In addition, after analysing the waste of steels, the writer also raises a better method of saving steels and reducing steel areas ratio by reducing hooping ratio.

This paper illustrated the architectural characters which related to smoke controlling,mainly introduce the parameters of atrium areas, ratio of length and width, figuration factor, leakage ratio, door-opening factor, window-opening factor, and dangerous exponent etc. Further researching needed to clarify the concrete relationship between smoke moving and architectural characters of atrium buildings.

Also, a dimensionless correlation for gas holdup involving superficial velocities of gas and liquid, cross sectional areas ratio, dispersion height to riser diameter ratio, as well as Froude and Morton numbers, was obtained.

The within-day RSD% for pseudouridine/ creatinine peak areas ratio was 3.4%.

In addition, LF to HF areas ratio (L/H) was computed.

The local corrosion was accelerated by the high cathode to anode surface areas ratio in vicinity to a preexisting microcrack edge.

The paper begins with a theoretical analysis of potential flow for the two-di- mensional conduit inlet,and after the boundary curve of constant pressure is obtained, it is transformed to the case of axial symmetry.It is hoped that the pressure along the new boundary,be nearly constant.The method of transformation is mainly that for equal distance ratios(i.e.,distance divided by entrance width in the two-dimen- sional case and that divided by entrance diameter in the axially symmetrical case), area ratios(i.e.sectional...

The paper begins with a theoretical analysis of potential flow for the two-di- mensional conduit inlet,and after the boundary curve of constant pressure is obtained, it is transformed to the case of axial symmetry.It is hoped that the pressure along the new boundary,be nearly constant.The method of transformation is mainly that for equal distance ratios(i.e.,distance divided by entrance width in the two-dimen- sional case and that divided by entrance diameter in the axially symmetrical case), area ratios(i.e.sectional area divided by entrance area in both cases)are equal. The pressure distribution along the curved wall of an axially symmetric inlet so obtained was calculated by the relaxation method,and that of another was measured from an air-flow model test.The results as given in Figures 10 and 13 of the paper show that although the pressure along the wall is not constant,the variation is not great.The paper finally suggests that as for to reduce the possibility of cavitation, the forms of the axially symmetric inlets given by Equations(5)and(6)of the paper may be considered as adequate for practical cngineering use,with the restriction that the value of k which appears in the two equations not be greater than 0.05,in order to prevent the possible separation of flow from the inlet wall.

文中给出了隧洞进水口曲线为等压的二元分析结果,然后将此二元进水口的曲线形式转变为轴对称进水口的曲面形式。所用的转变方法是:当 x/D=(x_1)/B时,d/D=(b/B)~(1/2),其中 d、x和 D 分别为轴对称进水口段中某断面的直径,由起始断面至该断面的距离和起始断面的直径;b、x 和 B 分别为相应二元情形的某断面的宽度,由起始断面至该断面的距离和起始断面的宽度。对用这种方法得到的一个轴对称进水口曲面上压力分布,进行了松弛法计算,还对另一个进行了气流模型试验。结果如文中图10及图13指明,曲面上压力虽然不是等值的,但变化不大。文中建议,就减蚀的意义而言,式(5)和式(6)所给轴对称进水口曲面的形式是可以考虑来作为实际工程上应用的,但为了避免可能发生水流从边壁上脱离的现象,式中 k 值应取小于或等于0.05。

Modulation of air stream is an efficient method of sound production. Man's speech organs, sirens, electro-pneumatic loudspeakers as well as common whistles are all based on this principle. The features of air stream sound sources are their high efficiency and possibility of high power outputs, which afford them practical value. The sound production by modulating air streams were discussed by previous authors and theories-given, but some were oversimplified and others too involved to allow practical computations....

Modulation of air stream is an efficient method of sound production. Man's speech organs, sirens, electro-pneumatic loudspeakers as well as common whistles are all based on this principle. The features of air stream sound sources are their high efficiency and possibility of high power outputs, which afford them practical value. The sound production by modulating air streams were discussed by previous authors and theories-given, but some were oversimplified and others too involved to allow practical computations. In this paper, air flow vs pressure characteristics of air stream sources are derived from the basic theory of gasdynamics and graphical method is presented for the estimation of sound radiation under given conditions of plenum pressure and nozzle-to-horn throat area ratio. It is established that although the air flow characteristics as well as the radiation relations are nonlinear, the radiated sound power is determined mainly by the radiation of the fundamental, and approximations give rise to simple expressions for the radiated sound power, the air stream yield and efficiency, with an error less than 1 dB from exact results. Charts are given to facilitate design and question of optimum condition is discussed.

Recently a JDC three bladed cpp series with expanded area ratio 0.35,0.50 and 0.65 was developed in the ship model towing tank of Shanghai Chiao-Tung University. The open water experimental results of the JDC 3-50 series are presented in this paper. All the experimental data are analyzed by the regression method in the DJS-6 digital computer. The polynomial coefficients, open water characteristic curves, Bp-δ digram and the hydrodynamical spindle torque curves are given. For practical design purposes a...

Recently a JDC three bladed cpp series with expanded area ratio 0.35,0.50 and 0.65 was developed in the ship model towing tank of Shanghai Chiao-Tung University. The open water experimental results of the JDC 3-50 series are presented in this paper. All the experimental data are analyzed by the regression method in the DJS-6 digital computer. The polynomial coefficients, open water characteristic curves, Bp-δ digram and the hydrodynamical spindle torque curves are given. For practical design purposes a simplified design chart and the calculated centrifugal spindle torque coefficients at the initial pitch ratios are also given.Compared with some foreign propeller series, it shows that the open water characteristics of the JUC 3-50 series are satisfactory.