3. Engine experimentation

In this section the engine experimental set up, procedure and matrix are included.

The study was conducted on a four-cylinder piston 1Z 1.9 L-66 kW Turbo-Direct injection (TDI) Wolkswagen diesel engine. The engine was fully equipped with a turbocharger with all the necessary sensors and actuators for stable operation of engine. The engine was warmed up to about 94C and the temperature was maintained. The engine was run for 20– 30 min to warm up with the reference DF or test blend fuel. Once the new fuel was pumped in, the engine was made to run for about 20 min to allow for stable operation of the new blend at test fuel conditions. Typical fuel consumption data and brake specific consumption are shown in Table 1. The fuel injection timings for the blends and DF controlled by the electronic diesel control (EDC) for different speeds of 1500, 2500, 3000, and 3500 rpm were 11,11,12, and 15 crank angle BTDC, respectively. The fuel consumption was measured using the AVL 7030 dynamic fuel consumption measuring equipment. Torque was measured by a Borghi and Saveri FE-350S eddy current dynamometer. The study was carried out for 75, 50, and 25% load for engine operating a range of 1500, 2500, 3000, and 3500 rpm. The engine was made to run for each measuring point on steady-state condition for about 2 min before recording values. An average based on three measurements for each test fuel was recorded. The engine operating conditions are shown in Table 2. The in-cylinder indicated pressure (IP) was measured by a piezoelectric pressure transducer Kistler KIAG 600. The top dead center (TDC) crank angle position was measured by an Optical Encoder HENGSTLER RI 32- 0/1024.ER.14KA [21].


Table 1. Typical fuel consumption, λ, BSFC with DF and blends at 1500 and 3000 rpm; A = 100%, and B = 75% load [21].

terms of brake-mean effective pressure (BMEP), or when the engine was running at low speed, the engine's start of injection (SOI) timing was retarded by the EDC in order to meet the

n-Butanol-Diesel (D2) Blend Fired in a Turbo-Charged Compression Ignition Engine: Performance and Combustion…

http://dx.doi.org/10.5772/intechopen.72879

41

Figure 2a and b depict the effect of the blends on manifold boost (air) pressure at 1500 rpm and 3000 rpm, respectively. The increasing boost (air) pressure (above atmospheric of 1 bar) level with BMEP is a measure that helps to improve the brake thermal efficiency (BTE) as the fuel-air

Figure 2. Manifold boost (air) pressure (MAP) vs. BMEP (a) at 1500 rpm (b) at 3000 rpm.

engine's operating conditions.

ratio is reduced.

4.2. Manifold boost (air) pressure

Figure 1. Effect of test fuels on injection timing.


\* Manifold (boost) air pressure (above atmospheric pressure).

Table 2. Operating conditions of engine for fuel D2 [21].

Typical fuel consumption and fuel air ratios are given in Table 1 and operating conditions in Table 2.
