Question

PROBLEM 2 (35 points). An insulated, rigid tank whose volume is 0.5 m3 is connected by a valve to a large vessel holding steam at 60 bar, and 440°C. The tank is initially evacuated. The valve is open only as long as required to fill the tank with stream to a pressure of 40 bar. As this occurs, a paddle wheel adds 260 kJ per kg of work to the tank (where the kg mass for this work represents the mass amount at the end of the process). Determine the final temperature of the steam in the tank, in °C and the final mass of the steam in the tank, in kg.

Answer 1

solution at Page: Date: Tank N20.5m3 vessel. pe uobar steam 8 260 kJ/kg- Go bar quoc Since this is free expansion process. for which work done by Steary will be reso, & Tank is rigid Const. volume) & Isolated, so No. Heat loss to surroundry. for mass of steam in Tamk ; : m = [sxv] = [1080x0.5] [ma 500 kg - Aug. & for free expansion, we know Tinitial = Tfinal when Nonong Energy 18 provided. so Itank will be 440¢ when No no paddle work is ponded,

Here total paddel work / Energy = (260 kJ) x 500 Wpaddle = 130mJ this work will increase the terms of steam from 440°c to Tf. so (130x106) a meu (dT) - 130x70%) = [s0 x 786] [76-6713] o. 440° c = 13K so Pp =(713 +330.79)x Pa 1043.79k or if = 770.79€ Aug