scholarly journals Pemodelan Penurunan Tekanan Brine di Dalam Pipa Injeksi pada Lapangan Panas Bumi Dieng

Jurnal MIPA ◽  
2017 ◽  
Vol 6 (2) ◽  
pp. 32
Author(s):  
Jeferson Polii
Keyword(s):  
Pressure Drop ◽  
Flow Line ◽  
Chemical Constituents ◽  
Temperature Drop ◽  
Fluid Pressure ◽  
Saturation Temperature ◽  
Geothermal Field ◽  
Chemical Pollution ◽  
Pressure Drops ◽  
Very High

Injeksi brine hasil dari fluida produksi panas bumi digunakan untuk mengisi volume pori batuan reservoir, mencegah penurunan tekanan batuan yang terlalu cepat, dan mencegah polusi panas dan polusi kimia pada lingkungan yang disebabkan oleh kandungan kimia tertentu pada brine. Pada pipa aliran brine terjadi penurunan tekanan fluida sepanjang aliran. Di lapangan panas bumi Dieng, konsentrasi silika sangat tinggi, sehingga penurunan temperatur saturasi memicu desposisi silika. Penurunan tekanan sepanjang pipa aliran brine dari pompa Vertikal Atas (VA) 7 ke pond di pad 29 di lapangan panas bumi Dieng akan menyebabkan penurunan temperatur saturasi, selain juga kehilangan panas secara alami. Perhitungan penurunan tekanan fluida brine berdasarkan perhitungan Harrison-Freeston dan metode dari Zhao, yang dikembangkan dengan algoritma menggunakan Macro Excel. Sehingga dengan memodelkan penurunan tekanan sepanjang pipa alir, dapat dikembangkan untuk perhitungan penurunan temperatur dan pengendapan silika di pipa aliran brine untuk injeksi panas bumi.Brine injection from geothermal production fluids is used to fill reservoir pore rock volumes, preventing rapid rock pressure drops, and preventing heat pollution and chemical pollution in the environment caused by certain chemical constituents in the brine. Decrease fluid pressure along the flow on the brine flow pipe. In the Dieng geothermal field, the silica concentration is very high, so the decrease in saturation temperature triggers the silica desposition. The pressure drop along the brine flow pipe from the Upper Vertical (VA) 7 pump to the pond in pad 29 in Dieng geothermal field will cause a decrease in saturation temperature, as well as natural heat loss. The calculation of the decrease in brine fluid pressure based on Harrison-Freeston calculations and methods of Zhao, developed with algorithms using Macro Excel. By modeling the pressure drop along the flow line, it can be developed for the calculation of temperature drop and deposition of silica in the brine flow pipe for geothermal injection

Pressure Drop During Refrigerant Condensation Inside Horizontal Smooth, Helical Microfin, and Herringbone Microfin Tubes

2004 ◽  
Vol 126 (5) ◽  
pp. 687-696 ◽  
Author(s):  
Jonathan A. Olivier ◽  
Leon Liebenberg ◽  
Mark A. Kedzierski ◽  
Josua P. Meyer
Keyword(s):  
Heat Exchanger ◽  
Pressure Drop ◽  
Saturation Temperature ◽  
Mean Deviation ◽  
Pressure Gradients ◽  
Test Results ◽  
Pressure Drops ◽  
Mass Fluxes ◽  
R 134A ◽  
Microfin Tubes

This paper presents a study of pressure drops during condensation inside a smooth, an 18-deg helical microfin, and a herringbone microfin tube. Measurements were conducted with refrigerant flowing through the tube of a concentric heat exchanger, with water flowing in a counterflow direction in the annulus. Each tube was part of a condenser consisting of eight subcondensers with instrumentation preceding each subcondenser. Three refrigerants were used, namely, R-22, R-407C, and R-134a, all operating at a saturation temperature of 40 °C with mass fluxes ranging from 400 to 800kg/m2 s. Inlet qualities ranged from 0.85 to 0.95 and outlet qualities ranged from 0.05 to 0.15. The test results showed that on average for the three refrigerants the pressure gradients of the herringbone microfin tube were about 79% higher than that of the smooth tube and about 27% higher than that of the helical microfin tube. Further, a correlation from the literature for predicting pressure drops inside a helical microfin tube was modified for the herringbone microfin tube. The modified correlation predicted the data to within an error of 1% and had an absolute mean deviation of 6.8%. This modified correlation compared well with a correlation from the literature that predicted the data to within an error of 7%.

