232 posts
TimePosted 28/10/2011 07:19:45
xxxx says

### FLOW CALCULATION AT BLOWER INLET

I HAVE A ROOT BLOWER .

I MEASURE VELOCITY AT BLOWER INLET ( BEFORE FILTER) OF SIZE 20 INCH x 20 INCH SQUARE.

THE INLET SQUARE IS FITTED WITH A FILTER OF 50 MIC.

HOW CAN I CALCULATE THE USEFUL AREA FOR FLOW CALCULATION BY VELOCITY MEASUREMENT?

IF I AM NOT WRONG IT SHOULD BE

VELOCITY X 20X20X0.96

WHERE 96% IS THE FILTER EFFICIENCY

BUT

ACTUAL AREA OF FLOW IS NOT 20X20 I THINK I SHOULD SUBTRACT THE AREA BLOCKED BY THE FILTER MESH.

I DO NOT HAVE THICKNESS OF THE FILTER MESH WIRE

XXXXXXXXXX

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36 posts
TimePosted 27/07/2012 07:25:27
BLM says

### re FLOW CALCULATION AT BLOWER INLET

Dear sir,

Filter efficiency neednot required to consider while calculating flow because what ever velocity you are getting by animo meter is net velocity just you can apply the area to get the flow. while taking the velocity with animo meter just you have to take care that there should not be influency of ambient air velocity.

BLM

19 posts
TimePosted 10/09/2012 03:06:28
Engr says

### re FLOW CALCULATION AT BLOWER INLET

Dear bro, u not need to take any consideration for the filter as it has no any connection with vol flow calcuation. What i suggest is to take velocity at inlet and multiply by the area ie 20*20. One thing u have to take care is that velocity should be taken with care as the volocity is max at centre so u have 2 solutions for taking Avg velocity No1 Vavg = 0.85 vmax No2 Take velocity at 5 different points and make an avg of it. U r done.

77 posts
TimePosted 11/09/2012 07:19:59
Vikpro says

### re FLOW CALCULATION AT BLOWER INLET

Dear All,

If you are measuring velocity @ suction area ( before grill) than you have to minus grill size in flow calculation, if flow is measurement after fan than no need.

Vikpro