ENGINE INSTALLATION & SERVICE HANDBOOK Caterpillar


Ventilation System Formulas

Usage:



As a rule of thumb, the installer should provide ventilation air flow of about 8 cfm (.22656 m3/min) per installed horsepower. If combustion air is to be drawn from the engine room increase that figure to 91/4cfm (.26196 m3/min).

If you wish to compute more exact engine room air requirements it is necessary to determine the following factors:

H = Heat radiated to the engine room

This data is available from the TMI system for Caterpillar engines. Add in 4 Btu/min per generated 0.07032 kW for the normal maximum auxiliary generator load. Miscellaneous heat loads from other sources (pumps, motors, etc.) can be ignored if they are not exceptional.

Ta = Maximum ambient air temperature the vessel is expected to operate in during its whole life. [Usually assume 110°F (43.3°C).]

Sa = Density of the air at the maximum ambient air temperature.

Density of Air at Various Temperatures

dT = Maximum desired air temperature in the engine room. (Usually assume 10°F (5.6°C) rise above ambient)

When these factors have been determined, the ventilation air requirements in cubic feet per minute (cfm) can be calculated by the following formula:

Qa = Volume of inlet air required in cfm (m3/min)

H = Radiated heat [btu/min (kW)]

Sa = Inlet air density [lbs/cu. ft. (kg/m3)]

0.24 = Specific heat of air (btu/lbs/°F)

0.017 = Specific heat of air (kW·min/kg·°C)

dT = Temperature rise from ambient air to engine air [°F(°C)]

Caterpillar Information System:

ENGINE INSTALLATION & SERVICE HANDBOOK Heat Recovery Systems
ENGINE INSTALLATION & SERVICE HANDBOOK Exhaust System
ENGINE INSTALLATION & SERVICE HANDBOOK Exhaust System Formulas
ENGINE INSTALLATION & SERVICE HANDBOOK Cooling System
ENGINE INSTALLATION & SERVICE HANDBOOK Introduction
C32 Marine Generator (MCS) Electrical System (Interactive) 344-0331 (Engine Alarm and Protection / Generator) 368-7131 (Control Panel) C32 Marine Generator (MCS) Electrical System (Interactive) 344-0331 (Engine Alarm and Protection / Generator) 368-7131 (Control Panel)
C13 XQ350 Power Module Electrical System C13 XQ350 Power Module Electrical System
KENR9596-03 C15 XQ500 Power Module Electrical System (344-5049-01) KENR9596-03 C15 XQ500 Power Module Electrical System (344-5049-01)
C13 Engine For Combat and Tactical Vehicles Electrical System - (Interactive) 348-8676-00 C13 Engine For Combat and Tactical Vehicles Electrical System - (Interactive) 348-8676-00
PM3512 Power Module Electrical System PM3512 Power Module Electrical System
G3512B NSPS and G3512J Engine Electrical System 329-4530-05 G3512B NSPS and G3512J Engine Electrical System 329-4530-05
C27 Head End Power (HEP) Engine Electrical System C27 Head End Power (HEP) Engine Electrical System
ENGINE INSTALLATION & SERVICE HANDBOOK Ventilation Air Duct Sizing
ENGINE INSTALLATION & SERVICE HANDBOOK Combustion Air Formulas
ENGINE INSTALLATION & SERVICE HANDBOOK Sizing Combustion Air Ducts
ENGINE INSTALLATION & SERVICE HANDBOOK Formula for Calculating Horsepower
ENGINE INSTALLATION & SERVICE HANDBOOK Fuel System
ENGINE INSTALLATION & SERVICE HANDBOOK Lubrication System
ENGINE INSTALLATION & SERVICE HANDBOOK Starting System
ENGINE INSTALLATION & SERVICE HANDBOOK Mounting and alignment
ENGINE INSTALLATION & SERVICE HANDBOOK Vibration
ENGINE INSTALLATION & SERVICE HANDBOOK Electrical Fundamentals<SUP><FONT SIZE=-1>*</FONT></SUP>
ENGINE INSTALLATION & SERVICE HANDBOOK Marine Engine Performance Analysis
ENGINE INSTALLATION & SERVICE HANDBOOK Cat Marine/Industrial Engine Diagnostic Codes
Back to top
The names Caterpillar, John Deere, JD, JCB, Hyundai or any other original equipment manufacturers are registered trademarks of the respective original equipment manufacturers. All names, descriptions, numbers and symbols are used for reference purposes only.
CH-Part.com is in no way associated with any of the manufacturers we have listed. All manufacturer's names and descriptions are for reference only.