Preliminary Studies on Non-Reactive Flow Vortex Cooling

Background: The impulse for the propulsion of a rocket engine is obtained from the combustion of propellant mixture inside the combustion chamber and as the plume exhausts through a convergent- divergent nozzle. At stoichiometric ratio, the temperature inside the combustion chamber can be as high as 3500K. Thus, effective cooling of the thrust chamber becomes an essential criterion while designing a rocket engine. Objective: A new cooling method of thrust chambers was introduced by Chiaverni, which is termed as Vortex Combustion Cold-Wall Chamber (VCCW). The patent works on cyclone separators and confined vortex flow mechanism for providing high propellant mixing with improved degree of turbulence inside the combustion chamber, providing the required notion for studies on VCCW. The flow inside a VCCW has a complex structure characterised by axial pressure losses, swirl velocities, centrifugal force, flow reversal and strong turbulence. In order to study the flow phenomenon, both the experimental and numerical investigations are carried out. Methods: In this study, non-reactive flow analysis was conducted with real propellants like gaseous oxygen and hydrogen. The test was conducted to analyse the influence of mixture ratio and injection pressure of the propellants on the chamber pressure in a vortex combustion chamber. A vortex combustor was designed in which the oxidiser injected tangentially at the aft end near the nozzle spiraled up to the top plate and formed an inner core inside the chamber. The fuel was injected radially from injectors provided near the top plate and the propellants were mixed in the inner core. This resulted in enhanced mixing and increased residence time for the fuel. More information on the flow behaviour has been obtained by numerical analysis in Fluent. The test also investigated the sensitivity of the tangential injection pressure on the chamber pressure development. Results: All the test cases showed an increase in chamber pressure with the mixture ratio and injection pressure of the propellants. The maximum chamber pressure was found to be 3.8 bar at PC1 and 2.7 bar at PC2 when oxidiser to fuel ratio was 6.87. There was a reduction in chamber pressure of 1.1 bar and 0.7 bar at PC1 and PC2, respectively, in both the cases when hydrogen was injected. A small variation in the pressure of the propellant injected tangentially made a pronounced effect on the chamber pressure and hence vortex combustion chamber was found to be very sensitive to the tangential injection pressure. Conclusion: VCCW mechanism has been to be found to be very effective for keeping the chamber surface within the permissible limit and also reducing the payload of the space vehicle.

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Design and Testing of a Paraffin-Based 1000 N HRE Breadboard

Aerospace ◽

10.3390/aerospace6080089 ◽

2019 ◽

Vol 6 (8) ◽

pp. 89 ◽

Cited By ~ 1

Author(s):

Francesco Battista ◽

Daniele Cardillo ◽

Manrico Fragiacomo ◽

Giuseppe Daniele Di Martino ◽

Stefano Mungiguerra ◽

...

Keyword(s):

Combustion Chamber ◽

Operating Conditions ◽

Research Centre ◽

Chamber Pressure ◽

Hybrid Rocket ◽

Gaseous Oxygen ◽

Mixture Ratio ◽

Rocket Propulsion ◽

Scale Parameters ◽

Firing Test

The paper presents some relevant achievements in hybrid rocket propulsion carried out by the Italian Aerospace Research Centre. On the basis of the experimental results obtained on a 200 N thrust class engine, a 1000 N class breadboard, fed with gaseous oxygen coupled with a paraffin-based fuel grain, was designed and experimentally tested in different conditions. The breadboard exhibited a stable combustion in all the firing test conditions; the testing campaign allowed the acquisition of different experimental data, as pre and post-combustion chamber pressure, throat material temperature, pre-combustion chamber temperature. The new breadboard was characterized by higher measured regression rate values with respect to corresponding data obtained with the smaller scale one, highlighting that the oxidizer mass flux is not the only operating quantity affecting the fuel consumption behavior, which could be also influenced by scale parameters, such as the grain port diameter, and other operating conditions, such as the mixture ratio.

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Influence of Polyisobutylene Kerosene Additive on Combustion Efficiency in a Liquid Propellant Rocket Engine

Aerospace ◽

10.3390/aerospace6120129 ◽

2019 ◽

Vol 6 (12) ◽

pp. 129 ◽

Cited By ~ 1

Author(s):

Igor Borovik ◽

Evgeniy Strokach ◽

Alexander Kozlov ◽

Valeriy Gaponov ◽

Vladimir Chvanov ◽

...

