2. Compare the heat loss in W from two windows of a room, one having a single sheet of glass 4 mm thick while the other has two sheets of glass, 2 mm thick each, separated by 2 mm of air. The second window is called a thermopane. The window sizes are 1.5 m × 2 m. The air temperature in the room is 23°C and the outside temperature is -10°C. The average value of the thermal conductivity of glass is 0.96 W/m·K and that of air is 0.0257 W/m·K over this temperature range of interest. The heat transfer coefficient corresponding to slower moving air inside the room is 5 W/m2·K and that of the faster moving air outside is 25 W/m2·K. Consider the thin layer of air between the glass sheets to be stagnant.

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.

Condition monitoring is a major component of. (clo4) a)- predictive maintenance. b)-preventive maintenance c)-proactive maintenance d)-reactive maintenance.

Hydraulic fluid with a sg. of 0.78 is flowing through a 1.5 in. i.d. pipe at 58 gal/min. the fluid has an absolute viscosity of 11.8 x 105 lbf-sec/ft2. is the flow laminar, turbulent or within the critical range? give both a numerical reynolds number and a term answer.