For the sizing problem:

The main basic Heat Exchanger equation is:

1. Q = U x A x ΔTm = The log mean temperature difference ΔTm is:
2. ΔTm = (T1 – t2) – (T2 – t1)
3. = °F. Where:
4. T1 = Inlet tube side fluid temperature; t2 = Outlet shell side fluid temperature;
5. ln (T1 – t2) (T2 – t1)

Plate exchanger is the most efficient due to turbulent flow on both sides. High heat-transfer coefficient and high turbulence due to even flow distribution are important. However, a plate heat exchanger regenerator is restricted to low viscosities. With high viscosities, a special tubular may be required.

1. Calculate the effectiveness.
2. Calculate the capacity rate ratio.
3. Calculate the overall heat transfer coefficient.
4. Determine NTU.
5. Calculate the heat transfer surface area.
6. Calculate the length of the tube or heat exchanger.

Thermal design of a shell and tube heat exchanger typically includes the determination of heat transfer area, number of tubes, tube length and diameter, tube layout, number of shell and tube passes, type of heat exchanger (fixed tube sheet, removable tube bundle etc), tube pitch, number of baffles, its type and size.

Heat exchangers are classified according to transfer processes into indirect- and direct- contact types. FIGURE 1.2 (a) Classification according to process function; (b) classification of condensers; (c) classification of liquid-to-vapor phase-change exchangers.

copper

0.99 385.0

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A true “brick wall” would consist of at LEAST three layers (“wythes”) of 3-5/8″ brick, for a total nominal thickness of 12 inches. That would be enough to stop pretty much any handgun round, and at least a few rounds from almost any rifle out there.