Recent content by sanka

The equation Q=mCpdeltaT will give you the energy lost from the water. This will be in Joules or kJ. If you can record the time it takes the mass of water to reach ambient temp, divide Q by this time to get the rate of energy lost. Units will be Joules/seconds to give Watts. Regarding the...

The way I've always defined a "fin" is that it is a geometrical extension/additional area to the primary surface. So as a classic example think of heat sink in computer. The main/primary surface is the heat sink base, which is fixed to the CPU/GPU, whatever the heat dissipating element is...

Thanks a lot for your response Chet, I appreciate it. For the most part I understand everything you said. However, one thing is still bothering me and I have highlighted it in the quotation above. You say the temperature at the wall is lower than the temperature at the interface, which of...

I'm having a bit of difficulty conceptually understanding a problem. Hoping someone here can clear it up for me. In a simple circular condenser tube (which is cooled by water or air) what happens the tube wall temperature as the steam inside is condensed? Intuitively I would have thought that...

As russ has just pointed out, increasing the air flow rate doesn't necessarily increase the "heat transfer rate". This is a common misconception. The heat to be removed from a CPU is a function of the CPU's operating condition. For example, for a CPU operating at nominal load the heat...

Hi ericksonla, this topic is of interest to me. Presently, I am preparing to carry-out some experiments with low pressure steam in a lab-scale air-cooled condenser. I have the option of using a liquid ring vacuum pump or a rotary vane vacuum pump. I am not sure which one is more suitable so I...

For anything related to heat exchangers, I would recommend the book "Fundamentals of Heat Exchanger Design" by Ramesh K. Shah and Dusan P. Sekulic. I've found it to be an excellent source for theory, analytical solutions, empirical correlations, etc. related to all kinds of heat exchangers...

Just a thought, but what is the pressure drop across the larger heat exchanger? If this is bigger than the pressure drop of the smaller heat exchanger, it will mean that the flow rate through the larger heat exchanger will be less - provided that the fan speed remains constant for both cases...

In reality, in a Rankine cycle, steam isn't compressed due to the fact that it requires quite a lot of energy to "pump" a compressible gas such as steam to a higher pressure. In reality, the steam is condensed to water condensate which is subsequently pumped up to the boilers working pressure...

There are a lot of very good heat transfer books out there. Opinions tend to differ on which is best, all down to a matter of preference I suppose. If your looking for a sort of introduction to the topic I would suggest "Heat Transfer" by Holamn. Good explanations of the various physical...

I haven't looked at your values in any great detail but the characteristics you are seeing in your measurements are to be expected. You are on the right track when you say that "its due to the fact that the air mass flow rate has increased therefore the air stays in "one" place for less time so...

Maybe I'm over-analysing this but if we take a simple example of a tube within which steam is flowing. Why does the temperature (and pressure) of the steam increase as the mass flow rate is increased? Is it simply because as more mass is added in the flow, the pressure within the system...

You need to provide a bit more detail about the specific problem. Suppose you are referring to condensation which is essentially isothermal heat rejection. So if you know the inital value of h (from an assumption of isentropic expansion through the turbine, for example), the final value of h...

Unless you are doing a very specific analysis which requires a good degree of accuracy, you can almost always neglect the work done by the pump. If you are unsure why, I'd recommend that you calculate the work term and compare it to the heat added and rejected by the boiler and condenser...

Similar to the answer given by rock.freak667, the parameters usually measured are temperature, pressure and flow rate. Most properties (such as enthalpy, entropy, etc.) are simply functions of the steam temperature. One important point to add is that the steam quality (dryness fraction) is an...