The airflow requirement depends on the acceptable temperature rise as air traverses through the computer unit. For air inlet temperature of 55 deg. F and a temperature rise of 20 deg. F, the required cooling airflow rate (CFM) can be calculated as:

There is a great deal of confusing and misleading information being circulated as "airflow data." Sometimes the airflow is stated as "free air" or is given without reference to the static pressure (SP). Both ignore the flow restrictions imposed by vacuum hose, filters and other system components. Other published rates have never been tested or verified using established industry testing protocols.

I have an obsolete 34 ton Carrier, rooftop, multi-zone, direct expansion unit that I virtually can't get replacement parts for. I need a comparable change out, preferably not a Carrier. Can someone recommend a good substitute, brand, and model number? Also, I have the same scenario with a 20 ton Carrier. We recently bought another home and moved. This home has two dual fuel heat pumps that are zoned. Can you explain exactly how dual fuel heat pumps work.

A 4 cylinder engine requires about 1000 cfm (1700 m^3/h), a 6 cylinder engine requires 1700 cfm (2890 m^3/h) and a small V8 about 2100 cfm (3570 m^3/h). To reach the minimum cfm required you may need to install two or possibly more fans.

To get reliable value for the airflow requirement, you should contact the manufacturer(s) of the servers in the rack. However, in many cases, it may not be possible, and TileFlow provides two alternative methods for estimating the airflow rates. The TileFlow estimate of the airflow rate is based on the specified value of heat load in the rack and a relationship between the heat load and temperature rise across the server, obtained from available data for a large number of servers.

Hello, I have 7 air handling units, 2 of which are supplied by 100% outside air. There is a set of primary, secondary and hepa filters. Both of these units run 24-7. The one units pressure is normal the other one the pressure is always max. I know it is not the gauge because I have 2 different measuring devices. Any ideas or comments. Thanks in advance G.E. We are installing HVAC ducts in a Substation Building.

When number of clients is defined by CLIENTS_NUM_MAX tag, number of CAPS (call attempts per seconds) is resulting from the clients number and load duration for each cycle, comprising from url time for each url with possible redirections, intervals betwee urls and after url interval. The actions and time intervals are configurable in batch file, whereas url retrival time is server and network dependent and not always easy to predict.

This is a short name for "heat loss and gain calculation". This is something that every HVAC contractor should do at the very beginning of every job, but in reality there are very few that will even mention it to you, and if you even ask them about it, they will try to convince you that it is either very expensive or completely unnecessary because there's a "rule of thumb", or press you with their alleged experience and tell you how many thousands of people they have made happy.

TileFlow uses the technique of Computational Fluid Dynamics (CFD), which involves the solution of the mathematical equations governing the physical processes of interest.

Consult the HVI Home Ventilation & Indoor Air Quality Guide for assistance in determining how much airflow (cfm) is appropriate for the room you wish to ventilate. There is also an HVI Certified Home Ventilating Products Directory that lists manufacturers of HVI Certified products with their specifications. Be sure to check your local building code requirements as well.

Just add the power requirements for all the equipment being powered, these details will be in the datasheet for the product under power supply. Then follow the steps described in the APS Configurator on the website. It couldn't be easier.

There are two ways vacuum cleaners work: straight suction from fast moving air, and vibrating or bouncing dirt into the airflow using a beater bar or brush. A vacuum's airflow and air velocity - the volume and speed of air passing through the pickup tool - should pick up debris efficiently while minimizing energy use.

Web space requirements should be calculated keeping in mind the quantity of html pages, graphics, audio and video content and database requirements. You should generally opt for a little more space than you originally calculated as the same may be required to accommodate customer responses and database size growth.

CFM: Is "cubic feet per minute". It is the measure that we use for airflow in vacuum cleaners. The higher the number the more airflow. There are certain parameters that control or restrict CFM, such as pressure, size of the hose, and how many bends.

Yes! Each computer consumes about 300 Watts per hour and does add to the heat of the room. The heat generated from 10 computers needs 1 tonne of air conditioning to keep the room comfortable.

The aim is to give the simplest explanation of the calculation of the winnings in case of a dead heat. The example will be taken from a real and recent race: Prix du Bourbonnais of December 10th, 2005. First, we have to remember that we are talking about parimutuel bets: there is no creation of money, the money of the stakes is distributed after deducting the charges, the taxes..

This is tough to display here... It is the result of the gross model weight divided by the rotor disk area. Radius squared, times 3.14, divided by 144, will give you the square feet. Then take the weight of the model in ounces, and divide this by the square feet, and the result is the disk loading in "ounces per square feet"...........

Yes - WISP contains glycaemic index values for a large number of foods and automatically calculates glycaemic load from food intake records and dietary glycaemic index.

The CFM (Cubic Feet per Minute) is the measurement of how much air passes through the unit. For the HealthMate, the HealthMate+ , and the Allergy Machine™ the fan CFM is 400 cfm on high and 75cfm on low. The HealthMate Jr™ is 200 cfm on high and 50cfm on low.

It varies on wind speed but is equal or greater than the required exhaust vents on the market when used at the soffits. CFM is very hard to compare apples to apples because of all the different variables. Everything would need to be exactly the same for the tests: Outside and Inside Temp., Pressure, wind, same ridge vent, same shingles, same inside living space conditions, same sun rays, etc. etc. etc……..That is why we feel that the industry has chosen NFA to compare products.