Page 232 - Handbook of Energy Engineering Calculations

During the year the engine operates 24 h/day for 300 days. Hence, the
annual intake of dust is (24 h/day)(300 days/year)(336 gr/h) = 2,419,200 gr
(156.8 kg). Since there is 7000 gr/lb, the weight of dust entering the engine
per year = 2,419,200 gr/(7000 gr/lb) = 345.6 lb/year (155.5 kg/year).

3. Compute the filtered dust load

With the air filter removing 80 percent of the dust, the quantity of dust
reaching the engine is (1.00− 0.80)(345.6 lb/year) = 69.12 lb/year (31.1
kg/year). This shows the effectiveness of an air filter in reducing the dust and
dirt load on an engine.

Related Calculations. Use this general procedure to compute the dirt load on
an engine from any external source.

ENERGY PERFORMANCE FACTORS FOR I-C ENGINES

Discuss and illustrate the important factors in internal-combustion engine
selection and performance. In this discussion, consider both large and small
engines for a full range of usual applications.

Calculation Procedure:

1. Plot typical engine load characteristics

Figure 11 shows four typical load patterns for internal-combustion engines. A
continuous load, Fig. 11a, is generally considered to be heavy-duty and is
often met in engines driving pumps or electric generators.
Intermittent heavy-duty loads, Fig. 11b, are often met in engines driving

concrete mixers, batch machines, and similar loads. Variable heavy-duty
loads, Fig. 11c, are encountered in large vehicles, process machinery, and
similar applications. Variable light-duty loads, Fig. 11d, are met in small
vehicles like golf carts, lawn mowers, chain saws, etc.