scholarly journals Pressure Drops in Two-Phase Gas–Liquid Flow through Channels Filled with Open-Cell Metal Foams

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2419
Author(s):  
Roman Dyga ◽  
Sebastian Brol
Keyword(s):  
Pressure Drop ◽  
Liquid Flow ◽  
Single Phase ◽  
Fluid Pressure ◽  
Metal Foams ◽  
Geometrical Parameters ◽  
Two Phase ◽  
Pressure Drops ◽  
Flow Through ◽  
Gas Liquid Flow

This paper describes experimental investigations of single-phase and two-phase gas–liquid flow through channels with a diameter of 20 mm and length of 2690 mm, filled with metal foams. Three types of aluminium foams with pore densities of 20, 30 and 40 PPI and porosities ranging from 29.9% to 94.3% were used. Air, water and oil were pumped through the foams. The tests covered laminar, transitional and turbulent flow. We demonstrated that the Reynolds number, in which the hydraulic dimension should be defined based on foam porosity and pore diameter de = ϕdp/(1 − ϕ), can be used as a flow regime assessment criterion. It has been found that fluid pressure drops when flowing through metal foams significantly depends on the cell size and porosity of the foam, as well as the shape of the foam skeleton. The flow patterns had a significant influence on the pressure drop. Among other things, we observed a smaller pressure drop when plug flow changed to stratified flow. We developed a model to describe pressure drop in flow through metal foams. As per the proposed methodology, pressure drop in single-phase flow should be determined based on the friction factor, taking into account the geometrical parameters of the foams. We propose to calculate pressure drop in gas–liquid flow as the sum of pressure drops in gas and liquid pressure drop corrected by the drop amplification factor.

scholarly journals Investigations on mixture preparation for two phase adiabatic pressure drop of R134a flowing in 5 mm diameter channel

2017 ◽  
Vol 38 (3) ◽  
pp. 101-118 ◽  
Author(s):  
Tomasz Muszyński ◽  
Rafał Andrzejczyk ◽  
Carlos A. Dorao
Keyword(s):  
Pressure Drop ◽  
High Speed ◽  
Saturation Temperature ◽  
High Speed Camera ◽  
Two Phase ◽  
Pressure Drops ◽  
Adiabatic Flow ◽  
Frictional Pressure Drop ◽  
Mixture Preparation ◽  
Diameter Channel

AbstractThe article presents detailed two-phase adiabatic pressure drops data for refrigerant R134a. Study cases have been set for a mass flux varying from 200 to 400 kg/m2s, at the saturation temperature of 19.4 °C. Obtained experimental data was compared with the available correlations from the literature for the frictional pressure drop during adiabatic flow. Influence of mixture preparation on pressure drop was investigated, for varying inlet subcooling temperature in the heated section. The flow patterns have also been obtained by means of a high-speed camera placed in the visualization section and compared with literature observations.

scholarly journals Pressure Drop of a Refrigerant Flowing Vertically Upward and Downward in Small Circular, Rectangular, and Triangular Tubes

2021 ◽  
Vol 11 (11) ◽  
pp. 5195
Author(s):  
Koji Enoki
Keyword(s):  
Pressure Drop ◽  
Cross Sections ◽  
High Performance ◽  
Measurement Data ◽  
Saturation Temperature ◽  
Two Phase ◽  
Pressure Drops ◽  
Frictional Pressure Drop ◽  
Mass Fluxes ◽  
Mini Channels

In the present study, experiments were performed to examine the characteristics of the two-phase frictional pressure drop of an R410A refrigerant flowing vertically upward and downward for the development of a high-performance heat exchanger using small tubes or mini-channels for air-conditioning systems. The cross-sections of copper test tubes were 0.5, 0.7, 1.0, 1.5, and 2.0 mm circular tubes, and rectangular and triangular tubes with hydraulic diameters of 1.04 and 0.88 mm, respectively. The frictional pressure drops were measured in the range of mass fluxes of 30–400 kg·m−2·s−1, with qualities from 0.05 to 0.9 and a saturation temperature of 10 °C. The characteristics of the measured pressure drops were compared in different inner diameters, cross-section shapes, and flow directions. In addition, Chisholm’s parameter and various modified Chisholm’s parameters for small tubes were examined to determine whether or not they reproduced our measurement data.

