Shell and tube heat exchangers in energy plants and cogeneration
Wherever power is generated, heat is released - intentionally in a combined heat and power unit, as a loss in a standby genset, as the working fluid in a steam plant. In all three cases it has to move reliably from one circuit to another, usually between oil, water, glycol and steam. That is the home ground of the shell and tube design.
Typical duties
Engine and lubricating oil cooling in CHP units. The engine rejects part of its losses through the lubricating oil. The shell and tube heat exchanger cools it against the heating water circuit, so the heat stays in the system instead of leaving through an emergency cooler. The sizing works with the temperature-dependent viscosity of the oil.
Transferring hot water and steam. Waste heat boilers deliver hot water or saturated steam; both belong on the tube side of the high-temperature type. Steam condenses there in the tube coil and hands its latent heat to the shell-side circuit - a lot of duty from little steam.
Cooling water for gensets. Standby gensets, compressors and pump drives are connected to plant cooling water through a glycol-bearing intermediate circuit. The shell and tube heat exchanger separates the circuits so that the network’s pressure and dirt never reach the machine.
What matters in the sizing
With oil, the oil side governs the overall heat transfer; anyone calculating with water characteristics underestimates the area considerably. How that fits together is in the guide oil coolers with shell and tube units. With steam, the condensing side has no temperature change in the usual sense and its heat transfer depends on the condensate film; the calculation core has its own correlation for this, described in the guide heating with saturated steam.
The second point in cogeneration is the temperature level. High return temperatures in the heating water push oil and water close together, and every kelvin less of difference costs area. In the configurator’s live result you can see how the mean temperature difference changes with your temperatures.
Limits, stated honestly
The Shellcore configurator does not size exhaust gas or air sides; it sizes the heat exchanger between liquids and saturated steam. For exhaust gas heat exchangers and complete heat recovery packages, AWS-Technik GmbH as a whole is the right contact. Enter your operating point in the configurator - where the calculation model ends, our team takes over the sizing, and everything else is settled in the quote.
Frequently asked questions
Which oils does the configurator handle for engines and gensets?
Motor oil SAE 30 and hydraulic oil of classes ISO VG 22 and ISO VG 220. For any other oil, or outside the range shown, choose “Other medium” and name the grade, with fluid properties if known; the enquiry then goes to our engineers.
Can a shell and tube heat exchanger condense steam?
Yes. Saturated steam condenses in the tube coil of the high-temperature type and heats the shell-side circuit as it does so. The sizing needs the steam pressure, from which the saturation temperature follows, and the temperatures of the circuit to be heated; a condensate trap is part of every steam duty.
What about hot water and thermal oil?
Both belong on the tube side of the high-temperature types. Thermal oil is not in the calculation catalogue: choose “Other medium” in the configurator and name thermal oil, with fluid properties if known. Our engineers then size the unit with the matching fluid properties.
Request a sizing
Describe your application in the configurator - we will come back to you with an individual quote.