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Can type combustors are robust, with ease of design, manufacturing and testing. They are extensively used in industrial gas turbines and aero engines. This paper is mainly based on the work carried out in designing and testing a can type combustion chamber which is operated using JET-A1 fuel. Based on the design requirements, the combustor is designed, fabricated and tested. The experimental results are analysed and compared with the design requirements. The basic dimensions of the combustor, like casing diameter, liner diameter, liner length and liner hole distribution are estimated through a proprietary developed code. An axial flow air swirler with 8 vanes and vane angle of 45 degree is designed to create a re-circulation zone for stabilizing the flame. The Monarch 4.0 GPH fuel nozzle with a cone angle of 80 degree is used. The igniter used is a high energy igniter with ignition energy of 2J and 60 sparks per minute. The combustor is modelled, meshed and analysed using the commercially available ansys-cfx code. The geometry of the combustor is modified iteratively based on the CFD results to meet the design requirements such as pressure loss and pattern factor. The combustor is fabricated using Ni-75 sheet of 1 mm thickness. A small combustor test facility is established. The combustor rig is tested for 50 Hours. The experimental results showed a blow-out phenomenon while the mass flow rate through the combustor is increased beyond a limit. Further through CFD analysis one of the cause for early blow out is identified to be a high mass flow rate through the swirler. The swirler area is partially blocked and many configurations are analysed. The optimum configuration is selected based on the flame position in the primary zone. The change in swirler area is implemented in the test model and further testing is carried out. The experimental results showed that the blow-out limit of the combustor is increased to a good extent. Hence the effect of swirler flow rate on recirculation zone length and flame blow out is also studied and presented. The experimental results showed that the pressure loss and pattern factor are in agreement with the design requirements.

In this study, the combustion and exhaust emission characteristics of a single‐cylinder, water‐cooled, four‐stroke VCR engine at a fixed CR were evaluated using DME and diesel with timed manifold injections of 2, 3, 4, and 5 ms for DME and conventional diesel settings. The investigational trials showed that DME has the capability to reduce NOx and OP while used in an optimized range and to have clean combustion characteristics. Induction of DME under low to medium load conditions resulted in a reduction in NOx, OP, and BTE with an increase in HC, whereas at higher load settings, NOx increased with an increase in diesel energy share. The dual fuel combustion was characterized by a short ignition delay, an early start of combustion, and increased in‐cylinder pressure due to the increased compression work input during the cycle. The absence of carbon–carbon bonds in DME molecules caused low soot emissions during dual fuel combustion. After experimentation, RSM was applied to the results for parametric optimization and found to be a useful tool for reducing the error as well as minimizing the number of trials. The optimum settings were achieved at 2 kW load and 4 ms duration, where the desirability function reached a value of 0.94189. The regression equations developed by the model were validated by 9 random experiments, and the error is found to be acceptable. The engine should be operated at medium load to control NOx, and the DME energy share should be low and near 50%.