Keyword(s):

Combustion Chamber ◽

Film Cooling ◽

Rocket Engine ◽

Combustion Efficiency ◽

Liquid Propellant ◽

Gaseous Oxygen ◽

Wall Film ◽

Measurement Results ◽

Liquid Propellant Rocket Engine ◽

Propellant Rocket

The combustion of kerosene with the polymer additive polyisobutylene (PIB) was experimentally investigated. The aim of the study was to measure the effect of PIB kerosene on the efficiency of combustion chamber cooling and the combustion efficiency of the liquid propellant for a rocket engine operating on kerosene and gaseous oxygen (GOX). The study was conducted on an experimental rocket engine using kerosene wall film cooling in the combustion chamber. Fire tests showed that the addition of polyisobutylene to kerosene had no significant effect on the combustion efficiency. However, analysis of the wall temperature measurement results showed that the use of PIB kerosene is more effective for film cooling than pure kerosene, which can increase the efficiency of combustion chamber cooling and subsequently increase its reliability and reusability. Thus, the findings of this study are expected to be of use in further investigations of wall film cooling efficiency.

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Life extending controller design for reusable rocket engines

The Aeronautical Journal ◽

10.1017/s0001924000012197 ◽

2001 ◽

Vol 105 (1048) ◽

pp. 315-322 ◽

Cited By ~ 1

Author(s):

A. Ray ◽

M. S. Holmes ◽

C. F. Lorenzo

Keyword(s):

Controller Design ◽

Space Shuttle ◽

Rocket Engine ◽

Design Procedure ◽

Fuel Mixture ◽

Significant Loss ◽

Chamber Pressure ◽

Control Synthesis ◽

Rocket Engines ◽

Mixture Ratio

Abstract The goal of life extending control (LEC) is to enhance structural durability of complex mechanical systems, such as aircraft, spacecraft, and energy conversion devices, without incurring any significant loss of performance. This paper presents a concept of robust life-extending controller design for reusable rocket engines, similar to the Space Shuttle Main Engine (SSME), via damage mitigation in both fuel and oxidiser turbines while achieving the required performance for transient responses of the main combustion chamber pressure and the oxidant/fuel mixture ratio. The design procedure makes use of a combination of linear robust control synthesis and nonlinear optimisation techniques. Results of simulation experiments on the model of a reusable rocket engine are presented to this effect.

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Conceptual Regenerative Nozzle Cooling Design for a Hydroxyl-Terminated Polybutadiene and Oxygen Hybrid Rocket Engine

Volume 4: 22nd Design for Manufacturing and the Life Cycle Conference; 11th International Conference on Micro- and Nanosystems ◽

10.1115/detc2017-68396 ◽

2017 ◽

Author(s):

Luis R. Robles ◽

Johnny Ho ◽

Bao Nguyen ◽

Geoffrey Wagner ◽

Jeremy Surmi ◽

...

Keyword(s):

Combustion Chamber ◽

High Temperatures ◽

Cooling System ◽

Rocket Engine ◽

Combustion Efficiency ◽

Rocket Engines ◽

Hybrid Rocket ◽

Gaseous Oxygen ◽

Rocket Nozzle ◽

Regenerative Cycle

Regenerative rocket nozzle cooling technology is well developed for liquid fueled rocket engines, but the technology has yet to be widely applied to hybrid rockets. Liquid engines use fuel as coolant, and while the oxidizers typically used in hybrids are not as efficient at conducting heat, the increased renewability of a rocket using regenerative cycle should still make the technology attractive. Due to the high temperatures that permeate throughout a rocket nozzle, most nozzles are predisposed to ablation, supporting the need to implement a nozzle cooling system. This paper presents a proof-of-concept regenerative cooling system for a hybrid engine which uses hydroxyl-terminated polybutadiene (HTPB) as its solid fuel and gaseous oxygen (O2) as its oxidizer, whereby a portion of gaseous oxygen is injected directly into the combustion chamber and another portion is routed up through grooves on the exterior of a copper-chromium nozzle and, afterwards, injected into the combustion chamber. Using O2 as a coolant will significantly lower the temperature of the nozzle which will prevent ablation due to the high temperatures produced by the exhaust. Additional advantages are an increase in combustion efficiency due to the heated O2 being used for combustion and an increased overall efficiency from the regenerative cycle. A computational model is presented, and several experiments are performed using computational fluid dynamics (CFD).

