Indicator Diagrams Flashcards
What is a PV Diagram?
A PV diagram, also known as a Pressure-Volume diagram, is a graphical representation of the pressure-volume relationship during the engine’s operational cycle. It is a fundamental tool used to analyze and understand the thermodynamic processes occurring within the engine cylinder throughout the engine cycle.
Explain an understanding of draw cards and what indicates an issue with them?
A draw card is used to determine compression pressure, peak pressure and engine power.
They can show signs of misfiring, poor combustion, abnormal peak pressures and valve timing.
Power cards, faults, causes, fixes, big engine stuff.
A fault could be reduced power caused from poor combustion, checking the air filters and fuel injectors to rectify.
Knocking caused from early ignition, can be solved by adjusting the fuel timing.
What factors affect power output?
- Fuel quality
- Fuel timing
- Fuel pressure
- Air flow
- Valve clearance
- Worn piston rings
- Overheating
Define torque?
It is a measure of the force that causes an object to rotate or twist around an axis and is commonly expressed in units of force.
How does a torque meter work?
When torque is applied to the shaft, it undergoes deformation due to the applied torque. This deformation causes a change in the length and shape of the shaft, which in turn induces strain in the strain gauges bonded to the surface of the shaft and therefore provides a reading.
How do you know an engine is overloading?
- Increased exhaust temperature
- Higher cylinder pressure
- Increased fuel consumption
- Excessive black smoke
- Increased vibration and noise
