What makes a steam boiler a closed system?

Most of the literature on shell and tube heat exchangers presenting the heat transfer coefficient correlations does not specify if there are any differences when dealing with vertical and horizontal orientations. Would the differences be only in terms of the shell-side fluid velocity ( and consequently Re) but the correlations would remain the same? How do these differences in orientation play out in the design?

i am doing a study related to axial compression on mild steel .i need coefficient of friction value when mild steel tube axially compressed by a large mild steel projectile.i am using abaqus FE software

Homogeneity of a mixture depends on the miscibility of components, on their diffusion and on their chemical compatibility (whatever the field of use). What kind of parameters must I take in account to understand this miscibility? What tools exist to predict the miscibility of 2 liquids?

In sub-critical thermal power cycle, the thermodynamic fluid absorbs certain amount of latent heat during phase change from water to steam but in a super critical unit, this absorption is zero. Now question is, how much this factor helps in improving the cycle efficiency of a super critical thermal power cycle?

Practising Efficiency engineers in large thermal power plants can answer this question.

A current steam generator delivers to the stack flue-gases at 200-220 degrees Celsius. Do you know possible ORC applications in operation that recover such low potential waste heat?

The fluid should not be water and should be cheap. Basically it should gain and dissipate heat with great efficiency i.e. Cp value should be high and K value low.

Dear Sirs/Madams,

i have heat box and V of this heat box is 66.571m^3. and temp in this room is 80 degree. how long does it take time if i want to heat 180drums in there.

as you can see inside of heat box, there is 2 layers and each layers has 80drums(4 x 10). 

if density of oil is 0.896, specific heat capacity is 2000, and temp of oil is 15degree, how long does it take time to heat the drums(in center. i think drum in center should take longer than any other drums) from 15 degree to 80 degree. i know this is kind of complicate. can anyone have any fomula that i need to use and any help would be really great. ps: dirty and simple calculation should be fine too.

best regards,