Conventional DPF Testing

Diesel Particulate Filters
Traditionally DPFs have been tested in a variety of ways, combining cold flow bench tests with measurements of backpressure made using an engine and dynamometer to produce soot. The former use artifical soot, with markedly different characteristics to engine generated soot. While widely adopted, engine dynamometer testing requires expensive facilities and staff, and extreme care must be taken to ensure good repeatability and reproducability. The interaction between engine and DPF means that evaluation of different DPFs on a given engine platform may be extremely complex.

The Cambustion DPG Solution

Soot Loading

Schematic of air and fuel flows inside Cambustion DPF Testing System

The dependence of filter backpressure (Δp) on the soot load on a filter is a very important quality control parameter for modern engine control strategies where a backpressure sensor is used in the triggering of filter regenerations. The DPG loads a filter from an empty state and continually monitors Δp and automatically processes the results using loaded and empty weighings of the filter to provide a far better measurement of loading behaviour than is achievable with engine testing.


Control over the DPF inlet conditions allows the DPG to regenerate filters. This can provide a simple means of de-greening filters, regeneration after soot loading tests, or allow more complicated studies such as Soot Mass Limit tests, where the DPG's improved reproducibility and repeatability offer substantial advantages.

Cold Flow Tests

The DPG may also make cold flow tests, and results may be corrected to any set of reference conditions.


The DPG has lower infrastructure and operation costs than an engine dynamometer.

Further, the computer control allows the system to operate unmanned for substantial portions of the test- only requiring operator input to weigh or change DPFs.

The DPG allows customers to study the behaviour of a filter without the corresponding difficulties associated with engine tests, avoiding issues such as passive regeneration due to NOx and engine / DPF interactions due to backpressure.

The DPG allows the DPF to be preheated to the loading temperature and flow conditions, while not producing any soot. The burner settings are then automatically switched to a soot producing mode while maintaining the same DPF inlet conditions. This allows the pore filling stage of filtration to be studied in unprecedented detail.


For a list of Application Notes which offer detailed guidance on common uses of the DPG, click here.

In production quality assurance applications the DPG allows validation of backpressure characteristics, filtration efficiency and regeneration performance.

In an R&D environment it provides economic and repeatable soot loading of DPFs to support engine and after-treatment development.

DPG: DPF Testing System

Filter Test Housing accessory for bare brick testing

Cambustion offer a Filter Test Housing (FTH) for use with the DPG. This reusable DPF housing allows an uncanned filter to be fitted to the DPG and loaded / regenerated as required. The filter can be quickly removed for weighing and examination, even at elevated temperatures.

This ability is particularly advantageous in both R&D and Quality Control applications, and allows filters to be tested before coating or other final processes take place.

For further information, please download the DPG brochure or contact Cambustion.

DPF Testing Service

Cambustion also offer a DPF loading / testing service, using the DPG. For more information please see our Engineering Services pages.

Key Application Notes: 
Title Data type Download File Size Last updated
Soot load vs DP characteristic measurement on the DPG Application note PDF icon DPG 001v02 Soot load vs DP.pdf 1022.77 KB 24-Feb-2015
DPF efficiency measurements with the DPG Application note PDF icon DPG 002v01 DPF efficiency measurement.pdf 200 KB 24-Feb-2015
Cold flow DPF testing with the DPG Application note PDF icon DPG 003 Cold flow testing.pdf 172.47 KB 24-Feb-2015
Automated Soot Mass Limit determination with the DPG Application note PDF icon DPG 004 Automated SML determination with DPG.pdf 704.21 KB 24-Feb-2015
Cut to idle regeneration Application note PDF icon DPG 005 Cut to Idle Regen.pdf 125.15 KB 24-Feb-2015
Comparison of DPG and engine soot Application note PDF icon DPG 006v01 DPG vs engine soot.pdf 216.83 KB 24-Feb-2015
DPG Repeatability Application note PDF icon DPG 007 DPG Repeatability.pdf 95.33 KB 24-Feb-2015
Max Soot Load - Zoned Regeneration Application note PDF icon DPG 009 MSL Regen - zoned loading.pdf 133.83 KB 24-Feb-2015
Sub-scale and oxygen control accessories PDF icon DPG 010v02.pdf 907.96 KB 15-Apr-2015
Gasoline Particulate Filter (GPF) testing Application note PDF icon DPG012v01 GPF testing.pdf 131.51 KB 27-Jun-2016