Centerline velocity equation for the circular slot hood was thus constructed to design the local exhaust system. Recommended values for airflow rate into the circular slot hood and the average slot face velocity were found to be 20.14 m3/min and 8.55 m/sec, respectively. The optimum air velocity at a. InterestPrint Graphic Design Women's Long Sleeve Hoodie Mini Dress. 3.2 out of 5 stars 22. Related searches.
Sizing exhaust hoods - air volume flow and capture velocities - online exhaust hood calculator
Exhaust hoods are essential in kitchens, laboratories and industrial application for removing
- fumes
- mists
- vapors
- aerosols
- particulates
- hazardous substances
- polluting contaminants
Slot Hood Designs
before they 'escapes' to from the surrounding air.
In general for an exhaust hood to be efficient
- the height - y - should not exceed 1.20 m (4 ft)
- the distance - x - should not be less than 1/3 y
- the capture velocity - v1 - should not be less than 0.15 - 0.20 m/s (30 - 40 ft/min)
Note! Potential hazardous and polluting applications requires special solutions. Always check local regulations before design.
Capture velocity - v1 - for an exhaust hood can be estimated with the empirical equation
v1 = q / 2 y2 c (1)
where
v1 = capturing velocity (m/s)
q = air volume flow (m3/s)
y = distance between table and exhaust hood (m)
c = circumference of the hood (m)
(1) can be modified to calculate air volume flow
q = 2 v1 y2 c (1a)
Example - Kitchen Exhaust Hood
Slot Hood Design Studio
Required air volume flow for a exhaust hood with circumference 3 m located 1.2 m above a stove can be calculated as
q = 2 (0.2 m/s) (1.2 m2)2 (3 m)
= 1.7 m3/s
Note! The units don't match since the equation is empirical (a result of experiments).
Exhaust Hood Calculator
The air flow volume in the exhaust hood can be calculated below
Exhaust Hood with internal Plate
The efficiency of an exhaust hood can be improved by adding an internal plate.
The required air volume for an exhaust hood with an internal plate can in general be reduced to approximately 80% compared to an exhaust hood without a plate.
Exhaust Hood with Side Walls
The exhaust hood efficiency can be further improved by adding side walls.
Related Topics
- Ventilation - Systems for ventilation and air handling - air change rates, ducts and pressure drops, charts and diagrams and more
Related Documents
- Convective Air Flow from a Single Heat Source - Calculate the vertical air flow and air velocity generated by a single heat source
- Evacuation of Air - minimum Capture Velocities to avoid Pollution products transferred to the Room - Capture velocity to avoid pollution products from galvanic baths, spray painting boxes and more contaminating the surrounding room and environment
- Exhaust Outlets - Capturing Air Velocities - Capturing air velocity in front of an exhaust outlet - online exhaust outlet velocitycalculator
Tag Search
- en: exhaust hoods velocity air volume
- es: campanas de extracción de volumen de aire de velocidad
- de: Dunstabzugshauben Geschwindigkeitsluftvolumen
You’ll appreciate the solid construction and durable welded joints of our galvanized steel, stainless steel, aluminum and thermoplastic industrial ventilation hoods, each built to a specific size. A wide range of styles meets virtually any exhaust application—from vehicle maintenance to wastewater treatment to manufacturing. Single-piece construction is available up to any size that will fit on a truck and larger sizes are available in multiple sections for field assembly.
- Keep work environments free of harmful vapors, fumes, oils, particles and more
- Expertly designed with heavy-duty, high-quality materials
- Options and accessories offer customized design
Standard Construction
- 18-gauge galvanized steel
- 18-gauge 304 or 316 stainless steel
- .063' aluminum
- Thermoplastic materials (e.g. PVC, CPVC, PE and PP)
- Welded seams
KEY
Models
Other Information
- Installation and Maintenance Manual (PDF)
Options & Accessories
- Internal baffles
- Perimeter slot
- Double shell
- Dampered slot
- Side skirt
- Gutter and drain fitting
- Filter rack
- Mounted switch
- Light fixture
- Make-up air plenum
materials
- Galvanized steel
- 304 stainless steel
- 316 stainless steel
- Aluminum
- Polyvinyl Chloride (PVC)
- Chlorinated Polyvinyl Chloride (CPVC)
- Polyethylene (PE)
- Polypropylene (PP)
finishes
- Mill (Thermoplastic is only available in mill finish)
- Satin polish (only available in stainless steel)
- Prime coated
- Two-part polyurethane paint (standard and custom colors available)
- Other paint finishes available such as epoxy or phenolic resin
Paint finishes
Available in twelve standard colors as well as any custom color. Shown below are representations of the standard colors*.
*Colors shown are an approximation, each computer monitor displays color differently.
Application Information
For additional information regarding industrial hood applications refer to:
Industrial Ventilation Manual
American Conference of Governmental Industrial Hygienists
Cincinnati, OH 45211
513-742-2020
www.acgih.org
ASHRAE Handbooks
American Society of Heating, Refrigeration and Air Conditioning Engineers, Inc.
1791 Tullie Circle, N.E.
Atlanta, GA 30329
404-636-8400
www.ashrae.org
Customization
Custom hoods are available fabricated to customer supplied requirements. FAX or e-mail a sketch or drawing to KEES for quotation.
Some examples of custom fabricated hoods are:
- Backshelf hood with front extension and flexible curtains
- Backshelf hood with pad filter frames
- Barrel filling hood
- Conical overhead hood
- Downdraft table
- Equipment enclosure
- Melting furnace hood
- Spray booth