Injection Lines for 3000 bar System Pressure

MTZ worldwide ◽  
2021 ◽  
Vol 83 (1) ◽  
pp. 48-53
Author(s):  
Sebastian Brust ◽  
Hossein Karbasian ◽  
Steffen Zimmermann ◽  
Karl Meiwes
Keyword(s):  
System Pressure

A SYSTEM FOR PROTECTING AN OIL DIFFUSION PUMP AGAINST FAILURE OF THE MECHANICAL FORE PUMP, COOLING WATER, OR ELECTRICITY

1970 ◽  
Vol 28 ◽  
pp. 344-345
Author(s):  
W. C. Bigelow ◽  
F. B. Drogosz ◽  
S. Nitschke
Keyword(s):  
High Vacuum ◽  
Cooling Water ◽  
Effective Protection ◽  
Pump Line ◽  
Diffusion Pump ◽  
System Pressure ◽  
Control Relay ◽  
Vacuum Systems ◽  
Vacuum Gage ◽  
Pressure Switch

High vacuum systems with oil diffusion pumps usually have a pressure switch to protect against Insufficient cooling water; however, If left unattended for long periods of time, failure of the mechanical fore pump can occur with equally serious results. The device shown schematically in Fig. 1 has been found to give effective protection against both these failures, yet it is inexpensive and relatively simple to build and operate.With this system, pressure in the fore pump line is measured by thermocouple vacuum gage TVG (CVC G.TC-004) whose output is monitored by meter relay MRy (Weston 1092 Sensitrol) which is set to close if the pressure rises above about 0.2 torr. This energizes control relay CRy (Potter & Brumfield KA5Y 120VAC SPDT) cutting off power to solenoid-operated fore line valve Vf (Cenco 94280-4 Norm. Closed) which closes to prevent further leakage of air into the diffusion pump

Compressor Issues for Hydrogen Production and Transmission Through a Long Distance Pipeline Network

2008 ◽  
Vol 59 (4) ◽  
Author(s):  
Fred Starr ◽  
Calin-Cristian Cormos ◽  
Evangelos Tzimas ◽  
Stathis Peteves
Keyword(s):  
Pressure Ratio ◽  
High Strength Steels ◽  
High Strength ◽  
Energy System ◽  
Pipeline System ◽  
Hydrogen Energy ◽  
Long Distance ◽  
System Pressure ◽  
Production Of Hydrogen ◽  
Plant Exit

A hydrogen energy system will require the production of hydrogen from coal-based gasification plants and its transmission through long distance pipelines at 70 � 100 bar. To overcome some problems of current gasifiers, which are limited in pressure capability, two options are explored, in-plant compression of the syngas and compression of the hydrogen at the plant exit. It is shown that whereas in-plant compression using centrifugal machines is practical, this is not a solution when compressing hydrogen at the plant exit. This is because of the low molecular weight of the hydrogen. It is also shown that if centrifugal compressors are to be used in a pipeline system, pressure drops will need to be restricted as even an advanced two-stage centrifugal compressor will be limited to a pressure ratio of 1.2. High strength steels are suitable for the in-plant compressor, but aluminium alloy will be required for a hydrogen pipeline compressor.

Application of neural networks in predictions of brake wear particulate matter emission

2021 ◽  
pp. 095440702110363
Author(s):  
Saša Vasiljević ◽  
Jasna Glišović ◽  
Nadica Stojanović ◽  
Ivan Grujić
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Particulate Matter ◽  
Traffic Control ◽  
World Health ◽  
Vehicle Speed ◽  
System Pressure ◽  
The Neural Network ◽  
Vehicle Systems ◽  
Brake Wear

According to the World Health Organization, air pollution with PM10 and PM2.5 (PM-particulate matter) is a significant problem that can have serious consequences for human health. Vehicles, as one of the main sources of PM10 and PM2.5 emissions, pollute the air and the environment both by creating particles by burning fuel in the engine, and by wearing of various elements in some vehicle systems. In this paper, the authors conducted the prediction of the formation of PM10 and PM2.5 particles generated by the wear of the braking system using a neural network (Artificial Neural Networks (ANN)). In this case, the neural network model was created based on the generated particles that were measured experimentally, while the validity of the created neural network was checked by means of a comparative analysis of the experimentally measured amount of particles and the prediction results. The experimental results were obtained by testing on an inertial braking dynamometer, where braking was performed in several modes, that is under different braking parameters (simulated vehicle speed, brake system pressure, temperature, braking time, braking torque). During braking, the concentration of PM10 and PM2.5 particles was measured simultaneously. The total of 196 measurements were performed and these data were used for training, validation, and verification of the neural network. When it comes to simulation, a comparison of two types of neural networks was performed with one output and with two outputs. For each type, network training was conducted using three different algorithms of backpropagation methods. For each neural network, a comparison of the obtained experimental and simulation results was performed. More accurate prediction results were obtained by the single-output neural network for both particulate sizes, while the smallest error was found in the case of a trained neural network using the Levenberg-Marquardt backward propagation algorithm. The aim of creating such a prediction model is to prove that by using neural networks it is possible to predict the emission of particles generated by brake wear, which can be further used for modern traffic systems such as traffic control. In addition, this wear algorithm could be applied on other vehicle systems, such as a clutch or tires.

