Chapter 7.1 TurboProp Engine v1 PDF
Document Details
Uploaded by WiseCreativity
School of Mechanical & Aeronautical Engineering
Tags
Summary
This document provides an overview of TurboProp Engines, including introduction, facts, advantages, features, example, and assembly. It also describes negative torque signal (NTS), thrust sensitive signal (TSS) and reduction gear assembly. Details about the recap are provided at the end.
Full Transcript
Chapter 7.1: TurboProp Engine Introduction Facts On Turbo-prop Engines Turbo-Propeller Assembly Negative Torque Signal (NTS) Thrust Sensitive Signal (TSS) Reduction Gear Assembly 2 Facts on Turboprop Engine Shaft horse-power is the measure o...
Chapter 7.1: TurboProp Engine Introduction Facts On Turbo-prop Engines Turbo-Propeller Assembly Negative Torque Signal (NTS) Thrust Sensitive Signal (TSS) Reduction Gear Assembly 2 Facts on Turboprop Engine Shaft horse-power is the measure of the output of these gas turbine engines. Advantages of Turboprop Engine ▪ Rapid acceleration for take-off ▪ Efficient at low altitude and low air speed ▪ Short landing roll due to prop braking action ▪ Low vibration ▪ High power (engine) -to-weight (aircraft) ratio Features of Turboprop Engine ▪ Gear reduction drive ▪ Free turbine ▪ Counter-rotating spools ▪ Reverse pitch ▪ Negative Torque Signal ▪ Thrust Sensitive Torque Signal 3 Examples of Turboprop Engine 4 Turbo-propeller Assembly 5 Turbo-Propeller Assembly The spinner assembly is a cone-shaped configuration to reduces drag. The after-body assembly is a non rotating component mounted on the gear box to enclose the control assembly. The control assembly is a non-rotating assembly that contains the oil reservoir, pumps, valves and control devices, which supply hydraulic power for pitch control on the propeller. The synchronophasing system is designed to synchronise the pitch angle between multiple propellers. 6 Negative Torque Signal (NTS) 7 Negative Torque Signal (NTS) Control System The NTS control system provides a signal during sign of negative torque. It increases the propeller blade angle to limit negative shaft torque. Negative torque happens when during temporary fuel interruptions, air gust loads on the propeller and normal shutdown. 8 Thrust Sensitive Signal (TSS) The TSS (thrust sensitive signal) is a safety feature, which actuates the propeller feather lever. If a power loss occurs during takeoff, propeller drag is limited to that of a feathered propeller, reducing the hazards of yawing in multi-engine aircraft. This device automatically increases blade angle to 90o and causes the propeller to feather. 9 Free Turbine Free Turbine is define as turbine not mechanically connected to the compressor while extracting energy from the gas to do work 10 Reduction Gear Assembly 11 Reduction Gear Assembly The reduction gear assembly will consist on single propeller drive shaft, NTS system, a TSS system, safety coupling, propeller brake, an independent dry sump oil system and the necessary gears. The brake is to prevent wind-milling effect on the propeller blade. 12 Recap Measuring unit of Turboprop power output Describe the functionality of synchronophasing system of the turboprop engine Describe the functionality of NTS system of the turboprop engine Describe the functionality of TSS system of the turboprop engine The components involved in the reduction gear assembly 13
