Nozzle optimization

H.G. Zhang. Research on Lance Nozzle Optimization of 120t Combined Blown Converter at Tonghua Steel Plant (Master thesis, Northeastern University, 2009), 5. 

Simple and sturdy construction of the exchangeable needles and nozzles Optimal thermal separation between hot and cold modules Uniform force application to all nozzles through the central hydraulic cylinder Reduced mould costs, since installation with different moulds is possible Easy matching of new moulds to the same cold runner head Cycle-time savings... 

A gas turbine used in aircraft must be capable of handling a wide span of fuel and air flows because the thmst output, or pressure, covers the range from idle to full-powered takeoff. To accommodate this degree of flexibiUty in the combustor, fuel nozzles are usually designed with two streams (primary and secondary flow) or with alternate tows of nozzles that turn on only when secondary flow (or full thmst power) is needed. It is more difficult to vary the air streams to match the different fuel flows and, as a consequence, a combustor optimized for cmise conditions (most of the aircraft s operation) operates less efficiently at idle and full thmst. 

The best designs provide for the percentage vaporization per pass to have been completed by the time the fluid mixture reaches the upper end of the tube and the mixture is leaving to enter the bottom chamber of the distillation column. In order to assist in accomplishing this, the initial reboiler elevation should be set to have the top tubesheet at the same level as the liquid in the column bottom section. A liquid-level control adjustment capability to raise or lower this bottoms level must exist to optimize the recirculation. Sometimes, the level in the bottom of the column may need to be 25-30% of the reboiler tube length above the elevation of the tubesheet. Therefore, the vapor nozzle return from the reboiler must enter at sufficient elevation to allow for this possibility. 

Factors Affecting Drilling Rates 1090. Selection of Weight on Bit, Rotary Speed, and Drilling Time 1091. Selection of Optimal Nozzle Size and Mud Flowrate 1097. 

Compute the pressure change inside the drillpipe at bottom when the pulse nozzle opens in each case. Give the optimal combinations for getting 200 to 250 psi pulses. 

Optimal hydraulics is the proper balance of hydraulic parameters (flowrate and equivalent nozzle size) that satisfy chosen criteria of optimization. Hydraulic quantities used to characterize jet bit performance include hydraulic horsepower, jet impact force, jet velocity, Reynolds number at the nozzle, generalized drilling rate or cost per foot drilled. While designing the hydraulic program the limitations due to cuttings transport in the annulus and pump performance characteristics must be included. 

On determining the optimal flowrate q (gal/min) and pressure drop across the bit nozzles p, the total flow area is calculated from... 

Methods of near-field, midfield and ensemble (global) imaging and real-time visualization have been developed for monitoring gas atomization of liquid metals.[327] The primary process sensors and monitors used include high-speed video and infrared imaging systems. The process monitors allowed continuous and detailed observations of the atomization process and enabled measurements of the key parameters necessary for adequate control and optimization of the process. The sensors provided the operators with real-time information on the temperature of nozzle tip, visual characteristics of atomization plume, and gas and metal flow rates. The images can be displayed in real time, offering the potential for more responsive process control. 

The experiments were carried out on a semi-industrial fluidized bed reactor, illustrated in Figure 9.6, which shows four different sensor positions (A, B, C and D). Screw fittings were used to mount the sensors in order to secure optimal sensor pickup efficiency. Sensor location A is mounted onto an orifice plate on the main supply line of liquid urea to the reactor nozzles, following Esbensen et al. [5]. The sensors B, C and D are located on the wall of reactor chambers 1, 2 and 4, respectively. 

An important open question relates to whether an optimal AR exists with regard to entrainment enhancement. Laboratory jet experiments with pseudo-elliptical geometries [27] suggest that an optimal AR with regard to nozzle-geometry-enhanced entrainment might be at a value AR = 3. However, the experiments are not conclusive since they involved AR up to 3.5 and nonuniform momentum-thickness distributions, which are known to also affect the entrainment process [5]. Moreover, the possible effects on jet entrainment of other more complicated interactions such as vortex-ring bifurcation still need to be established. 

There is opportunity in the future not only to perform CCD simulations to understand and develop parametrics of components, but also to elucidate inlet, combustor, nozzle interactions, and optimization. Further a validated system code is needed from the system performance prediction, comparison, optimization, and design points of view. The study should be extended to various fuel-oxidizer combinations. 

In order to overcome the difficulties associated with the non-choked fuel-flow system and the fixed fuel-flow system, a variable fuel-flow system is introduced the fuel gas produced in a gas generator is injected into a ramburner. The fuel-flow rate is controlled by a control valve attached to the choked nozzle according to the airflow rate induced into the ramburner. An optimized mixture ratio of fuel and air, which is dependent on the flight altitude and flight velocity, is obtained by modulating the combustion rate of the gas-generating pyrolant When a variable fuel-flow-rate system is attached to the choked nozzle of the gas generator, the fuel-flow rate is altered in order to obtain an optimized combustible gas in the ramburner. This class of ducted rockets is termed variable fuel-flow ducted rockets or VFDR . 

As the propane continues to thaw, the cold-stream should be brought closer to the sample. Optimally, the tip of the nozzle should be brought as close as possible to the sample without casting a shadow on the X-ray detector. 

In contrast to TSP interface, no extensive temperature optimization is needed with APCI. For systems providing a countercurrent drying gas, it is claimed that volatile as well as nonvolatile buffers can be used. Uncharged volatile material is swept away from the nozzle by the countercurrent drying gas, whereas nonvolatile contamination deposited in the source chamber can readily be wiped away without the need to switch off tire vacuum system. 

Binder concentration The optimal binder concentration will need to be determined for the formulation. If the binder is to be sprayed, the binder solution needs to be dilute enough so that it can be pumped through the spray nozzle. It should also be sufficiently concentrated to form granules without overwetting the materials. 

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