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The propeller is the predominant propulsion device used in ships. The performance of propeller is conventionally represented in terms of non-dimensional coefficients, i.e., thrust coefficient (K T ), torque coefficient (K Q ) and efficiency and their variation with advance coefficients (J). It is difficult to determine the characteristics of a full-size propeller in open water by varying the speed of the advance and the revolution rate over a range and measuring the thrust and torque of the propeller. Therefore, recourse is made to experiments with models of the propeller and the ship in which the thrust and torque of the model propeller can be conveniently measured over a range of speed of advance and revolution rate.Experiments are very expensive and time consuming, so the present paper deals with a complete computational solution for the flow using Fluent 6.3 software. When the operating pressure was lowered below the vapor pressure of surrounding liquid it simulates cavitating condition. In the present work, Fluent 6.3 software is also used to solve advanced phenomena like cavitation of propeller. The simulation results of cavitation and open water characteristics of propeller are compared with experimental predictions, as obtained from literature [1].

Euphorbia telanganensis (Euphorbiaceae), a new species is described and illustrated from dry deciduous forest of Amrabad Tiger Reserve, the Eastern Ghats of Telangana state. The present new species is similar to Euphorbia jodhpurensis but differs in obovate or elliptic-obovate or ovate-elliptic, abaxillay pubescent leaves, 1.5–2.2 mm long peduncle, turbinate involucre, ellipsoid glands, unequal gland limbs, shallowly undulate posterior limbs, capsules deeply keeled, and trigonous.

Centrifugal fans usually operate at high rotating speeds and hence generate high levels of noise whose reduction over a broad range of operating conditions is a key concern for the designer. An important first step in this direction is identification of noise sources and its quantification. For this purpose, Computational Fluid Dynamics (CFD) and computational aeroacoustic analyses is performed on centrifugal fans with backward impeller, radial impeller and forward impellers using CFD code FLUENT. To validate these results noise measurements are performed on centrifugal fans with backward impeller, radial impeller and forward impellers. The results so obtained from numerical analyses are compared with the measurement results. It is found that there is good agreement between numerical and experimental results. From these results it is observed that least noise of 92.6 dB(A) and high flow rate of 0.399 m 3 /sec occurs with backward impeller whereas large noise of 102.5 dB(A) and least discharge of 0.365 m 3 /sec is observed with forward impeller. The present study concludes that backward impeller radiates less noise and high discharge compared to radial and forward impellers.

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