The Role of Porous Media in Homogenization of High Pressure Diesel Fuel Spray Combustion

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Navid Shahangian ◽  
Damon Honnery ◽  
Jamil Ghojel
Keyword(s):  
High Pressure ◽  
Porous Media ◽  
High Speed ◽  
Fuel Spray ◽  
Compression Ignition Engines ◽  
System Pressure ◽  
Novel Approach ◽  
Air Mixing ◽  
The Media

Interest is growing in the benefits of homogeneous charge compression ignition engines. In this paper, we investigate a novel approach to the development of a homogenous charge-like environment through the use of porous media. The primary purpose of the media is to enhance the spread as well as the evaporation process of the high pressure fuel spray to achieve charge homogenization. In this paper, we show through high speed visualizations of both cold and hot spray events, how porous media interactions can give rise to greater fuel air mixing and what role system pressure and temperature plays in further enhancing this process.

Paper 15: Recent Research and Development in Truck Engine Cooling

1969 ◽  
Vol 184 (1) ◽  
pp. 117-124 ◽  
Author(s):  
S. R. G. Taylor
Keyword(s):  
Coolant Temperature ◽  
Analytical Prediction ◽  
Cooling Performance ◽  
Pump Speed ◽  
Power Characteristics ◽  
Engine Cooling ◽  
System Pressure ◽  
Component Design ◽  
Additional Resistance ◽  
Water Pumps

To improve economically the cooling performance of trucks an analytical approach was used to assist development. The component tests undertaken included the complete net pressure and power characteristics of two engine water pumps and four engine fans, the heat transfer and pressure drop performances over appropriate flow ranges of some 14 radiators, the additional resistance to air flow offered by two noise shields, and studies of the effects of pump speed, coolant temperature, system pressure, thermostat resistance, and by-pass resistance on radiator water flow with three different engines. The apparatus and methods used for each type of test are outlined. Using the above and other existing data, cooling performance was predicted for some 80 different configurations and conditions, and fan power consumption was predicted for several of these. These results enabled component design and manufacturing problems to be identified and the selection of the most promising configurations for actual development testing. The agreement between the predicted and actual cooling performances is discussed. The use of computer programmes in component testing and analytical prediction is mentioned, and various possible developments in future cooling systems of still higher performance are discussed.

LES and RANS Assessment of Rib Cooled Channel Related to SGT-800 Combustor Liner

2011 ◽  
Author(s):  
Daniel Lo¨rstad
Keyword(s):  
Pressure Drop ◽  
Cooling System ◽  
Large Temperature ◽  
Internal Cooling ◽  
Low Frequencies ◽  
System Pressure ◽  
Model Size ◽  
Periodic Boundaries ◽  
Combustor Liner ◽  
Simulation Time

The main parts of the annular combustor liner walls of the Siemens gas turbine SGT-800 are convectively cooled using rib turbulated cooling. Due to the serial system of cooling and combustion air there is a potential of further reduction of total combustor pressure drop by improvements of the cooling system. Apart from the rib cooling, also the cooling channel bypass entrance is related to a significant part of the total cooling system pressure drop. In this study, an investigation is performed for a rib cooled channel which is related to the considered combustor liner and where empirical correlations are available in order to evaluate the methodology used. The study includes an assessment of the Reynolds Averaged Navier-Stokes (RANS) and Large Eddy Simulation (LES) models available within commercial Computational Fluid Dynamics (CFD) codes and includes also an investigation of model size when using periodic boundaries for LES simulations. It is well known that a small geometrical distance in the direction of the periodic boundaries may have a strong effect on the flow field but is often neglected in practice in order to speed up LES calculations. Here the effect is assessed in order to show what size is required for accurate results, both for time averaged and transient results. In addition too small domains may be affected by spurious low frequencies originating from the periodic boundaries requiring additional simulation time for time converged statistics, but also the averages may be significantly affected. In addition the simulation period for time converged statistics is evaluated in order to show that larger model size in the periodic direction does not necessarily require longer practical simulation time, due to the fact that larger volumes may be used for the combined time and space averaging. The aim is to obtain practical guidelines for LES calculations for internal cooling flows. Then the study is extended step by step to investigate the importance due to high Reynolds number, variable fluid properties and large temperature gradients in order to cover the ranges and specifics required for SGT-800 engine conditions.

