State any TWO ways by which air turbulence can be improved during the intake stroke on a direct injection diesel engine.

Step 1: Identify components A to E in FIGURE 2. A points to the device that injects fuel into the chamber. B points to the heating element used for cold starts. C points to the moving part that compresses the air. D points to the enclosed space where initial combustion occurs, separate from the main cylinder. E points to the narrow opening connecting the pre-combustion chamber to the main cylinder. Step 2: Determine the type of pre-combustion chamber shown. The chamber labelled D is a compact, often spherical or pear-shaped, chamber connected to the main cylinder by a narrow passage (E). This design promotes a swirling motion of air, which is characteristic of a swirl chamber. Step 3: List two types of indirect combustion chambers. Indirect combustion chambers are designs where combustion begins in a separate chamber before expanding into the main cylinder. Common types include the swirl chamber and the air cell chamber. 6.4.1) A: Fuel injector B: Glow plug C: Piston D: Pre-combustion chamber E: Throat / Passage 6.4.2) This is a swirl chamber. 6.5) Two types of indirect combustion chambers are: • Swirl chamber • Air cell chamber