Our Combustion Air Handling Units (CAHU), pronounced “Cah-Who”, condition ambient air elements to generate a consistently accurate and highly repeatable supply of conditioned air to the engine intake. 

CAHU system range is scalable for flow rates to satisfy a wide range of flow rates. Controlled by our CADET V14 software, the CAHU conditioned air is ideal for emissions work, for standardising the engine intake air conditions for mapping or optimization and for simulating ambient conditions from around the globe.

Key Features:

  • The CAHU improves test cell productivity by reducing test days lost due to adverse atmospheric conditions.
  • CAHU’s eliminate the need for correction factors and can be used for standardisation of conditions or to simulate an alternative set of ambient conditions.
  • Three main versions are available PTH (Pressure, Temperature and Humidity), TH (Temperature and Humidity) and T (Temperature only).

Sierra CP offer several versions of CAHU

PTH CAHU

T CAHU & TH CAHU

HS CAHU

CAHU Boost Rig

PTH CAHU

This CAHU cools and condenses the air feed to a base level, humidity and heat is then added to the flow to reach the required target setpoints.

The CAHU conditions all the air that may be consumed, so it is always available, any air not consumed is dumped through a silencer, this provides a highly transient and responsive product.

The PTH controls the dump valve to regulate the pressure fed into the engine. The CAHU requires an external chilled water feed, electrical power and tap water supply, otherwise it is self-contained with it’s own electric steam generator. It can provide pressure setpoints of up to 80mBar (8kPa) above or below ambient pressure conditions.

The PTH CAHU is built into a stainless steel frame with panels, it is considered as movable but not portable, it should be connected via a rigid smooth bore thermally lagged delivery duct. To achieve pressure control the duct should be close coupled to the engine to enable the positive and negative pressures. 

Request A Consultation

T CAHU and TH CAHU

The T CAHU and TH CAHU cools and condenses the air feed to a base level, humidity and heat is then added to the air flow to reach the required target setpoints.

A single fan provides the flow capability through the system. If there is sufficient flow the CAHU can provide multiple output locations simultaneously.

The CAHU conditions all the air that may be consumed by the engine plus an excess of approximately 10%, the air floods the intake of the engine with excess air so the engine only draws on conditioned air.

The CAHU requires an external chilled water feed, electrical power and tap water supply, otherwise it is self-contained with it’s own electric steam generator. 

The T CAHU and TH CAHU is built into a frame which is mounted on castors, this enables it to be moved between locations. At only 800mm (32”) wide it can be wheeled through a single personnel doorway.

Request A Consultation

HS CAHU

Our High Specification CAHU’s enable the race engine developer to recreate ambient conditions in terms of temperature, pressure and humidity to simulate the conditions of race tracks from around the globe on a real time transient basis.

Improvements to functionality now enable setpoint control of humidity as value of % RH. 

In addition, an absolute humidity value of g/kg provides better set point control through an operating range independent of temperature.

Tolerances and components quality are all stepped up in line with the demands of the clientele.

Request A Consultation

Boost Rig

Our Boost rig was designed for turbo simulation projects, with dynamic controllable regulation of the air pressure and temperature and humidity conditioning.

  • A high volume compressed air feed is required, the boost rig then cools or heats the air with a heat exchanger and a dynamic electric heater element respectively.
  • If humidity setpoint is required then a high pressure steam system will supply our humidity injection system.
  • The flow is fed to the engine and the dump valve regulates the pressure at the engine.
  • As with the CAHU, to achieve high transients we condition all the rated air and dump excess to enable fast control.

If you require the high flow rate compressor and the high pressure steam system Sierra CP can quote for these sub systems. 

Request A Consultation

We also build Altitude Simulation systems

For the current trend of altitude simulation of combustion engines Sierra-CP has two standard offerings but can also customise to suit your specific requirements.

EXPLORE PRODUCTS