Oil entrainment in vertical refrigerant piping

2000-12-01
Kesim, SC
Albayrak, Kahraman
Ileri, A
Show full item record
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
235
views
0
downloads
The aim of this study is to investigate the required refrigerant speed, hence minimum refrigeration load, for carrying the lubricating oil up in vertical sections of refrigerant lines. It is assumed that the downward flow of the thin oil layer over the inner surface of the riser due to gravity is to be balanced with the upward flow of the oil film due to the shear force created by the upward flow of the refrigerant vapor. Velocities are converted to refrigeration capacities by considering a saturated cycle between specified condenser and evaporator pressures. General relationships thus developed are enumerated for R134a by preparing minimum capacity tables for copper suction and discharge risers. (C) 2000 Elsevier Science Ltd and IIR. All rights reserved.
Refrigerating circuit, Piping, Vertical tube, Oil return, Refrigerant, Vapour, Speed, Calculation
https://hdl.handle.net/11511/31450
INTERNATIONAL JOURNAL OF REFRIGERATION-REVUE INTERNATIONALE DU FROID
Graduate School of Natural and Applied Sciences, Article

Suggestions

Shape Optimization of Reentry Vehicles to Minimize Heat Loading
Eyi, Sinan; Boyd, I D (2019-01-06)
The objective of the current study is to design an optimum reentry vehicle shape that minimizes heat loading subject to constraints on the maximum values of surface heat flux and temperature. A new heat loading formulation is developed for objective function evaluations. Axisymmetric Navier-Stokes and finite-rate chemical reaction equations are solved to evaluate the objective and constraint functions. The Menter SST turbulence model is employed for turbulence closure. A gradient-based method is used for op...
Cooling performance investigation of a two-pass rib-roughened channel
Kavas, İsa; Kurtuluş, Dilek Funda; Yasa, Tolga; Department of Aerospace Engineering (2015)
The performance of the modern aero-engines is highly dependent on the turbine inlet gas temperature. The higher temperature leads to more compact and efficient machines. Additionally, specific fuel consumption of the engine is decreased for the same thrust rating. However, the turbine inlet temperatures of the today’s engines are already beyond the material structural limits. Hence, the turbine section must be cooled down to acceptable levels. Various types of cooling methods are typically applied to the ga...
Experimental investigation of a pressure swirl atomizer spry
Marchione, T.; Allouis, Christophe Gerard; Amoresano, A.; Beretta, F. (2007-09-01)
The fuel injector has an important role in the process for an efficient combustion because it increases the specific surface area of the fuel and it allows one to reach high rates of mixing and evaporation. This paper has focused on the behavior of kerosene Jet A-1 spray produced by commercial pressure swirl atomizers in terms of mean diameter distributions, velocity component profiles, and cone angle variations over time. The analysis has been carried out experimentally with the aid of a phase-Doppler anem...
Optimization of energy production from an underground gas storage reservoir
Sınayuç, Çağlar; Kucukeksi, MS (2000-06-01)
The aim of this study is to supply the variable gas demand from an underground gas storage reservoir during heating season by an optimal selection of production rates. Because of the interaction of many influences, parameters, and previous decisions, determination of production rates becomes so involved that the manager can no longer use intuitive judgment. The objective, therefore, is to reach an optimum decision by applying the linear programming method in problem optimization.
Solids motion near the wall of high density circulating fluidized beds
Külah, Görkem; Grace, J R; Bi, H T (null; 2002-07-01)
This study was directed to the hydrodynamics of vertical risers, such as those used in catalytic cracking and other chemical reactors. The work was carried out in risers of 0.2 m and 0.076 m diameters with FCC particles of mean diameter 70 μm, primarily using optical fibre probes and solid tracer response measurements. The flow characteristics of high-density gas-solids systems were investigated in detail by measuring the local transient particle velocity, solids concentration and solids fluxes at different...
Citation Formats
S. Kesim, K. Albayrak, and A. Ileri, “Oil entrainment in vertical refrigerant piping,” INTERNATIONAL JOURNAL OF REFRIGERATION-REVUE INTERNATIONALE DU FROID, pp. 626–631, 2000, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31450.
METU IIS - Integrated Information Service open@metu.edu.tr