Experimental and Computational Analyses of Pressure Differentials in Flexible Ducts With Different Bent Angles

2007 ◽  
Author(s):  
Ray R. Taghavi ◽  
Wonjin Jin ◽  
Mario A. Medina
Keyword(s):  
Pressure Drop ◽  
Static Pressure ◽  
Complex Geometry ◽  
Analysis Data ◽  
Secondary Flows ◽  
Low Flow ◽  
Pressure Drops ◽  
Pressure Distributions ◽  
Geometrical Effects ◽  
Cfd Analyses

A set of experimental analyses was conducted to determine static pressure drops inside non-metallic flexible, spiral wire helix core ducts, with different bent angles. In addition, Computational Fluid Dynamics (CFD) solutions were performed and verified by comparing them to the experimental data. The CFD computations were carried out to produce more systematic pressure drop information through these complex-geometry ducts. The experimental setup was constructed according to ASHRAE Standard 120-1999. Five different bent angles (0, 30, 45, 60, and 90 degrees) were tested at relatively low flow rates (11 to 89 CFM). Also, two different bent radii and duct lengths were tested to study flexible duct geometrical effects on static pressure drops. FLUENT 6.2, using RANS based two equations - RNG k-ε model, was used for the CFD analyses. The experimental and CFD results showed that larger bent angles produced larger static pressure drops in the flexible ducts. CFD analysis data were found to be in relatively good agreement with the experimental results for all bent angle cases. However, the deviations became slightly larger at higher velocity regimes and at the longer test sections. Overall, static pressure drop for longer length cases were approximately 0.01in.H2O higher when compared to shorter cases because of the increase in resistance to the flow. Also, the CFD simulations captured more pronounced static pressure drops that were produced along the sharper turns. The stronger secondary flows, which resulted from higher and lower static pressure distributions in the outer and inner surfaces, respectively, contributed to these higher pressure drops.

Embedded Two-Phase Cooling of High Flux Electronics via Micro-Enabled Surfaces and Fluid Delivery Systems (FEEDS)

2015 ◽  
Author(s):  
Raphael Mandel ◽  
Serguei Dessiatoun ◽  
Patrick McCluskey ◽  
Michael Ohadi
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Pressure Drop ◽  
Saturation Temperature ◽  
Absolute Pressure ◽  
High Flux ◽  
Vapor Quality ◽  
Two Phase ◽  
Fluid Delivery ◽  
Future Work

This work presents the experimental design and testing of a two-phase, embedded manifold-microchannel cooler for cooling of high flux electronics. The ultimate goal of this work is to achieve 0.025 cm2-K/W thermal resistance at 1 kW/cm2 heat flux and evaporator exit vapor qualities at or exceeding 90% at less than 10% absolute pressure drop. While the ultimate goal is to obtain a working two-phase embedded cooler, the system was first tested in single-phase mode to validate system performance via comparison of experimentally measured heat transfer coefficient and pressure drop to the values predicted by CFD simulations. Upon validation, the system was tested in two phase mode using R245fa at 30°C saturation temperature and achieved in excess of 1 kW/cm2 heat flux at 45% vapor quality. Future work will focus on increasing the exit vapor quality as well as use of SiC for the heat transfer surface upon completion of current experiments with Si.

Experimental Study of Evaporation Heat Transfer Characteristics and Pressure Drops of R410A and R134a in a Multiport Mini-Channel

2009 ◽  
Author(s):  
Jatuporn Kaew-On ◽  
Somchai Wongwises
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Pressure Drop ◽  
Transfer Coefficient ◽  
Transfer Coefficients ◽  
Pressure Drops ◽  
Heat Transfer Coefficients ◽  
Evaporation Heat ◽  
Evaporation Heat Transfer ◽  
R 134A

