Loading presentation...

Present Remotely

Send the link below via email or IM

Copy

Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

DeleteCancel

Make your likes visible on Facebook?

Connect your Facebook account to Prezi and let your likes appear on your timeline.
You can change this under Settings & Account at any time.

No, thanks

Smart cooling fan (PWM speed controlled)

Mechatronics Master's Fall 2012
by

mostafa arafa

on 25 November 2014

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Smart cooling fan (PWM speed controlled)

Temperature Based Fan Speed Control in Engine Cooler
EngineCoolingSystem
Engine Cooling System Basically Consists of:
Heat Exchanger (Radiator).
Thermostat Valve.
Expansion Coolant Tank.
Water channels in Engine block and cylinder head.
Fan (For air cooling).
Problem-solving cycle on the micro-level
Operating temperature is the most important parameter in engine performance and service life.

Engine overheating affecting all engine characteristics, performance, service life, and operating economics.

The purpose of the engine fan is to allow the engine to run at its regulated operating temperature to increase engine performance.
Basic system to be Studied
Fan (Air cooling system) - Adoption of Goals & Situation analysis
The Goal:
Engine temperature is varying according to heat generated from variable rate fuel burning so, variable controlled speed fan is a must to keep engine temperature in the desired zone.

Reduce engine fan noise, fan loading on the engine and improve fuel economy under all operating conditions.

The system to be considered is the passenger cars class.
Adoption of Goals & Situation Analysis
Alternatives synthesis and analysis
1. Crank direct operated fan
Simplicity is the
advantage
of this system.
Disadvantages:
Poor controllability.
Over-cooling.
Power losses.
Affecting engine service life.
1
2
2. Using of thermal (on/off) switches
Normally closed (opening on temperature rise), or normally open (closing on temperature rise) bi-metallic switches, which automatically reset within a close tolerance band.
Advantages:
More power efficient than the previous.
Simple construction.

Disadvantages:
Bad cooling rate.
Low accuracy.
Not suitable for all engine regimes.
Power losses.
Noise.
3
3. Hydraulic powered cooling fans
Advantages:
Precise control.
Low power loses.
Very high speed varying ranges.
Very low noise generation.
Flexibility to design and assemble the cooling system.
Disadvantages:
Very expensive.
Suitable for large diesel engines.
Not suitable for petrol / small diesel engine.
4
4. Programmable control dc motor powered fan (this project)
Benefits of this system:
Precise control leads to accurate engine temperature.
Suitable for petrol / diesel engines up to 200 hp.
Improve economics, and engine service life.
Low noise.
Stepless control method.
Decision
4. Programmable control dc motor powered fan (this project)
Programmed fan control can reduce engine fan noise, fan loading on the engine and improve fuel economy under all operating conditions.
V-model on the Macro Level
Keep the engine coolant temperature at 65±2 (at the outlet of the radiator).
Controlling temperature of passenger cars' engines. (Maximum Brake horsepower 100 BHp)
System Requirements
Basic Structure of the system:
Mechanical Engineering
Fan Sizing
The Design requirements:
the cooling system can operate at ambient temperature 20~60 Clesuis.
maximum idling power of the engine is 10 BHp. (10% of maximum BHp)
Based on the calculations the maximum air flow required is 678 CFM.
Electrical Engineering
Design Requirements
Maximum voltage available is 12 VDC.
Maximum air flow required from the Electric fan is 678 CFM.
Electric Actuator Selection
DC motors fulfill the above requirements.
Based on the system requirement above; referring to an auto radiator fan supplier catalog we determined the required model to be used according to our conditions specified.
Electrical Fan Selection
Control Engineering
Design requirements:
Maintain the coolant outlet temperature @ 65±2 Clesius.
This cooling system shall work efficiently @ ambient temperature 20~60 Clesius.
Based on the above requirements a temperature control loop shall be developed.
Temperature Sensor Selection:
Thermocouples are inexpensive, fast response time but are less accurate and the least stable and sensitive. Thermocouples also read only relative temperature difference between the tip and the leads while RTDs and thermistors read absolute temperature.

RTDs are the best choice for repeatability, and are the most stable and accurate. However they have a slow response time and because they require a current source they do have a low amount of self heating.

Thermistors have a fast output and are relatively inexpensive but are fragile and have a limited range. They also require a current source and do experience more self heating than an RTD and are nonlinear.
Micro-controller Specifications:
The Arduino Uno is a micro-controller board based on the ATmega328 running on a 16 MHz ceramic resonator.

Arduino Uno peripherals:
14 digital input/output pins (of which 6 can be used as PWM outputs).
6 analog inputs.

Modeling
Laboratory Specimen:
Mapping between actual system and prototype
Actual System
Prototype
Basic System
Sensors
Information Processing
Actuators
Information
Energy
Material
Basic Mechatronic System Configuration
Basic System
Sensors
Information Processing
Actuators
Information
Energy
Material
Information Processing
Vehicle Management System
Basic System
Sensors
Information Processing
Actuators
Information
Energy
Material
Basic System
Sensors
Information Processing
Actuators
Information
Energy
Material
Basic System
Sensors
Information Processing
Actuators
Information
Energy
Material
Basic System
Sensors
Information Processing
Actuators
Information
Energy
Material
Basic System
Sensors
Information Processing
Actuators
Information
Energy
Material
Engine Management System
Transmission Control Unit
Full transcript