Jet Propellant Research Articles

Stabilization of Jointing Sand in Block Paving

This paper discusses the problem of loss of jointing sand in block paving, how to avoid attendant loss of interlock, and possible damage to the pavement structure from ingress of water. Reasons for the erosion of jointing sand so far identified are: (1) Action of jet blast and propeller wash from aircraft engines; (2) Use of vacuum sweepers for cleaning block‐paving areas; (3) turbulent water flow over pavement surface; and (4) degradation and pumping of laying‐course materials. Various materials have been used to try to stabilize the jointing sand; some have provided a temporary solution to the problem. However, the most effective means of preventing erosion problems has been found to be the use of a specially formulated liquid prepolymer that retains elasticity after curing and is thus able to sustain the essential flexible nature of the block‐paving system.

Design and Testing of a Water Tip Jet Propeller

This work was directed at the problem of developing a lightweight, low cost means of propelling a short run underwater vehicle. The system described occupies a position midway between the straight rocket and the geared turbine/propeller drive fed by a gas generator. It expands the propellant gases through a turbine, uses the turbine to direct drive a centrifugal sea water pump, and ejects the pumped water through jets at the blade tips of a specially designed propeller. Exhaust gas from the turbine is released from the propeller hub at the blade trailing edges. The reduction in turbine back pressure produced by the suction effect on the exhaust gas significantly increases turbine efficiency and reduces the system's sensitivity to operating depth. This paper covers the analytical design and sea testing of the water tip jet propeller and summarizes the test results. The test data, consisting of measurements of propulsive power vs tip jet flow rate and pressure at various vehicle speeds, indicate that the proposed system can provide specific power levels superior to those obtainable from any other underwater propulsion system for vehicles requiring a run time of about 3 s to 2 min. It has additional advantages of, relative insensitivity to depth, low cost, low self-noise, and absence of reaction torque.

Some British Research on the Basic Aerodynamics of Powered Lift Systems

Summary:The paper mainly discusses recent R.A.E. and N.P.L. research on the aerodynamics of Direct jet lift (turbo-jet and turbo-fan), Propeller lift (tilt-wing and deflected slipstream), Jet flaps, and Boundary layer control (blowing and suction). Some of the work at Firms and Universities is also mentioned where the information has been made available for general circulation. Attention is drawn to the present state of knowledge in relation to V.T.O.L. and S.T.O.L. aircraft applications and to some major aerodynamic problems which need further study.

JET PROPULSION ENGINES AND PROPELLER DRIVE GAS TURBINES—THEIR APPLICATION IN FUTURE AVIATION.*

Journal of the American Society for Naval EngineersVolume 58, Issue 4 p. 664-672 JET PROPULSION ENGINES AND PROPELLER DRIVE GAS TURBINES—THEIR APPLICATION IN FUTURE AVIATION.* R. P. Kroon, R. P. Kroon MANAGER OF ENGINEERING, WESTINGHOUSE AVIATION GAS TURBINE DIVISIONSearch for more papers by this author R. P. Kroon, R. P. Kroon MANAGER OF ENGINEERING, WESTINGHOUSE AVIATION GAS TURBINE DIVISIONSearch for more papers by this author First published: November 1946 https://doi.org/10.1111/j.1559-3584.1946.tb02719.x * Reproduced from the March 1946 issue of “the Journal of the Franklin Institute”. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume58, Issue4November 1946Pages 664-672 RelatedInformation