Optimum compression ratio

If there is no interstage cooling or if there is interstage cooling to a temperature other than 7), it can be shown that the optimum compression ratio for each stage (z) is related to the temperature entering that stage (7)) by... 

It is likely that optimum conpreasor station spacing, optimum compression ratio considerations, or fixed location of fields along the pipeline will dictate conpressor spacinga less than these distances It can be concluded that gas pipelines in the North Sea are unlikely to require a hydrocarbon dewpoint aj low as 32°F at 1000 psia. If it is not needed for operating reasons, it will not be in the best interest of the pipelines to specify a lower dewpoint. 

G. Materials of Construction. Evaporator materials of construction and their costs play a large role in determining the optimum compression ratio. Monel is a standard material of construction for brine evaporator bodies. Stabilized titanium (e.g.. Grade 12) is a frequent choice for heater tubing and Type 316 stainless steel for the circulating pumps. The evaporator normally will be of the forced-circulation type described in Section 9.3.3.2. It will either contain a number of effects or operate with vapor recompression. Salt-recovery centrifuges may be Monel or stainless steel. 

Fabrication. Acetal resins are most commonly fabricated by injection mol ding. A homogeneous melt is essential for optimum appearance and for performance of injection molded parts. A screw compression ratio of no less than 3 1 is advised and the size of the injection molded shot should be 50 to 75% of the rated capacity (based on polystyrene) of the barrel. 

Eor a considerable period, >90% of the new cars in Brazil operated on E96 fuel, or a mixture of 96% ethanol and 4% water (82). The engines have high compression ratios (ca 12 1) to utilize the high knock resistance of ethanol and deUver optimum fuel economy. In 1989 more than one-third of Brazil s 10 million automobiles operated on 96% ethanol/4% water fuel. The remainder ran on gasoline blends containing up to 20% ethanol (5). 

The gas turbine is operated at a compression ratio that maximizes the work produced per weight of air, as explained in the first reference. Your turbine is equivalent or similar to the W501G turbine described in the second reference. Its electrical power output is 230 MW, which fixes the size of your combined cycle. You are to configure a set of steam generators and steam turbines that provides the economic-optimum amount of electric power from the heat in the exhaust from the free turbine. 

Optimum screw speed is a function of the screw design characteristics (compression ratio and L/D ratio) as well as the rheological properties of the polymer involved. The melt temperatures of the higher-viscosity resins is particularly sensitive to changes in screw speed. 

Components such as engine mounts and bearing pads, must be clamped or otherwise compressed during bonding. A compression ratio of 5 to 10% based on the initial dimensions of the rubber component will give optimum bond performance. Compression must be maintained throughout the PV bonding cure cycle and until the bonded component assembly has cooled to below 50 °C, see Table 3.5. 

PERFORMANCE. Compressed helium for the experimental work was obtained from a standard ADL-Collins Helium Cryostat compressor system. The refrigeration load was measured by means of an electrical heater attached to the bottom of the displacer cylinder which is the coldest portion of the apparatus. Several speeds were studied in an attempt to determine optimum operating conditions. The most Complete tests were carried out with a large compression ratio (p=200 psig, Pq psig). although several other values of p and pq were also studied. 

Compression nUxo (r, dimensionless) An initial estimate of compression ratio should be guessed. Once the preliminaiy optimum line size is estimated, compression ratio should be updated. It only considers line pressure drop, using the starting point pressure as suction pressure, and suction pressure plus line pressure drop a discharge pressure . See section IV,3 (2) for more comment... 

An example of an application of CAO is its use in optimising the distribution of gas in a gas lift system (Fig. 11.3). Each well will have a particular optimum gas-liquid ratio (GLR), which would maximise the oil production from that well. A CAO system may be used to determine the optimum distribution of a fixed amount of compressed gas between the gas lifted wells, with the objective of maximising the overall oil production from the field. Measurement of the production rate of each well and its producing GOR (using the test separator) provides a CAO system with the information to calculate the optimum gas lift gas required by each well, and then distributes the available gas lift gas (a limited resource) between the producing wells. 

The Intercooled Regenerative Reheat Cycle The Carnot cycle is the optimum cycle between two temperatures, and all cycles try to approach this optimum. Maximum thermal efficiency is achieved by approaching the isothermal compression and expansion of the Carnot cycle or by intercoohng in compression and reheating in the expansion process. The intercooled regenerative reheat cycle approaches this optimum cycle in a practical fashion. This cycle achieves the maximum efficiency and work output of any of the cycles described to this point. With the insertion of an intercooler in the compressor, the pressure ratio for maximum efficiency moves to a much higher ratio, as indicated in Fig. 29-36. 

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