Nucleation Processes in Large Scale Vapor Explosions

1979 ◽  
Vol 101 (2) ◽  
pp. 280-287 ◽  
Author(s):  
R. E. Henry ◽  
H. K. Fauske
Keyword(s):  
Large Scale ◽  
Interface Temperature ◽  
Liquid Droplets ◽  
Contact Interface ◽  
Vapor Cavity ◽  
Spontaneous Nucleation ◽  
System Pressure ◽  
Nucleation Model ◽  
Vapor Explosions ◽  
Cold Liquid

A spontaneous nucleation model is proposed for the mechanisms which lead to explosive boiling in the free contacting mode. The model considers that spontaneous nucleation cannot occur until the thermal boundary layer is sufficiently thick to support a critical size vapor cavity, and that significant bubble growth requires an established pressure gradient in the cold liquid. This results in a prediction that, for an interface temperature above the spontaneous nucleation limit, large cold liquid droplets will remain in film boiling due to coalescence of vapor nuclei, whereas smaller droplets will be captured by the hot liquid surface and rapidly vaporize, which agrees with the experimental observations. The model also predicts that explosions are eliminated by an elevated system pressure or a supercritical contact interface temperature, and this is also in agreement with experimental data.

L1 Adaptive Control for Aircraft Air Management System Pressure-Regulating Bleed Valve

2017 ◽  
Vol 139 (12) ◽  
Author(s):  
John Cooper ◽  
Chengyu Cao ◽  
Jiong Tang
Keyword(s):  
Management System ◽  
Control Valve ◽  
Pressure Control ◽  
Adaptive Controller ◽  
System Model ◽  
Flow Control Valve ◽  
L1 Adaptive Control ◽  
System Pressure ◽  
L1 Adaptive Controller ◽  
Linear Controllers

This paper presents an L1 adaptive controller for pressure control using an engine bleed valve in an aircraft air management system (AMS). The air management system is composed of two pressure-regulating bleed valves, a temperature control valve, a flow control valve, and a heat exchanger/precooler. Valve hysteresis due to backlash and dry friction is included in the system model. The nonlinearities involved in the system cause oscillations under linear controllers, which decrease component life. This paper is the unique in the consideration of these uncertainties for control design. This paper presents simulation results using the adaptive controller and compares them to those using a proportional–integral (PI) controller.

Development of a Thermal Stability Method for Phase Appearance and Disappearance Handling in Thermal Compositional Simulators

2021 ◽  
Author(s):  
Mohammad Reza Heidari ◽  
Terry Wayne Stone
Keyword(s):  
Thermal Stability ◽  
Mole Fraction ◽  
Phase State ◽  
Initial Guess ◽  
Real Field ◽  
Point System ◽  
Steam Flooding ◽  
System Pressure ◽  
Phase Saturation ◽  
Flash Calculation

Abstract Thermal compositional simulators rely heavily on multicomponent, multiphase flash calculations for a variety of reasons, including reservoir and wellbore initialization, phase appearance and disappearance, and property calculation. In a mass variable formulation, an isenthalpic flash is used for phase split computation, phase saturation update, component mole fraction update in different phases, and temperatures. A natural variable formulation utilizes an isothermal flash mainly for phase appearance and disappearance as well as computation of component mole fractions in appearing phases. Multiphase multicomponent isothermal flash calculations cannot be performed in narrow boiling systems which are very common in the simulation of thermal EOR operations such as Steam-Assisted Gravity Drainage (SAGD) or Steam Flooding (SF). In a narrow boiling point system, pressure and temperature are not linearly independent, and an isothermal flash will fail. In addition, flash calculations are computationally expensive, and reservoir simulators use different techniques to perform them as little as possible. A new thermal stability check has been developed that can be used in thermal compositional simulators and replaces an isothermal flash calculation. The new stability check quickly determines the phase state of a fluid sample and can be used as an initial guess for mole fraction of a phase appearing in the next simulation cycle. In this method, primary variables of the simulator are used as input for the stability check immediately after the nonlinear solver update so that computation of global mole fractions is not required. The new stability check can also be used in separator and isenthalpic flash calculations to determine the phase state of a fluid. An algorithm is provided, covering all different transitions of phase states in a thermal compositional simulator. The proposed algorithm is significantly faster than a flash calculation and saves simulation time spent in this calculation, hence the overall speed up is case dependent. The new stability check is simple, computationally inexpensive, and robust. It can be used for multicomponent and single-component systems, and we tested it rigorously against real field and synthetic models. The new thermal stability check always predicts the number of phase states correctly and never fails. In this paper, we demonstrate a thermal compositional simulation that is run without performing a single flash calculation.

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