Engineering Stack Exchange
Engineering Stack Exchange

Questions tagged [airflow]

233 questions
3
votes
2 answers

How to calculate the required airflow to dry a batch of sawdust?

Sawdust has to be dried while in storage waiting to be processed. The time window for the drying is 12 to 36 hours. The storage room is 20m x 20m x7m (L x W x H). The sawdust is stored on 300m2 of the 400m2 available. It is placed on tent vented…
recyclestuff
  • 31
  • 2
2
votes
2 answers

Which fan / blower type should I chose?

Goal I am creating a project where I will need to move small beans around in turbulent air flow. I will have a heat source to which I do not want the heat to leave easily (I want the beans to be allowed to heat up). I initially tried to purchase a…
Eric F
  • 205
  • 1
  • 6
1
vote
1 answer

How do I convert cubic metres/feet per minute to a pounds per hour flow rate?

I am checking the leak rate of a carbon seal installed on an aircraft engine bearing. The test cart has a reading of pounds per hour but my manual says the leakage should not be more than 0.08 cubic metres (2.5 cubic feet) per minute of free…
godfrey
  • 13
  • 4
1
vote
1 answer

Wind protection for solar installation

A previous question here was relating wind deflection to drag creation in vehicle solar panel installations. In a residential installation drag is not the issue, but uplift is a critical concern. Since the efficiency of solar panels is affected by…
Mark
  • 11
  • 1
1
vote
1 answer

How to Convert between Air (Dry Air) Normal Liters per Minute (NLPM) and Pounds per Minute (PPM)?

I need to check the leakage of a product, the requirement is basically need to place a flow meter between dry air supply and the product, and apply a pressure of 100, 200, or 400 PSI, and ensure the flow rate reading on the flowmeter is less than…
AAM
  • 11
  • 2
1
vote
2 answers

Noise in centrifugal fan

I'm currently designing my own centrifugal fan for one of my projects, everything excluding the motor. My design is similar to the above just that the outlet is much shorter. The problem I'm facing is that my fan produces a high pitch noise.…
Wb10
  • 45
  • 2
1
vote
0 answers

What's inside a peak expiratory flow meter, and what's the difference with an anemometer?

The peak expiratory flow meter is usually used to manage asthma. I wonder what's inside it and how can it measure peak flow? What's the difference between this and an anemometer? Can an anemometer be used to do this work? Or is there something…
Mechanical Engineering
  • 11
  • 2
0
votes
1 answer

Air flow dissipation rate

Consider two streams of air flowing through the nozzles to an unlimited volume with atmospheric pressure. The flow is the same, but the cross section areas of the circular nozzles and the speeds differ, so the flow through the smaller nozzle is…
George Polevoy
  • 133
  • 6
0
votes
2 answers

Vacuum cleaner hose length & diameter vs air resistance

I have 1600 Watt vacuum cleaner, I need to use 32 ft of hose (10 meters), I have a choice here, whether I buy a hose with diameter 3 inches (75 mm) or 2 inch (50 mm) or 1 inch (25 mm). Which hose diameter will provide less resistance, better airflow…
LilBro
  • 101
0
votes
2 answers

Airflow theory in wing design

In a race car rear wing with 2 airfoils, why does the second airfoil have a greater angle of attack compared to the leading airfoil? Also, what is the best offset distance between the 2 airfoils in a racing car rear wing?
user36483
  • 25
  • 5
0
votes
1 answer

How much cm needed for airflow? - optimal window shutter distance

I am thinking that air (if it is still) is a very good insulator. So why aren't we putting the window shutter far away from the window? It would have more air between the window and the shutter and the Question: it would cause better insulation?…
KollarA
  • 11
  • 2
0
votes
1 answer

Why do different air compressors have different flow rates?

I bought a little compressor that does 2.6 SCFM at 90 PSI. But I have a tool that needs 10 SCFM at 90 PSI. If you imagine PSI as voltage, and flow rate as amperage, then it might follow that the only thing limiting the flow rate is resistance. If…
toyahs
  • 11
-2
votes
2 answers

Doesn't this fan spin the wrong way?

I have a fan on a stand, to circulate air in my home. The three fab blades are somewhat "D"-shaped, with one edge being rounded and one being straight-ish or even curving inward. Now, from my sailing, as well as my understanding of wing and…
KlaymenDK
  • 241
  • 2
  • 8