ACS DRIVE-IN CHAMBERS PART 1: VEHICLE EMISSION TESTING

Main design problems in the automotive field

• Time to market is a must for success of new car models.
• Quality reliability safety and environment friendly components are key points for modern vehicles, the check of those items is necessary to ensure warm welcome into the market.
• In order to improve the efficiency of the project phase, improvements of testing devices are requested to perform tests combining several types of stress simulating the real vehicle working.
• The standardization of test methods is necessary to compare different test results, so strict cooperation between users and producers of test equipment helps to reach that goal through the experience of each side.

Purpose of the test

• Fluid dynamic efficiency of the vehicle
• Emission test
• HVAC efficiency performance test

Test features

Freon direct expansion

• Key points
  • Quick achievement of the set point
  • Low energy consumption
  • Higher MTBF
• Weak points
  • Defrosting after the test is required
  • Slightly higher noise

Indirect system

• Key points
  • Defrosting is not required
  • Good accuracy
• Weak points
  • Continuous maintenance is required
  • High consumption
  • Low performance

Piston type

• Key points
  • Chamber can work even if one of the compressors is out
  • Reasonable noise
  • Possibility to work in cascade configuration to increase the temperature rates of the chamber
• Weak points
  • Continuous maintenance is required
  • High consumption
  • Remarkable footprint of the cooling plant

Screw type

• Key points
  • Frequent maintenance is not required
  • High energy efficiency
  • High MTBF it means good reliability
• Weak points
  • High noise
  • No chance to work in case of failures
  • Not useful for low powers

Air Removal System by Mechanical Cooling

• Key points
  • Frequent maintenance is not required
  • High energy efficiency
  • Not contaminated air into the chamber
• Weak points
  • Continuous defrosting is required
  • Remarkable footprint of the cooling plant

Air Removal System by Chemical Dryer

• Key points
  • Compact footprint
  • Defrosting is not required
• Weak points
  • Frequent maintenance is required
  • High energy consumption
  • Air contaminated by the chemical parts