Comment on "Low-Area Ratio, Thrust-Augmenting Ejectors"

Several low-area-ratio jet pumps were evaluated experimentally in water. Principal geometrical variables investigated were area ratio, throat length, and nozzle spacing. Diffuser geometry was also varied, but to a lesser degree. Experimental values of efficiency and head ratio were compared to a one-dimensional theoretical prediction method previously found to be applicable to moderate and high-area-ratio pumps. Two related cavitation prediction parameters were developed and compared to experimental data.

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AREA-DELAY EFFICIENT FFT ARCHITECTURE USING PARALLEL PROCESSING AND NEW MEMORY SHARING TECHNIQUE

Journal of Circuits System and Computers ◽

10.1142/s021812661240018x ◽

2012 ◽

Vol 21 (06) ◽

pp. 1240018 ◽

Cited By ~ 5

Author(s):

YOUSRI OUERHANI ◽

MAHER JRIDI ◽

AYMAN ALFALOU

Keyword(s):

Parallel Processing ◽

Execution Time ◽

Area Ratio ◽

Experimental Results ◽

Ip Core ◽

Hardware Complexity ◽

Processing Elements ◽

Low Area ◽

Memory Sharing ◽

Delay Elements

In this paper we present a novel architecture for FFT implementation on FPGA. The proposed architecture based on radix-4 algorithm presents the advantage of a higher throughput and low area-delay product. In fact, the novelty consists on using a memory sharing and dividing technique along with parallel-in parallel-out Processing Elements (PE). The proposed architecture can perform N-point FFT using only 4/3N delay elements and involves a latency of N/4 cycles. Comparison in terms of hardware complexity and area-delay product with recent works presented in the literature and commercial IPs has been made to show the efficiency of the proposed design. Moreover, from the experimental results obtained from a FPGA prototype we find that the proposed design involves an execution time of 56% lower than that obtained with Xilinx IP core and an increase of 19% in the throughput by area ratio for 256-point FFT.

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Closure to “Discussion of ‘An Experimental Investigation of Several Low-Area-Ratio Water Jet Pumps’” (1970, ASME J. Basic Eng., 92, p. 20)

Journal of Basic Engineering ◽

10.1115/1.3424937 ◽

1970 ◽

Vol 92 (1) ◽

pp. 20-20

Author(s):

N. L. Sanger

Keyword(s):

Experimental Investigation ◽

Area Ratio ◽

Water Jet ◽

Low Area ◽

Jet Pumps

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Low-Area Ratio, Thrust-Augmenting Ejectors

Journal of Aircraft ◽

10.2514/3.58964 ◽

1972 ◽

Vol 9 (3) ◽

pp. 243-248 ◽

Cited By ~ 20

Author(s):

RICHARD B. FANCHER

Keyword(s):

Area Ratio ◽

Low Area

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Low Area Ratio Aircraft Fuel Jet-Pump Performances With and Without Cavitation

Journal of Fluids Engineering ◽

10.1115/1.2910077 ◽

1992 ◽

Vol 114 (4) ◽

pp. 626-631 ◽

Cited By ~ 11

Author(s):

M. Marini ◽

A. Massardo ◽

A. Satta ◽

M. Geraci

Keyword(s):

Prediction Method ◽

Area Ratio ◽

Flow Coefficient ◽

Low Flow ◽

Low Area ◽

Aircraft Fuel ◽

High Area ◽

Fuel Jet ◽

Jet Pumps ◽

Experimental Values

The experimental analysis performed on several small size low area ratio aircraft fuel jet pumps in JP4 is outlined. The variables investigated were area ratio, nozzle and throat diameters, nozzle and suction pressures. The experimental values of head ratio were compared to a one-dimensional theoretical prediction method previously found to be applicable to moderate and high area ratio pumps. The results show the necessity of making some modifications in the model at low flow coefficient values. Measured wall static pressures were also compared with the results of an axisymmetric finite difference turbulent calculation; the comparisons are generally in good agreement. The development of cavitation and related parameters were also investigated. In order to enhance cavitation resistance, which is particularly important in the field of aeronautics, some studies were carried out on two stage jet pumps. The results obtained are outlined and discussed.

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