dear sir,
in CAESAR II there is no option to give flow direction ..since the temperature will flow in the direction of flow.. temperature will decrease as we go away from the equipment . how CAESAR II will take care of this point??

You need to place nodes at sensible positions along your pipe and input a series of reducing temperatures. Flow direction is not relevant to any calculation that CAESAR II does directly. Read the User Guide.

in calculating pipe stress within one line number, we usually assume it as uniform temperature and pressure. conservative? yes, but rather than you have to analyze the temperature decreasing in that single line number , which not make any significant result to the stress in pipe, you'd better compute it as a uniform temperature and pressure
or... you can fill out series of reducing temperature in every node, if you really really need it



regards