Dynamic Modelling and Simulation of a Multistage Flash Desalination System

As the leading thermal desalination method, multistage flash (MSF) desalination plays an important role in obtaining freshwater. Its dynamic modeling and dynamic performance prediction are quite important for the optimal control, real-time optimal operation, maintenance, and fault diagnosis of MSF plants. In this study, a detailed mathematical model of the MSF system, based on the first principle and its treatment strategy, was established to obtain transient performance change quickly. Firstly, the whole MSF system was divided into four parts, which are brine heat exchanger, flashing stage room, mixed and split modulate, and physical parameter modulate. Secondly, based on mass, energy, and momentum conservation laws, the dynamic correlation equations were formulated and then put together for a simultaneous solution. Next, with the established model, the performance of a brine-recirculation (BR)-MSF plant with 16-stage flash chambers was simulated and compared for validation. Finally, with the validated model and the simultaneous solution method, dynamic simulation and analysis were carried out to respond to the dynamic change of feed seawater temperature, feed seawater concentration, recycle stream mass flow rate, and steam temperature. The dynamic response curves of TBT (top brine temperature), BBT (bottom brine temperature), the temperature of flashing brine at previous stages, and distillate mass flow rate at previous stages were obtained, which specifically reflect the dynamic characteristics of the system. The presented dynamic model and its treatment can provide better analysis for the real-time optimal operation and control of the MSF system to achieve lower operational cost and more stable freshwater quality.

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Electrostatic Sensor for Real–Time Mass Flow Rate Measurement of Particle Conveying in Pneumatic Pipeline

Jurnal Teknologi ◽

10.11113/jt.v41.712 ◽

2012 ◽

Cited By ~ 2

Author(s):

Mohd. Fua’ad Rahmat ◽

Wee Lee Yaw

Keyword(s):

Real Time ◽

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Cross Correlation ◽

High Accuracy ◽

Industrial Processes ◽

Rate Measurement ◽

Flow Rate Measurement ◽

Controlled Flow

This paper discussed the electrostatic sensors that have been constructed for real–time mass flow rate measurement of particle conveying in a Pneumatic pipeline. Many industrial processes require continuous, smooth, and consistent delivery of solids materials with a high accuracy of controlled flow rate. This requirement can only be achieved by installing a proper measurement system. Electrostatic sensor offers the most inexpensive and simplest means of measuring solids flows in pipes. Key words: Electrostatic sensor, cross-correlation, peripheral velocity

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Near-Real-Time Detection of Tephra Eruption Onset and Mass Flow Rate Using Microwave Weather Radar and Infrasonic Arrays

IEEE Transactions on Geoscience and Remote Sensing ◽

10.1109/tgrs.2016.2578282 ◽

2016 ◽

Vol 54 (11) ◽

pp. 6292-6306 ◽

Cited By ~ 4

Author(s):

Frank S. Marzano ◽

Errico Picciotti ◽

Saverio Di Fabio ◽

Mario Montopoli ◽

Luigi Mereu ◽

...

Keyword(s):

Real Time ◽

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Weather Radar ◽

Real Time Detection

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Real time mass flow rate measurement using multiple fan beam optical tomography

ISA Transactions ◽

10.1016/j.isatra.2007.05.005 ◽

2008 ◽

Vol 47 (1) ◽

pp. 3-14 ◽

Cited By ~ 13

Author(s):

R. Abdul Rahim ◽

L.C. Leong ◽

K.S. Chan ◽

M.H. Rahiman ◽

J.F. Pang

Keyword(s):

Real Time ◽

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Optical Tomography ◽

Rate Measurement ◽

Flow Rate Measurement

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Investigation of Fuel Distribution in Partially Premixed Swirled Burner With Pilot Flame

Volume 4B: Combustion, Fuels and Emissions ◽

10.1115/gt2016-57478 ◽

2016 ◽

Cited By ~ 1

Author(s):

Sergey S. Matveev ◽

Ivan A. Zubrilin ◽

Mikhail Yu. Orlov ◽

Sergey G. Matveev ◽

Ivan V. Chechet

Keyword(s):

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Experimental Measurement ◽

Central Body ◽

Combustion Efficiency ◽

Optimal Operation ◽

Fuel Distribution ◽

Fuel Mass ◽

Partially Premixed

At this paper, results of investigation of influence fuel distribution for combustion efficiency in model gas turbine burner with central body are presented. The burner is used for burning partially premixed lean mixture. The first part of gaseous fuel is injected into the central body with pilot flame (first fuel inlet) and the second part into the swirler (second fuel inlet). Study was performed with using CDF and experimental measurement. Experimental measurement was carried out with using chromatography equipment for concentration of combustion products determination. Experiment was conducted two case with first fuel inlet mass flow rate of 20% and 50% of the total fuel mass flow rate. Total fuel consumption was a constant at all case, total equivalence ratio was φ=0.625. At inline heater provides preheated air up from 328K to 523K. Numerical simulation of the flow parameters was carried out using Reynolds Stress for turbulence modeling and Flamelet Generated Manifold approach for combusting modeling. CFD calculation was conducted first fuel inlet mass flow rate of 0 to 100% of the total fuel mass flow rate and with preheated air up from 328K to 1173K. Weight average emission pollutant and combustion efficiency were compared to experiment data. Optimal operation of the burner have been found by the study.

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Physical Model for Real-Time Simultaneous Estimation of Intake Mass and Cylinder Pressure in an SI Engine

ASME 2016 Internal Combustion Engine Fall Technical Conference ◽

10.1115/icef2016-9396 ◽

2016 ◽

Cited By ~ 1

Author(s):

Shuonan Xu ◽

Zhe Wang ◽

Robert Prucka ◽

Zoran Filipi ◽

Michael Prucka ◽

...

Keyword(s):

Real Time ◽

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Air Flow ◽

Estimation Algorithm ◽

Simultaneous Estimation ◽

Cylinder Pressure ◽

Pressure Transducers ◽

Prediction Techniques

Stringent emission regulations require spark ignited (SI) engines to operate at stoichiometry to enable the use of a three way catalyst (TWC). Thus, accurate prediction of the intake charge mass flow rate is paramount. Current speed-density air mass-flow prediction techniques require extensive calibration for predicting volumetric efficiency, while mass air flow (MAF) meter based approaches suffer from a loss of accuracy during transients. This work aims to provide an alternative, i.e. a model based air charge estimation algorithm that can reduce calibration effort and provide a universal solution across engine platforms. An additional objective is to minimize the number of required sensors and associated cost. The foundation is established with a 0-D physics-based air charge model, where air flow through intake and exhaust valves is modeled on a crank-angle basis, without the need to measure in-cylinder pressure. The proposed algorithm solves differential equations for cylinder pressure and mass flow rate in/out of the cylinder to simultaneously obtain instantaneous pressure and mass-flow estimations, hence eliminating the need to install cylinder pressure transducers. An additional benefit is the robustness of the new model, due to its ability to self-compensate for an error in the intake runner pressure or initial estimation of the cylinder pressure. The model has been validated with GT-Power simulations and steady-state engine tests with multiple actuator sweeps. Transient tests and real-time implementations were performed as well.

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