Direct Steam Generation in Parabolic Troughs: First Results of the DISS Project

2002 ◽  
Vol 124 (2) ◽  
pp. 134-139 ◽  
Author(s):  
M. Eck ◽  
W.-D. Steinmann
Keyword(s):  
Steady State ◽  
Controller Design ◽  
Experimental Results ◽  
Phase Flow ◽  
Simulation Studies ◽  
Steam Generation ◽  
Two Phase ◽  
State Tests ◽  
Direct Steam ◽  
First Results

This article presents the latest experimental results of the European DISS (DIrect Solar Steam) project. The experiments are subdivided into steady state and transient tests. The goal of the steady state tests is the investigation of the thermohydraulic phenomena of the occurring two phase flow, whereas the transient tests are needed for the controller design. The experimental results are compared to simulation studies. Implications for the plant operation will be discussed.

Direct Steam Generation in Parabolic Troughs: First Results of the DISS Project

2001 ◽  
Author(s):  
M. Eck ◽  
W.-D. Steinmann
Keyword(s):  
Steady State ◽  
Controller Design ◽  
Experimental Results ◽  
Phase Flow ◽  
Simulation Studies ◽  
Steam Generation ◽  
Two Phase ◽  
State Tests ◽  
Direct Steam ◽  
First Results

Abstract This article presents the latest experimental results of the European DISS (DIrect Solar Steam) project. The experiments are subdivided into steady state and transient tests. The goal of the steady state tests is the investigation of the thermohydraulic phenomena of the occurring two phase flow, whereas the transient tests are needed for the controller design. The experimental results are compared to simulation studies. Implications for the plant operation will be discussed.

Comparison of Two-Phase Flow Correlations for Thermo-Hydraulic Modeling of Direct Steam Generation in a Solar Parabolic Trough Collector System

2018 ◽  
Vol 10 (4) ◽  
Author(s):  
Bohra Nitin Kumar ◽  
K. S. Reddy
Keyword(s):  
Heat Transfer ◽  
Pressure Drop ◽  
Two Phase Flow ◽  
Hydraulic Modeling ◽  
Test Facility ◽  
Phase Flow ◽  
Steam Generation ◽  
Two Phase ◽  
Direct Steam ◽  
Flow Map

Direct steam generation (DSG) in parabolic trough collector (PTC) is an efficient and feasible option for solar thermal power generation as well as for industrial process heat supply. The two-phase flow inside the absorber tube complicates the thermo-hydraulic modeling of the DSG process. In the present work, a thermo-hydraulic model is developed for the DSG process in the receiver of a solar PTC. The two-phase flow in the evaporating section is analyzed using two empirical correlations of heat transfer and pressure drop, and a flow map integrated heat transfer and pressure drop model. The results of the thermo-hydraulic simulation using different two-phase heat transfer and pressure drop correlations were compared with experimental data from the direct solar steam (DISS) test facility at Plataforma Solar de Almeria (PSA), Spain. The test facility has collectors with aperture width of 5.76 m, focal length of 1.71 m, and absorber tube with inner and outer diameters of 50 mm and 70 mm, respectively. The simulation results using the aforementioned two-phase models were found to be satisfactory and consistent within the experimental uncertainty. The flow map based heat transfer model predicted the mean fluid temperature with root-mean-square error (RMSE) of 0.45% and 1.40%, for the cases considered in the present study. Whereas the flow pattern map based pressure drop model predicts the variation of pressure along the length of the collector with RMSE of 0.5% and 0.14%. Moreover, the flow pattern map based model predicts the different flow regimes paving a better understanding of the two-phase flow and helps in identifying the critical sections along the collector length.

scholarly journals Numerical simulation of evaporating two-phase flow: application to concentrated solar plants with direct steam generation

2014 ◽  
Vol 18 ◽  
pp. 03003
Author(s):  
Rémi Dinsenmeyer ◽  
Jean-François Fourmigué ◽  
Nadia Caney ◽  
Philippe Marty
Keyword(s):  
Numerical Simulation ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Steam Generation ◽  
Two Phase ◽  
Direct Steam

Random Forces Resulting From Internal Two-Phase Flow on Bends and Tees

2006 ◽  
Author(s):  
E. de Langre ◽  
J. L. Riverin ◽  
M. J. Pettigrew
Keyword(s):  
Two Phase Flow ◽  
Experimental Results ◽  
Time Dependent ◽  
Phase Flow ◽  
Water Mixture ◽  
Dimensionless Form ◽  
Two Phase ◽  
Practical Applications ◽  
Random Forces

The time dependent forces resulting from a two-phase air-water mixture flowing in an elbow and a tee are measured. Their magnitudes as well as their spectral contents are analyzed. Comparison is made with previous experimental results on similar systems. For practical applications a dimensionless form is proposed to relate the characteristics of these forces to the parameters defining the flow and the geometry of the piping.

Analysis of Transient Two-Phase Flow in Pressure Safety Valve Outlet Headers

2018 ◽  
Author(s):  
Maral Taghva ◽  
Lars Damkilde
Keyword(s):  
Steady State ◽  
Shock Waves ◽  
High Speed ◽  
Two Phase Flow ◽  
Safety Valve ◽  
Strong Shock ◽  
Flow Property ◽  
Phase Flow ◽  
Transient Pressure ◽  
Two Phase

To protect a pressurized system from overpressure, one of the most established strategies is to install a Pressure Safety Valve (PSV). Therefore, the excess pressure of the system is relieved through a vent pipe when PSV opens. The vent pipe is also called “PSV Outlet Header”. After the process starts, a transient two-phase flow is formed inside the outlet header consisting of high speed pressurized gas interacting with existing static air. The high-speed jet compresses the static air towards the end tail of the pipe until it is discharged to the ambiance and eventually, the steady state is achieved. Here, this transient process is investigated both analytically and numerically using the method of characteristics. Riemann’s solvers and Godunov’s method are utilized to establish the solution. Propagation of shock waves and flow property alterations are clearly demonstrated throughout the simulations. The results show strong shock waves as well as high transient pressure take place inside the outlet header. This is particularly important since it indicates the significance of accounting for shock waves and transient pressure, in contrast to commonly accepted steady state calculations. More precisely, shock waves and transient pressure could lead to failure, if the pipe thickness is chosen only based on conventional steady state calculations.

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