SK1652023A3

SK1652023A3 - Engine cooling system with propeller

Info

Publication number: SK1652023A3
Application number: SK165-2023A
Authority: SK
Inventors: Ondrej Mitter; Karol Szpara; Ing. Gašparovič Peter, PhD.
Original assignee: Ondrej Mitter; Karol Szpara; Ing. Gašparovič Peter, PhD.
Priority date: 2021-04-14
Filing date: 2021-04-14
Publication date: 2024-02-14

Abstract

Cooling device formed by the side walls (5) in front of the inlet opening (6) and at the back of the outlet opening (7), while the flow cross-sectional area between the inlet opening (6) and the cooler (4) gradually increases, and also increases between the cooler (4) ) and outlet hole (7). The cooling system is located in front of the thrust propeller of the aircraft engine. The cooling system is advantageous for improving the cooling efficiency of the aircraft engine when moving on the ground.

Description

Oblasť technikyThe field of technology

Vynález sa týka usporiadania chladiča lietadla s tlačnou vrtuľou, konkrétne usporiadania chladiaceho ústrojenstva, ktoré slúži pre prívod a odvod chladiaceho vzduchu od chladiča.The invention relates to the arrangement of an aircraft cooler with a thrust propeller, specifically to the arrangement of a cooling system that serves for the supply and removal of cooling air from the cooler.

Doterajší stav technikyCurrent state of the art

Chladenie motorov s vnútorným spaľovaním, ktoré sú používané na pohon lietadiel s vrtuľovou pohonnou jednotkou využíva vzduch okolia, ktorý má nižšiu teplotu, ako motor. Tepelná energia sa odvádza z motora na okolitý vzduch buď pomocou chladiacich rebier na povrchu motora (takzvané vzduchové chladenie), alebo prostredníctvom chladiacej kvapaliny, ktorá cirkuluje medzi telesom motora a externým chladičom, na ktorom sa tepelná energia odvádza z kvapaliny na okolitý vzduch (takzvané kvapalné chladenie). Kvapalné chladenie umožňuje dosahovať nižšie teploty telesa motora, ale za cenu väčšej konštrukčnej zložitosti chladenia. Účelom chladiacich rebier vzduchového chladenia a chladiča kvapalného chladenia je poskytnúť dostatočnú plochu, aby sa tok tepelnej energie dial pri dostatočne nízkej teplote chladiaceho povrchu, ktorú znesie motor a jeho kvapaliny. Zníženie teploty pri danom tepelnom toku je mierou účinnosti chladenia. Na účinnosť chladenia majú vplyv okrem veľkosti chladiacich plôch aj teplota okolitého vzduchu, nadmorská výška, a hlavne rýchlosť okolitého vzduchu, ktorou prúdi okolo chladiacich plôch.Cooling of internal combustion engines, which are used to power propeller-driven aircraft, uses ambient air that has a lower temperature than the engine. Thermal energy is dissipated from the engine to the ambient air either by means of cooling fins on the surface of the engine (so-called air cooling) or by means of a cooling liquid that circulates between the engine body and an external radiator, on which the thermal energy is dissipated from the liquid to the ambient air (so-called liquid cooling). Liquid cooling makes it possible to reach lower temperatures of the engine body, but at the cost of greater structural complexity of the cooling. The purpose of the cooling fins of the air cooling and the liquid cooling radiator is to provide enough surface area for the flow of heat energy to occur at a low enough cooling surface temperature that the engine and its fluids can tolerate. The temperature reduction at a given heat flow is a measure of cooling efficiency. In addition to the size of the cooling surfaces, the temperature of the surrounding air, altitude, and especially the speed of the surrounding air flowing around the cooling surfaces have an effect on the cooling efficiency.

Kritickým prípadom pre chladenie motora lietadla je pohyb lietadla po zemi, pretože motor generuje porovnateľné množstvo tepla ako za letu, ale okolitý vzduch sa voči lietadlu pohybuje zanedbateľnou rýchlosťou v porovnaní s rýchlosťou za letu, takže sa zjednodušene predpokladá že vzduch je v relatívnom pokoji voči lietadlu.A critical case for aircraft engine cooling is ground motion, as the engine generates a comparable amount of heat as in flight, but the surrounding air is moving relative to the aircraft at a negligible speed compared to flight speed, so the air is simply assumed to be at relative rest relative to the aircraft .

Chladenie motora, ktoré býva navrhnuté pre podmienky za letu lietadla, má nedostatočnú účinnosť pri pohybe na zemi. Z toho vyplýva časové obmedzenie činnosti motora na zemi, nutnosť sledovania teploty na zemi. Zlepšenie účinnosti chladenia na zemi sa rieši nútenou konvekciou vzduchu pomocou dodatočných ventilátorov, ktoré zvyšujú hmotnosť lietadla a zložitosť chladenia.Engine cooling, which is usually designed for in-flight conditions, has insufficient efficiency when moving on the ground. This results in a time limitation of the engine's operation on the ground, and the necessity of monitoring the temperature on the ground. Improving the efficiency of cooling on the ground is solved by forced convection of air using additional fans, which increase the weight of the aircraft and the complexity of cooling.

