1.What are the important parts of thermal power plant?- BOILER – FURNACE - TURBINE - HEAT EXCHANGER - COOLING TOWER

2.What is meant by heat transfer process? Write its 3 types.- Transfer of heat from one place to another place, Which occurs as a result of a temperature difference- Conduction - Convection - Radiation.

3. Write any 2 important differences between conduction and convection.* Conduction- Heat transfer in bodies due to fixed molecules. - This take place is solid bodies.* Convection- Heat transfer in bodies due to moving molecules. - This take place in flawed liquid of gas

4.Write Fourier law of heat conduction and explain the terms in it.- q conduction = -kA x (∆T /∆ x )where A the cross- sectional area. ∆T temperature difference ( T1-T2) between the two surfaces separated by a distance Δx

5.What is meant by natural convection heat transfer process?- is the heat transfer process where the heat transfer takes place due to the natural temperature difference or density difference and no external forces are employed for the fluid movement.

6.Write and explain the terms in the formula for calculating the radiation heat transfer process ( Name the law )- q emitted = εσ . AT4where A is the surface area, T is the temperature of the body, σ is a constant called Stefan-Boltzmann constant, equal to 5.67×10-8 W/m2K4, and ε is a material property called emissivity. The emissivity has a value between zero and 1.

7. Write briefly about a) Laminar flow b) Turbulent flow c) Parallel flow c) Counter flow.- Laminar flow: which the fluid particles move in regular path. - Turbulent flow: is the one in which the fluid particles move in zig-zig path- Parallel flow: is the one where the 2 fluid steams move parallel to each other.- Counter flow: the one where the fluid steams move opposite to each other.

8. Name the various types of heat exchangers.- Parallel flow heat exchanger. - Recuperation heat exchanger. - Plate heat exchanger. - Counter flow- Regenerative - Shell& tube heat exchanger. - Cross flow heat exchanger. - Direct& indirect contact- Double pipe heat exchanger

9.Write the expansion of LMTD.- Log-mean temperature difference (ΔTlm )

10. Write the 2 limitations of Plate heat exchangers.- Plate exchangers are limited when high pressures, high temperatures, or aggressive fluids are present.- Because of this problem these type of heat exchangers have only been used in small, low pressure applications such as on oil coolers for engines.

11. Write 4 important parts of a shell and tube heat exchanger.- Shell - tubes - rear header - front header – baffles - tubes sheet

1. What does ASME stand for, and do I need it for my installation? How does it differ from UL?

J: American Society of Mechanical Engineers (www.asme.org). ASME is a global design standard. In order for a product to be ASME certified, it must be designed and fabricated in accordance with the universally accepted ASME guidelines. UL, on the other hand, is an independent third party testing and certifying body (www.ul.com) . Now, whether or not your installation requires ASME is a question that you have to answer. Sorry buddy, we can’t help you here. You should verify with your local plumbing codes and legislations in regards to what certification is required. Rule of thumb is that majority of the institutional, commercial, and industrial installations require it, but it would also depend on the size of the unit, what the heat exchanger is suppose to do, the market you’re in, etc. At times it’s not required, but someone just wants to make your life difficult and put it in the specs anyways!

2. What information do I need to size a heat exchanger?

J: Look at your hand. Five fingers, five parameters. A heat exchanger…exchanges heat. Didn’t see that one coming, huh? This means that whatever you want to get out of the exchanger depends on what you put into it. There are two sides to the equation, the HOT side, and the COLD side. So, for each side, what are your fluids, what are your inlet and outlet temperatures, what are your flowrates, what BTU do you need? Give us five numbers, and we’ll give you a heat exchanger. Now, if five is too much to handle, give us what you have, and we’ll work with you to determine the rest.

3. Why can’t I use stainless steel for salt water pool applications?

J: Answer is simple. The salt in your pool will corrode the stainless steel. Don’t take our word for it, just google the question and see. It doesn’t matter who the manufacturer is, we’re talking about basic metallurgical properties. We didn’t make it up, trust me. If you want something to last in your salt pool and not look like old swiss cheese after a few seasons, try one of our products that are designed specifically for this purpose. Materials available are titanium and marine grade (Nicrom 24).

4. Do I need to clean my heat exchanger?

J: Do you need to clean your heat exchanger??? How much did you spend on the thing? Don’t you want to prolong its life, make sure it’s unclogged and free of buildup, get rid of any nasty residue in the cracks? You clean your car, you clean your shoes, so yeah, clean your heat exchanger. And if you tell me that the unit has water in it all the time anyways, so why bother cleaning, I’m going to throw a shoe at you. On to the next question…

5. How do I know if I need a plate or tubular heat exchanger?

J: Good question, mate. Sometimes if you go to a manufacturer that only makes one type or the other, they’re going to push their product on you, regardless. So let me give you a straight answer. Your application parameters will typically dictate which design is more effective for the job. Not to say that the other one won’t work, it just won’t work as well. You might end up with something double the size, and price. Now, if you’re the type that thinks everything in life is fair and equal, and for some applications it is, then it simply comes down to a matter of taste (like, Molson or Labatt). Remember to take into consideration some of your other requirements too (space constraints, budget, availability, materials of construction, etc.).