Valve lift & variable air flowrate in compressed air

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SUMMARY

This discussion focuses on incorporating valve lift and variable flow rate in compressed air engines, emphasizing the relationship between mechanical power and air power. Key calculations include determining mass flow into the cylinder as a function of valve lift and crank angle, and calculating torque using the formula T = p*A*dx/dtheta. The conversation highlights the importance of understanding how turbulence affects the energy conversion from fluid flow to mechanical power.

PREREQUISITES
  • Understanding of mechanical power equations in fluid dynamics
  • Knowledge of valve lift mechanics in engine design
  • Familiarity with mass flow calculations in compressed air systems
  • Basic principles of torque and angular velocity relationships
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  • Research "mass flow rate calculations in pneumatic systems"
  • Study "valve lift impact on engine performance"
  • Explore "turbulence effects on energy conversion in fluid dynamics"
  • Learn about "compressor design for variable flow rates"
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Engineers, mechanical designers, and researchers focused on optimizing compressed air engines and enhancing performance through advanced fluid dynamics principles.

Chotai Nikhil
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How we can incorporate valve lift and variable flow rate in compressed air engine

Mechanical power = air power
torque * angular velocity = pressure * flow rate
 
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There's a lot to your question. Are you asking how to calculate the flow into the cylinder as a function of valve lift?
I don't believe your second expression is that useful. The power produced by the motor (it's not an "engine" because it doesn't run on heat) will be equal to the force on the piston times the piston speed (p*A*dx/dt), but not equal to the rate of energy coming in with the fluid. This is because some of the enthalpy of the incoming flow, through turbulence, will be converted to heat.
You'll need to calculate the mass-flow into the cylinder to get pressure as a function of crank angle theta, and calculate torque from T = p*A*dx/dtheta.
 
Thank you sir

1) I used the Word Engine because i modified the 4 stroke petrol engine to 2 stroke engine

2) how does i incorporate flow rate instead of Pressure "P" because i have flow through valve here and i don't have exact value of Pressure of P incise the cylinder which we call as mean pressure in petrol engine.
 

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