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A Study on the Performance and Emissions Characteristics of a DI Compression Ignition Engine Operated With LPG and DTBP Blending Fuels

ASME 2011 Internal Combustion Engine Division Fall Technical Conference ◽

10.1115/icef2011-60214 ◽

2011 ◽

Author(s):

Hoin Kang ◽

Jerald A. Caton ◽

Seangwock Lee ◽

Seokhwan Lee ◽

Seungmook Oh

Keyword(s):

Combustion Chamber ◽

Fuel Injection ◽

Ambient Pressure ◽

Injection Pressure ◽

Chamber Pressure ◽

Injection Timing ◽

Compression Ignition ◽

Compression Ignition Engine ◽

Bench Tests ◽

Fuel Injection Pressure

LPG (Liquefied Petroleum Gas) has been widely used as an alternative fuel for gasoline and diesel vehicles in light of clean fuel and diversity of energy resources. But conventional LPG vehicles using carburetors or MPI fuel injection systems can’t satisfy the emissions regulations and CO2 targets of the future. Therefore, it is essential to develop LPG engines of spark ignition or compression ignition type such that LPG fuel is directly injected into the combustion chamber under high pressure. A compression ignition engine using LPG is the ideal engine with many advantages of fuel economy, heat efficiency and low CO2, even though it is difficult to develop due to the unique properties of LPG. This paper reports on numerical and experimental studies related to LPG fuel for a compression ignition engine. The numerical analysis is conducted to study the combustion chamber shape with CATIA and to analyze the spray and fluid behaviors with FLUENT for diesel and LPG (n-butane 100%) fuels. In one experimental study, a constant volume chamber is used to observe the spray formation for the chamber pressure 0 to 3MPa and to analyze the flame process, P-V diagram, heat release rate and emissions through the combustion of LPG fuel with the cetane additive DTBP (Di-tert-butyl peroxide) 5 to 15 wt% at 25MPa of fuel injection pressure. In engine bench tests, experiments were performed to find the optimum injection timing, lambda, COV and emissions for the LPG fuel with the cetane additive DTBP 5 to 15 wt% at 25MPa fuel injection pressure and 1500 rpm. The penetration distance of LPG (n-butane 100%) was shorter than that of diesel fuel and LPG was sensitive to the chamber pressure. The ignition delay was in inverse proportion to the ambient pressure linearly. In the engine bench tests, the optimum injection timing of the test engine to the LPG fuel with DTBP 15 wt% was about BTDC 12° CA at all loads and 1500 rpm. An increasing of DTBP blending ratio caused the promotion of flame and fast burn and this lead to reduce HC and CO emissions, on the other hand, to increase NOx and CO2 emissions.

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Test Results of a Model Additively Manufactured Oxygen-Methane Combustion Chamber of a Liquid Rocket Engine

Herald of the Bauman Moscow State Technical University Series Mechanical Engineering ◽

10.18698/0236-3941-2021-3-60-79 ◽

2021 ◽

pp. 60-79

Author(s):

S.V. Mosolov ◽

I.G. Lozino-Lozinskaya ◽

D.M. Pozvonkov ◽

D.F. Slesarev

Keyword(s):

Combustion Chamber ◽

Fire Test ◽

Rocket Engine ◽

Methane Combustion ◽

Chamber Pressure ◽

Experimental Unit ◽

Liquid Rocket Engine ◽

Test Results ◽

Test Conditions ◽

Liquid Rocket

The paper focuses on an experimental unit developed for modeling combustion characteristics in a model oxygen-methane combustion chamber of a liquid rocket engine. The key components of the unit, i.e., the mixing head of the combustion chamber and the regeneratively cooled nozzle, were manufactured using advanced methods of additive manufacturing. The paper emphasizes the specific character of the combustion chamber components made with the use of additive technology and introduces hot-fire test results of the model combustion chamber as part of the experimental unit. The study shows the durability of the mixing head and combustion chamber nozzle under hot-fire test conditions, as well as the reliable operation of the experimental unit as a whole, which confirms the selected design and technological solutions. Within the study, we analyzed the cooling system of the experimental unit for the test conditions, estimated the thermal state of the nozzle, with account for the features of the additively manufactured cooling path. To increase the cooling system’s reliability and expand the combustion chamber pressure application, it is recommended to apply a heat-shielding coating on the firewall of the nozzle. Using new experimental data, we analyzed the parameters of improving the efficiency of the model combustion chamber with the additively manufactured components and corresponding in scale and consumption characteristics to the combustion chamber of the liquid rocket engine

