A one shell pass, one tube-pass heat exchanger, has counter flow configuration between the shell side and tube side fluids. The total number of tubes within the heat exchanger is $$10$$ and the tube dimensions are $$ID=10$$ $$mm,$$ $$OD=12$$ $$mm$$ and length $$=1m.$$ saturated dry steam enters the shell side at a flow rate of $$2$$ $$kg/s$$ and the temp of $${100^ \circ }C.$$ In the tube side, cold water enters at a flow rate of $$10$$ $$kg/s$$ with an inlet temp of $${25^ \circ }C.$$ The $$OHTC$$ based on the outer surface area of the tubes is $$50$$ $$W/{m^2}K.$$ The specific heat of water is $$4.18$$ $$kJ/kg$$-$$K$$ and the latent heat of steam is $$2500$$ $$kJ/kg.$$ What is the condition of the steam at the exit.

In shell and tube heat exchanger, baffles are mainly used to

An object has the shape of cubical box of side $$10cm,$$ with no top cover. The box is placed inside a room whose dimensions are much larger than those of the box. All the five surfaces of box are at a temp of $${500^ \circ }C$$ and have an emissivity of $$0.6.$$ The walls of the room are at $${25^ \circ }C$$ and have an emissivity of $$0.4.$$ All these surfaces can be assumed to be diffuse-gray. Find the net radiative heat loss from the inner surface of the box to the walls of the room.
Stephen Boltzmann constant $$5.67 \times {10^{ - 8}}\,\,W/{m^2}{K^4}$$. View factor between two parallel square plates placed directly opposite to each other is $$0.2$$

A diffuse radiation surface has