Overview
The project defined the optimal turbocharged diesel engine and the integration studies to make use of the engine for the ideal helicopter platform. The positive results of the project demonstrated a substantial potential for pollutant emission and fuel consumption reduction by powering light single engine category helicopter with this advanced diesel engine instead of a conventional small turboshaft engine. The study consisted of three major phases:
- Optimal Diesel Engine Specification,
- Engine/Rotorcraft Integration Study,
- Environmental Impact Analysis.
The technical challenge was to obtain the power-to-weight ratio taking into account helicopter requirements such as reliability and TBO. An optimal diesel engine was chosen by selection procedure, where ratings criteria will use performance, weight, size, fuel economy, emissions, multi-fuel capability, reliability, noise, technology, costs, integration, cooling, and drag. Engine configuration was selected from the several types of engines which were modelled and compared. Finally, the very small engine with the defined engine sub-systems were designed. To solve the design problems, the applicant used his experience, workforce and knowledge in applying held designing tools to design aircraft and automotive piston engines: CFD software (Fluent, AVL FIRE), CAD software (Catia v5, Patran Package), FEM software (ABAQUS, MD Nastran), object oriented modelling tools (AVL BOOST, Dymola Modelica, MD Adams).
The project predicted many obstacles like vibration, noise, transmission chain coupling and torque oscillations, engine control and response. To solve these problems, the innovative ideas were proposed to develop and analyse the high dimensional dynamics of the multi-body mechanical system and the original diesel engine adaptive control system.
Funding
Results
Executive Summary:
The optimal diesel engine designed for the light helicopter was assumed to reach an ideal helicopter characteristic and fulfil the environmental impact reduction expectations according to the ACARE goals for year 2020 as defined in the call.
The main goal of the project was to define the optimal turbocharged diesel engine and the integration studies to make use of the engine for the ideal helicopter platform. The results of the project demonstrate a substantial potential for pollutant emission and fuel consumption reduction by powering the light single engine category helicopter with this advanced diesel engine instead of a conventional small turboshaft engine.
Hence, the research and development work in DELILAH was based on the following deliverables:
- Engine Specification – Engine General Description;
- Engine Specification – Subsystems;
- Engine Specification – Thermodynamic Analysis;
- Engine Specification – Engine Vibration Characteristics;
- Engine Specification – Engine Control System;
- Engine Specification – Interface Control Document;
- Environmental impact report.
The technical challenge has been to obtain the power-to-weight ratio taking into account helicopter requirements such as reliability and TBO. An optimal diesel engine has been chosen by selection procedure where ratings criteria will be based on performance, weight, size, fuel economy, emissions, multi-fuel capability, reliability, noise, technology, costs, integration, cooling, and drag. The engine configuration has been selected from the several types of engines. Finally, the engine with the defined engine sub-systems has been designed. To solve the design problems designing tools to design aircraft and automotive piston engines have been applied. The project relates to the solution of problems like: vibration, noise, transmission chain coupling and torque oscillations, engine control and response. To solve these problems, the innovative ideas have been done to develop and analyse the high dimensional dynamics of the multi-body mechanical system and the original diesel engine adaptive control system.
The project of a full authority digital engine controller (FADEC) has been developed. The project includes the fuel injection system and takes into account the numerous variables of the engine with respect to exhaust gas emission, combustion pressure, EGT, torque, and engine speed limits.
To establish the environmental benefits of the diesel engine technologies, mathematical models have been created and the performance and environmental impact of an advanced diesel engine light helicopter have been calculated, incorporating project technology developments. This phase is preceded by an analysis of the flight scenario. The performance of the helicopter is inseparably related to the load at the input to the propulsion system. With an increasing focus on reducing the use of fossil fuel to minimize climate change, there have been performed the calculations using not only usual diesel fuel but also biofuels and biomass-to-liquids (BTL) diesel fuel. The results have shown that the use of biofuels reduces nitrogen oxide emissions but increases soot emission.