Podstata vynálezuThe essence of the invention

Podstatou vynálezu je zlepšenie účinnosti chladenia motora lietadla pri nízkych rýchlostiach počas pohybu lietadla na zemi bez použitia dodatočných ventilátorov. Podstatou vynálezu je využitie sacieho účinku vrtule pri tlačnom usporiadaní pohonu, a tvarovanie chladiaceho ústrojenstva tak, aby umožňovalo optimálny prietok chladiaceho vzduchu chladičom za letu aj pri pohybe na zemi. Sanie vrtule vytvorí v mieste chladiča prúdenie vzduchu, ktorého rýchlosť sa blíži rýchlosti prúdenia vzduchu za letu. Situácia pri pohybe lietadla na zemi je znázornená na obrázku 1. Prúdenie vzduchu v smere čiarkovaných šípok je v mieste chladiča ešte urýchlené chladiacim ústrojenstvom, ktoré je tvorené kanálom, ktorého vstupný otvor má menší plošný obsah ako čelná plocha chladiča, a tá je zasa menšia ako výstupný otvor chladiaceho ústrojenstva.The essence of the invention is to improve the cooling efficiency of the aircraft engine at low speeds during the movement of the aircraft on the ground without the use of additional fans. The essence of the invention is the use of the suction effect of the propeller in the thrust arrangement of the drive, and the shaping of the cooling system in such a way as to allow an optimal flow of cooling air through the cooler in flight and when moving on the ground. The suction of the propeller creates a flow of air at the place of the radiator, the speed of which is close to the speed of air flow in flight. The situation during the movement of the aircraft on the ground is shown in Figure 1. The air flow in the direction of the dashed arrows is further accelerated at the place of the cooler by the cooling system, which is formed by a channel, the inlet opening of which has a smaller surface area than the frontal surface of the cooler, which in turn is smaller than outlet opening of the cooling system.

Za letu, naopak, chladiace ústrojenstvo spomaľuje prúdenie vzduchu tak, aby nedochádzalo k podchladeniu motora, a aby sa znížil aerodynamický odpor chladiča. To sa dosahuje tým istým tvarom chladiaceho ústrojenstva, kedy v smere prúdenia, od vstupného otvora ku chladiču sa plocha prietočného prierezu zväčšuje. Oproti doterajším chladiacim ústrojenstvám sa však plocha prietočného prierezu za chladičom ďalej zväčšuje, čo je dôležité práve pri práci na zemi.In flight, on the contrary, the cooling system slows down the air flow so that the engine does not undercool and to reduce the aerodynamic resistance of the radiator. This is achieved by the same shape of the cooling device, when in the flow direction, from the inlet opening to the cooler, the cross-sectional area of the flow increases. Compared to existing cooling devices, however, the cross-sectional flow area behind the cooler continues to increase, which is especially important when working on the ground.

Prehľad obrázkov na výkresochOverview of images on drawings

Obrázok 1 obsahuje znázornenie konfigurácie chladiaceho ústrojenstva lietadla a schému prúdenia vyvolanú vrtuľou pri práci na zemi.Figure 1 contains an illustration of the aircraft cooling configuration and the propeller-induced flow diagram when operating on the ground.

Príklady uskutočnenia vynálezuExamples of implementation of the invention

Na obrázku 1 je znázornená konfigurácia chladiaceho ústrojenstva. V zadnej časti trupu 1 lietadla je tlačná vrtuľa 2, ktorá pri pohybe lietadla po zemi vytvára prúdenie vzduchu v okolí lietadla a teda aj v mieste chladiča 4, pričom smer tohto prúdenia je naznačený čiarkovanými šípkami 3.Figure 1 shows the configuration of the cooling system. In the rear part of the fuselage 1 of the aircraft, there is a thrust propeller 2, which, when the aircraft moves on the ground, creates an air flow around the aircraft and thus also in the place of the radiator 4, while the direction of this flow is indicated by dashed arrows 3.

SK 165-2023 A3SK 165-2023 A3

Chladič 4 je umiestnený pred tlačnou vrtuľou 2, vo vzdialenosti približne jeden polomer vrtule pred rovinou otáčania vrtule. Zároveň je chladič umiestnený v kanáli, ktorý je tvorený bočnými stenami 5 chladiaceho ústrojenstva, spredu vstupným otvorom 6, a vzadu výstupným otvorom 7. Plocha prietočného prierezu medzi vstupným otvorom 6 a chladičom 4 sa postupne zväčšuje, a rovnako sa zväčšuje aj medzi 5 chladičom 4 a výstupným otvorom 7.The cooler 4 is located in front of the thrust propeller 2, at a distance of approximately one radius of the propeller in front of the plane of rotation of the propeller. At the same time, the cooler is placed in the channel, which is formed by the side walls 5 of the cooling device, the inlet opening 6 at the front, and the outlet opening 7 at the back. The flow cross-sectional area between the inlet opening 6 and the cooler 4 gradually increases, and it also increases between 5 and the cooler 4 and outlet hole 7.

Priemyselná využiteľnosťIndustrial applicability

Chladiace ústrojenstvo je využiteľné pre chladenie motorov lietadiel s tlačnou vrtuľou.The cooling system can be used for cooling the engines of airplanes with a push propeller.

Claims

PATENT CLAIMS

1. Cooling device, characterized in that the channel formed by the side walls (5), in which the cooler (4) is located, expands not only in the front part, from the inlet opening (6) in the direction 5 of the air flow, but also in the rear part , towards the outlet opening (7), while this cooling device is located in front of the thrust propeller (2).

2. Cooling device according to claim 1, characterized in that the outlet opening (7) is located at a distance of approximately the radius of the propeller (2) in front of the plane of rotation of the propeller (2).

3. A cooling device according to claim 1, characterized in that the ratio of the area content of the outlet opening (7) and the front surface of the cooler (4) is between 1.5 and 2.