# Tag Info

• 2,135

### estimating the surface area of a steam coil immersed in a tank

One thing to consider is that pipes used for heating like this are normally « finned » to increase the surface area - fins can be small discs fitted to the pipe or even wire loops - both increase the ...
• 13.9k

### Energy required to raise temperature of water flowing through a heater

10 litres per hour 10 kg per hour 10,000 g per hour 166.66 g per minute 2.77 g per second Every second, you need to raise the temperature of 2.77 g of water by 30 °C. 2.77 g of water 4.18 J/g ...
• 131
Accepted

### Log Mean Temperature Difference of a Counterflow Heat Exchanger

$\triangle max$ and $\triangle min$ are not defined as maximum and minimum temperature differences in a heat exchanger. Quoting from Wikipedia: The LMTD is a logarithmic average of the temperature ...
• 2,149

### Most efficient heat exchanger for dirty air/water medium?

I'm going to have to make this an answer. If someone feels it's inappropriate I can delete it, what follows is the start of my comment. Grin, I bought my house with an outdoor wood stove, we have ...

### Valve first,then heat exchanger OR heat exchanger first then valve

I think the key information is that the liquid is saturated. This means any reduction in pressure will lead to partial vaporization and two phase flow. For heat tranfer best overall heat transfer ...
• 121

### why not put the compressor right next to the evaporator?

The evaporator is usually in the area to be cooled ie where the people work, read etc As the compressor takes space and tends to be noisy it is located away from that area. That makes the system in ...
• 13.9k

### What is the fouling effect (in rate, foulant thickness) of sand inside tube side of a shell and tube heat exchanger?

There is quite a bit to unpack here, so I may need to deconstruct your question a bit. Your question is surrounding the fouling rate of a Shell & Tube (S&T) heat exchanger which I will get to, ...
• 605

### In a shell and tube heat exchanger, does reducing flowrate affect the outlet temperatures?

I assume you are referring to a exchanger like the following: If : the external dimensions of the heat exchanger remain the same. the tubing diameter remains the same. the number of tubes changes (...
• 22.6k

### Why does thermal conductivity of a pipe matter in a double pipe heat exchanger?

In the steady-state case you describe, the thermal conductivity determines how much heat (kW) a material will trasnmit per unit surface for a given temperature difference (K). In heat exchanger ...
• 4,618

### Cooling system to maintain 0.5 °C at 95% humidity

At near-freezing temperatures, the amount of water vapor in the air to get 95% relative humidity is tiny, this is no problem. I recommend filling 55 gallon poly drums on pallets with water, park them ...
Accepted

### Does it make sense to increase the thermal "dead weight" of a wood stove?

Several high performance houses with lots of insulation have been designed with wood stoves that are surrounded by lots of stone to give the thermal mass. Some are still giving out heat 24 hours after ...
• 13.9k
Accepted

### Most efficient heat exchanger for dirty air/water medium?

I can't speak from real (=hands on with my own hands) experience, but in industrial applications I see mostly shell and tube type HX. Exhaust is in the tubes, the shell has the water. Pros: lots of ...
• 4,618

### Optimizing return temperature in a brazed plate heat exchanger

As stated the problem is probably not well enough constrained. Given the specification, the way you get minimum temperature out is to pump as much volume as you can through the primary and then ...
• 3,824
Accepted

### How to size a heat exchanger for a shear thinning fluid?

First, as Arthur notes, even the best Nusselt number correlations are often as much as 20% off, so don't expect any analytical method to give results that are much better than approximate. With that ...
• 1,167

### Can I use a pipe of any material other than copper in a counter-flow heat exchanger?

No, not any material. Only materials with a higher thermal conductivity than copper will increase the rate of heat transfer. In some cases, you may get better heat transfer by using a stronger ...
• 2,989

Either your definition of "completely" is a bit unusual, or there's something wrong with those charts, because in those charts, 1.6 x the model does not completely match any of the six observations ...
• 3,701

### Heat Exchanger Design - finding necessary variables

Between 135 F and 100 F I don't think the heat capacity or density would vary much so using average properties should be fine. If you want to be more conservative you can use the higher Cp between ...

### Fluid allocation for shell and tube heat exchanger

This is a good start for your decision and you can probably get away with it however you should factor in everything that influences that decision. Cleaning Corrosion Fouling Temperature Viscosity ...
• 1,704

### Radiators in series or parallel?

Assumptions: "Radiator" means a forced-air air-to-fluid heat exchanger. Radiators in either setup will pull from their own fresh air source (not from the exhaust of another radiator). Ignoring ...
• 7,469

### Process fluid flow in a fired heater

It is just getting as much heat as possible. Heat flows from hot to cold. The convection section is a much lower temperature. The convection section is basically waste heat in flue gas. The cold ...
• 479
Full Analysis Perfectly Insulated System The best case is to analyze this system in both the time and position domains. The time domain considers the variation of the reactor temperature $T_r(t)$ ...