  
Fathollah Pourfayaz ◽  
Mokhtar Bidi
Keyword(s):  
Working Fluid ◽  
Nano Scale ◽  
Stirling Refrigerator

Experimental Investigation of Closed Loop Pulsating Heat Pipe With Nanofluids

2009 ◽  
Author(s):  
Hamed Jamshidi ◽  
Sajad Arabnejad ◽  
Mohammad Behshad Shafii ◽  
Yadollah Saboohi ◽  
Ramin Rasoulian
Keyword(s):  
Thermal Resistance ◽  
Heat Pipe ◽  
Closed Loop ◽  
Filling Ratio ◽  
Nano Particles ◽  
Working Fluid ◽  
Sudden Increase ◽  
Pulsating Heat Pipe ◽  
Optimum Performance ◽  
The Impact

In this paper, the effect of several different parameters on the thermal resistance of a Closed Loop Pulsating Heat Pipe (CLPHP) has been investigated. These parameters include the working fluid, the inclination angle, the filling ratio and the heat influx. Also, the impact of using nanofluids with different nano-particle concentrations has been analyzed. It was observed that a CLPHP can increase the heat transfer up to 11.5 times compared to an empty pipe. Optimum performance for a system with the water-silver nanofluid was achieved at conditions of 50% filling ratio and 0.9 K/W of thermal resistance, and for the water-titanium oxide system, these optimal conditions were found to be 40% filling ratio and 0.8 K/W of thermal resistance. In addition, the optimum performance for pure water occurs at a filling ratio of 40% and a thermal resistance of 1.15 K/W. The nanofluid reduces the thermal resistance by 30%. With a decrease in the concentration of nano-particles in the base fluid, the performance of the system decreases as well and the total thermal resistance increases. In low powers (under 20 W), the two-phase flow pattern inside the pipes was slug-plug, but in higher powers (over 30 W), this changed to an annular flow. The performance of the system was better in the annular mode, but there was a probability of dry out and sudden increase of condenser temperature.

Experimental study of thermohydraulic characteristics and irreversibility analysis of novel axial corrugated tube with spring tape inserts

2020 ◽  
Vol 92 (3) ◽  
pp. 30901
Author(s):  
Suvanjan Bhattacharyya ◽  
Debraj Sarkar ◽  
Ulavathi Shettar Mahabaleshwar ◽  
Manoj K. Soni ◽  
M. Mohanraj
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Thermal Performance ◽  
Working Fluid ◽  
The Novel ◽  
Heat Exchanger Tube ◽  
Heat Transfer Augmentation ◽  
Corrugated Tube ◽  
The Impact ◽  
Exchanger Tube

The current study experimentally investigates the heat transfer augmentation on the novel axial corrugated heat exchanger tube in which the spring tape is introduced. Air (Pr = 0.707) is used as a working fluid. In order to augment the thermohydraulic performance, a corrugated tube with inserts is offered. The experimental study is further extended by varying the important parameters like spring ratio (y = 1.5, 2.0, 2.5) and Reynolds number (Re = 10 000–52 000). The angular pitch between the two neighboring corrugations and the angle of the corrugation is kept constant through the experiments at β = 1200 and α = 600 respectively, while two different corrugations heights (h) are analyzed. While increasing the corrugation height and decreasing the spring ratio, the impact of the swirling effect improves the thermal performance of the system. The maximum thermal performance is obtained when the corrugation height is h = 0.2 and spring ratio y = 1.5. Eventually, correlations for predicting friction factor (f) and Nusselt number (Nu) are developed.

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