The wastewater flow velocity in the channel immediately upstream of the screen will vary from 0.4 to 0.9 m s−1. What is the design headloss for the screens at the two extremes of flow? Assume that the friction coefficient is 0.84. A) What are the design head losses for the screens at the two extremes of flow (0.4 and 0.9 m/s) if the screen is mechanically-cleaned? B) What are the design head losses for the screens at the two extremes of flow (0.4 and 0.9 m/s) if the screen is manually-cleaned?

Amass of m 1.5 kg of steam is contained in a closed rigid container. initially the pressure and temperature of the steam are: p 1.5 mpa and t 240°c (superheated state), respectively. then the temperature drops to t2= 100°c as the result of heat transfer to the surroundings. determine: a) quality of the steam at the end of the process, b) heat transfer with the surroundings. for: p1.5 mpa and t 240°c: enthalpy of superheated vapour is 2900 kj/kg, specific volume of superheated vapour is 0. 1483 m/kg, while for t 100°c: enthalpy of saturated liquid water is 419kj/kg, specific volume of saturated liquid water is 0.001043m/kg, enthalpy of saturated vapour is 2676 kj/kg, specific volume of saturated vapour is 1.672 m/kg and pressure is 0.1 mpa.

The temperature of air decreases as it is compressed by an adiabatic compressor. a)- true b)- false

During a steady flow process, the change of energy with respect to time is zero. a)- true b)- false