Main Engine Turbocharger Function Quiz

To increase engine power output by compressing the air before it enters the engine cylinders, allowing more fuel to be burned and increasing efficiency.

The term pulse system refers to a turbocharging system where exhaust gas flows in pulsating form into the turbine, with each gas pulse fed to a corresponding nozzle ring segment of the expansion turbine.

The pulse system allows for efficient scavenging of the engine cylinders by overlapping the opening times of inlet and exhaust valves after the pulse decay, resulting in better performance compared to the constant pressure system.

<p>Advantages include increased engine power output, reduced specific fuel consumption, lower initial engine cost, space savings, increased reliability, and reduced maintenance costs.</p> Signup and view all the answers

<p>A turbocharger comprises a gas turbine driven by the engine exhaust gases mounted on the same spindle as a blower, with the power generated in the turbine equal to that required by the compressor.</p> Signup and view all the answers

<p>Undercooling the charge air can lead to reduced engine efficiency and power output, potentially causing incomplete combustion and increased emissions.</p> Signup and view all the answers

<p>Fins are attached to the tubes to increase the surface area for better heat transfer between the air and the cooling medium.</p> Signup and view all the answers

<p>Zinc anodes are sacrificial elements that help prevent galvanic corrosion by corroding themselves instead of the main structure of the cooler.</p> Signup and view all the answers

<p>Vent cocks are used to release trapped air from the system, ensuring optimal heat transfer efficiency by eliminating air pockets.</p> Signup and view all the answers

<p>Tube fins increase the surface area of the tubes, enhancing heat transfer efficiency by promoting better contact between the air and the tube surface.</p> Signup and view all the answers

<p>Fouling of air passages can restrict airflow, leading to reduced efficiency in the combustion process, lower power output, and potentially increased fuel consumption.</p> Signup and view all the answers

<p>The air seal, maintained by a fitted rubber joint ring, prevents leaks and ensures that the charged air flows through the designated passages for effective cooling.</p> Signup and view all the answers

<p>The cast iron water boxes are attached to the tube plates and facilitate the circulation of cooling water, allowing for efficient heat dissipation from the tubes.</p> Signup and view all the answers

<p>A change in 'Mass Air Flow'.</p> Signup and view all the answers

<p>The compressor end of the rotating element.</p> Signup and view all the answers

<p>Air will attempt to flow back through the rotating impeller.</p> Signup and view all the answers

<p>It throws the rotating element into a vibration, producing a barking noise.</p> Signup and view all the answers

<p>Like a centrifugal pump attempting to pump against a closed valve.</p> Signup and view all the answers

<p>Surging causes vibrations due to the back flow of air through the rotating impeller.</p> Signup and view all the answers

<p>Surging reduces the efficiency of the turbocharger.</p> Signup and view all the answers

<p>Surging can reduce the power output of the engine.</p> Signup and view all the answers

<p>The Pressure Ratio Increases</p> Signup and view all the answers

<p>The Pressure Ratio will suddenly drop over the edge of the graph causing a sudden pressure drop, leading to Turbocharger Surge.</p> Signup and view all the answers

<p>Pressure in the scavenge space being higher than that being delivered by the blower.</p> Signup and view all the answers

<p>Pressure Ratio suddenly dropping over the edge of the graph.</p> Signup and view all the answers

<p>To create an operating line across various speeds of the Turbocharger.</p> Signup and view all the answers

<p>The Pressure Ratio Increases</p> Signup and view all the answers

<p>Pressure Ratio will suddenly drop over the edge of the graph, causing a sudden pressure drop.</p> Signup and view all the answers

<p>Turbocharger Surge</p> Signup and view all the answers

<p>To prevent debris and contaminants from entering the turbocharger, which can cause damage and reduce efficiency.</p> Signup and view all the answers

<p>To remove heavy fuel deposits that can accumulate and affect the turbocharger's performance.</p> Signup and view all the answers

<p>To increase the air intake pressure into the engine, allowing for better combustion and increased power output.</p> Signup and view all the answers

<p>A thrust bearing is needed to withstand the axial loads generated by the turbocharger rotor.</p> Signup and view all the answers

<p>Heavy fouling, worn bearings, air leaks, and excessive exhaust gas temperature.</p> Signup and view all the answers

<p>The pulse system refers to a method of turbocharging where exhaust gas pulses are used to drive the turbine.</p> Signup and view all the answers

<p>The pulse system provides quicker response and better low-end torque compared to the constant pressure system.</p> Signup and view all the answers

<p>To ensure balanced power output and performance across all cylinders, preventing uneven stress and wear.</p> Signup and view all the answers

<p>The turbocharger is lubricated by engine oil, which is supplied through dedicated oil lines to reduce friction and heat.</p> Signup and view all the answers

<p>Potential causes can include imbalance, misalignment, worn bearings, worn compressor or turbine wheels, or foreign object damage.</p> Signup and view all the answers

<p>Minimization can be achieved through regular maintenance, proper alignment, balancing, use of quality parts, and avoiding foreign object damage.</p> Signup and view all the answers

<p>Surging can reduce efficiency by causing fluctuations in airflow and pressure, leading to potential damage to the turbocharger components.</p> Signup and view all the answers

<p>The thrust bearing helps to counteract axial thrust forces generated by the turbocharger rotor, ensuring stable and reliable operation.</p> Signup and view all the answers

<p>The analogy of 'coughing and barking' is often used to describe the noise produced when air flows back through the turbocharger impeller.</p> Signup and view all the answers