The evaporation heat transfer coefficients and pressure drops of R-410A and R-134a flowing through a horizontal-aluminium rectangular multiport mini-channel having a hydraulic diameter of 3.48 mm are experimentally investigated. The test runs are done at refrigerant mass fluxes ranging between 200 and 400 kg/m2s. The heat fluxes are between 5 and 14.25 kW/m2, and refrigerant saturation temperatures are between 10 and 30 °C. The effects of the refrigerant vapour quality, mass flux, saturation temperature and imposed heat flux on the measured heat transfer coefficient and pressure drop are investigated. The experimental data show that in the same conditions, the heat transfer coefficients of R-410A are about 20–50% higher than those of R-134a, whereas the pressure drops of R-410A are around 50–100% lower than those of R-134a. The new correlations for the evaporation heat transfer coefficient and pressure drop of R-410A and R-134a in a multiport mini-channel are proposed for practical applications.

Swirling Annular Flow in a Steam Separator

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Hironobu Kataoka ◽  
Yusuke Shinkai ◽  
Shigeo Hosokawa ◽  
Akio Tomiyama
Keyword(s):  
Pressure Drop ◽  
Annular Flow ◽  
Nuclear Reactor ◽  
Water Pressure ◽  
Interfacial Friction ◽  
Pressure Drops ◽  
Pressure Transducers ◽  
Ring Configuration ◽  
Film Flows ◽  
Steam Separator

Effects of pick-off ring configuration on the separator performance of a downscaled model of a steam separator for a boiling water nuclear reactor are examined using various types of pick-off rings. The experiments are conducted using air and water. Pressure drops in a barrel and a diffuser and diameters and velocities of droplets at the exit of the barrel are measured using differential pressure transducers and particle Doppler anemometry, respectively. The separator performance does not depend on the shape of the pick-off ring but strongly depends on the width of the gap between the pick-off ring and the barrel wall. The pressure drop in the barrel is well evaluated using the interfacial friction factor for unstable film flows. Carry-under can be estimated using a droplet velocity distribution at the exit of the separator.

Effect of Lateral Pipe-Soil Interaction on Controlled Lateral Buckling Using Pre-Deformed Pipeline

2018 ◽  
Author(s):  
Jayden Chee ◽  
Alastair Walker ◽  
David White
Keyword(s):  
High Temperature ◽  
Longitudinal Strain ◽  
Flow Line ◽  
Soft Clay ◽  
Axial Stiffness ◽  
Lateral Buckling ◽  
Novel Approach ◽  
Different Response ◽  
Local Variability ◽  
Very High

A novel approach to eliminate the onset of global buckling in pipelines is investigated in the paper. The method is based on pre-deforming a pipeline continuously with a specific wavelength and amplitude prior to installation on the seabed. The response of the pipeline to applied high temperature and pressure was studied in conjunction with variations in the lateral pipe-soil interaction (PSI) — both as uniform friction along the pipe and also with locally varying friction. Pipe and seabed parameters representing a typical wet-insulated infield flow line on soft clay are used. The pre-deformed pipeline has a higher buckle initiation temperature compared to a straight pipeline due to the reduced effective axial force build-up resulting from the low axial stiffness generated by the pre-deformed lobes along the pipeline. The results from this paper show that the strains in the pre-deformed pipeline are not significantly affected by the local variability of lateral PSI but rather by the global mean PSI. At a typical lateral soil resistance, i.e. a friction coefficient of 0.5, lateral buckling occurs at a very high temperature level that is not common in the subsea operation. At a very low friction, i.e. 0.1, lateral buckling occurs at a lower operating temperature but the strain is insignificant. The longitudinal strain of the pipeline is not highly sensitive to the lateral PSI, which is a quite different response to an initially straight pipeline. Therefore, this method could prove to be a valuable tool for the subsea industry as it enables the pipeline to be installed and operated safely at very high temperatures without the need for lateral buckling design and installation of expensive structures as buckle initiators. Even if the pre-deformed pipeline buckles at a very high temperature, during cycles of heat-up and cool-down the buckle shape ‘shakes down’ by geometric rearrangement to minimize the energy, and in doing so creates a series of ‘short pipelines’ in which the longitudinal strain is self-controlled. The system is therefore shown to be very robust in the conditions investigated and not affected by one of the biggest unknowns in seabed pipeline engineering, which is the local variability in lateral PSI.

Sign in / Sign up

Export Citation Format

Share Document