Ejector thrust augmentation for STOL aircraft applications

Streiff, H; Henderson, C.

doi:10.2514/6.1974-1192

Cited by 2 publications

(1 citation statement)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These are the ARL static tests, reported by Quinn, 7 in which hypermixing primary nozzles were used; static tests conducted by Ryan,8 in which struts containing microjets were employed, and the static and wind-tunnel tests reported by Streiff and Henderson. 9 These comparisons demonstrate the flexibility and accuracy of the computational procedure.…”

Section: Comparison With Experimental Datamentioning

confidence: 91%

Method for Analysis of V/STOL Aircraft Ejectors

Salter

1975

Journal of Aircraft

View full text Add to dashboard Cite

A digital computer program is described for aircraft ejector performance analyses. The effects on performance of temperature ratios, pressure ratios, specific-heat ratios, pressure losses, and aircraft forward speed are included. Momentum correction factors are computed within the program, and the method by which these are determined for rectangular ejectors with multiple nozzles is described. Theoretical and experimental results are compared for rectangular ejectors employing hypermixing nozzles and microjet nozzles. It is demonstrated that the predictions of thrust augmentation ratio are within 3% of the test data. The effects on performance of pressure ratio, temperature ratio, nozzle spacing, mixing section length, inlet and diffuser performances, and the degree of mixing achieved are presented. The analysis clearly demonstrates the importance of rapid mixing, and the role that the ARL hypermixing nozzle has played in advancing the state-of-the-art of aircraft ejectors. NomenclatureA = cross-sectional area b = jet half -width D h = mixing section hydraulic diameter / = friction factor h = mixing section width J =jet momentum Kj -inlet loss coefficient K m = momentum correction factor L -mixing section length m = mass flow rate N s = number of primary nozzles P = total pressure p = static pressure S 5 = nozzle spacing T = total temperature t = static temperature u = j et profile velocity An = excess velocity v = one-dimensional velocity x = distance downstream of nozzle exits y = distance normal to axis of symmetry 7 = specific heat ratio £ -velocity profile similarity parameter \f = nondimensional nozzle spacing T] D = diffuser efficiency p = density Subscripts oo = freestream 6 = primary stream conditions leaving the nozzles 1 = inlet 2 = secondary flow conditions in the nozzle exit plane 3 = diffuser entrance 4 = diffuser exit e = secondary streamwake velocity conditions

show abstract

Section: Comparison With Experimental Datamentioning

confidence: 91%