Target meters

In a target flowmeter, a target or impact plate is inserted into the flowing stream, and the resulting impact force is detected. The target meters are more expensive than orifices, but because they have no pressure taps to plug or freeze, they are better suited for applications where the process fluid is "sticky" or contains suspended solids. 

Wind Speed Temperature Gradient Terrain Description Position Spacing (meters) Distance Smoke Line from Target (Meters)... 

Not surprisingly, costs are several times higher than conventional wells. Nevertheless, overall project economics may favour ERD over other development options. For example, BP developed the offshore part of the Wytch Farm Oilfield (which is located under Poole Harbour in Dorset, UK) from an onshore location. The wells targeted the reservoir at a vertical depth of 1,500 meters with a lateral displacement of over 8,000 meters (Fig. 3.20). The alternative was to build a drilling location on an artificial island in Poole Bay. ERD probably saved a considerable amount of money and advanced first oil by several years. 

A method which competes with interferometric distance measurement is laser Doppler displacement. In this approach the Doppler shift of the beam reflected from a target is measured and integrated to obtain displacement. This method also is best suited to use indoors at distances no more than a few hundred meters. Table 2 compares some of the characteristics of these laser-based methods of distance measurement. 

The concrete block walls of the cell housing the generator tube and associated components are 1.7 meters thick. The facility also includes a Kaman Nuclear dual-axis rotator assembly for simultaneous transfer and irradiation of reference and unknown sample, and a dual Na iodide (Nal) scintillation detector system designed for simultaneous counting of activated samples. Automatic transfer of samples between load station to the rotator assembly in front of the target, and back to the count station, is accomplished pneumatically by means of two 1.2cm (i.d.) polyethylene tubes which loop down at both ends of the system and pass underneath the concrete shielding thru a pipe duct. Total one-way traverse distance for the samples is approx 9 meters. In performing quantitative analysis for a particular element by neutron activation, the usual approach is to compare the count rates of an unknown sample with that of a reference standard of known compn irradiated under identical conditions... 

In simulations, an area with dimensions 100 m. x 10 m. is secured by a WSN. The grid size is taken as one meter so that the detection probabilities of targets on adjacent grid points are independent. The... 

Figure 1. Transmitted power versus transmitted pulse length for X-band radar (30 dB antenna gain) — detection of ldBsm (1 square meter) target at distance 50 km.

A zoom-in view of the scene, figure 12, shows the area of interest (AOI) pixel locations and target locations. The targets were spaced so that they should be spatially resolved, based on the expected 25 meter resolution. 

The feed and melting sections upstream of the metering section are set using experience and existing experimental data. For example, if the base case worked well with a compression ratio and compression rate of 3.0 and 0.0035, respectively, then the target screw would be designed with the same upstream specifications. The compression ratio and compression rate are as follows ... 

As shown by the data In Table 9.3, the 80 mm diameter designed screw met the target performance and operated at essentially the predicted screw speed. The slightly higher screw speed that was used (58 rpm) was likely a result of the lower compression rate used for the 80 mm screw. The lower compression rate likely reduced the pressure at the entry to the metering section to a value less than 22 MPa. This lower entry pressure would cause the specific rate to decrease slightly and thus require the screw speed to Increase to produce the target rate. 

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