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Vortex Combustion Chamber Development For Future Liquid Rocket Engine Applications

38th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit ◽

10.2514/6.2002-4149 ◽

2002 ◽

Cited By ~ 23

Author(s):

Martin Chiaverini ◽

Matthew Malecki ◽

J Sauer ◽

William Knuth ◽

Christopher Hall

Keyword(s):

Combustion Chamber ◽

Rocket Engine ◽

Liquid Rocket Engine ◽

Liquid Rocket ◽

Vortex Combustion

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The Sampling of Rocket Combustion Gases

Journal of the Royal Aeronautical Society ◽

10.1017/s0368393100080883 ◽

1964 ◽

Vol 68 (647) ◽

pp. 759-764

Author(s):

R. Bryan

Keyword(s):

Combustion Chamber ◽

Rocket Engine ◽

Operating Conditions ◽

Combustion System ◽

Combustion Chambers ◽

Ratio Distribution ◽

Mixture Ratio ◽

Combustion Gases ◽

Engine Combustion ◽

Combustion Phase

Summary:—In the past, attempts have been made to evaluate injectors for rocket engine combustion chambers by the use of water analogy rigs and model combustion systems that simulated the injection and combustion phase change occurring in the actual engine. To confirm that conditions in the engine were being correctly simulated, a technique was evolved for determining the mixture ratio distribution achieved by the combustion system of a Spectre variable thrust rocket engine. Gas samples extracted from the rocket-efflux were analysed, and the technique has been applied to evaluate the Spectre's standard central mushroom type injector and also a multi-head injector.Tests have been conducted over a thrust range of 2000 lb to 8000 lb and at oxidant/fuel ratios from 7·5 to 13·0.In parallel with this external sampling, a probe has been designed and developed for extracting gas samples from selected points across a diameter of the combustion chamber itself. This probe has been successfully operated for several minutes under combustion conditions of 500 p.s.i.a. and 2600°K, without sustaining any damage.Analysis of the oxidant/fuel ratio pattern within the combustion chamber and in the efflux, at comparable operating conditions, indicates that little change in distribution occurs between these two points of the system. Also, the distribution found with the standard injector was that for which the combustion system was designed. It is demonstrated that loss of performance depends on the degree of non-uniformity of mixing. A 5 per cent loss in performance at full thrust and optimum mixture ratio occurs with the standard injector.

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Enviromental Pattern Analysis of Biodiesel (Castor, Coconut, MGB) to Support Alternative Energy using CFD approach

Global Journal of Engineering and Technology Advances ◽

10.30574/gjeta.2021.8.1.0100 ◽

2021 ◽

Vol 8 (1) ◽

pp. 051-060

Author(s):

Sutrisno ◽

Avando Bastari ◽

Okol Sri Suharyo

Keyword(s):

Combustion Chamber ◽

Alternative Energy ◽

Injection Pressure ◽

Chamber Pressure ◽

Biodiesel Fuel ◽

Spray Pattern ◽

Cooking Oil ◽

Used Cooking Oil ◽

Mexican Hat ◽

Crown Shape

The Ship uses the MTU 16V956 TB 92 propulsion engine with a piston-type Mexican Hat combustion chamber. In general, the crown is used on machines with large torque. Besides that, the crown shape in the combustion chamber is also very influential on the formation of a mixture of fuel and air before the combustion process occurs. So it is necessary to know about the spray pattern of biodiesel fuel of enviromental things (castor, coconut, used cooking oil/MGB) in the Mexican Hat combustion chamber. In this study, using the Mexican Hat-shaped piston crown simulation method, the first step was to test the spray pattern of the three types of biodiesel (castor, coconut, used cooking oil) by simulating a tube with an injection pressure of 350 bar gauge pressure inside a barometric pressure tube. While the completion in the Mexican Hat combustion chamber with a chamber pressure of 35 bar gauge and injection pressure of 350 bar gauge was completed with the CFD program, Fluent 6.2, and the results of the three biodiesels were compared. From the CFD simulation results obtained spray patterns of the three types of biodiesel (castor, coconut, used cooking oil). At the same injection pressure and chamber pressure, used cooking biodiesel has the longest penetration length, followed by castor biodiesel and coconut biodiesel. The spray angle of coconut biodiesel is the largest, followed by castor biodiesel and used cooking oil biodiesel. SMD coconut biodiesel is the smallest, followed by castor biodiesel and used cooking oil biodiesel.

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