Modelowanie numeryczne i pomiary termograficzne parametrów procesu hamowania

• Autorzy: Piątkowski T. , Polakowski H. , Małachowski J. , Damaziak K.

Warianty tytułu

EN

Numerical modeling and thermographics measurements of break phenomena parameters

• Języki publikacji: PL

Abstrakty

PL

W pracy przedstawiono wybrane wyniki dotyczące modelowania numerycznego oraz badań termograficznych hamulców tarczowych. Do określenia w czasie rozkładu temperatur na powierzchni klocków hamulcowych wykorzystano metodę elementów skończonych. Wykonano też pomiary termograficzne zarówno tarczy hamulcowej jak i okładzin ciernych. Wykonano pomiary temperatur pary trącej zarówno w czasie procesu hamowania jak również chłodzenia hamulca. Określono rozkład temperatur w wybranych przekrojach par ciernych badanych na stanowisku pomiarowym.

EN

Considerable amount of heat is generated in a limited volume of the brake during vehicle braking, which results in several undesired effects, such as thermal shock, local overheating of brake elements and cooling problems. In this paper, selected results of thermal measurements of the braking process are presented, performed on the IL-68 test stand (Fig. 1.) The numerical model of this stand was also created (Fig. 2, Fig. 3) and the numerical simulations of the first 100 ms of the braking process was performed. The temperature distribution across the surface of brake pads was calculated (Fig. 4) as well as the maximal temperature values throughout simulated period. Temperature distribution in the test brake was also measured, using thermal imaging (Fig. 5). Because of the measurement range of the applied thermal camera the measurements were started 300 ms after the brake was engaged and the next 2,5 s were recorded at 1000 frames per second. Sample image from the beginning of the recorded sequence is presented in Fig.6a, whereas Fig.6b shows the breaking disc when it was stopped. The temperature changes versus time presented in Fig. 7 were obtained on the basis of frame-by-frame analysis and their character is in accordance with previously calculated, simulated values. The cooling process of the entire brake thermal node was also investigated, which is very important as after several consecutive braking cycles the heat accumulates. The temperature changes after braking depicted in Fig. 8indicate rather low cooling rate. Thermal time constants (1), (2) of thisprocess were determined. The data gathered during the analysis of thermal images will be used to verify the numerical model of the brake and will also be used as design guidelines in the optimization of brake design for improved heat transfer.

Słowa kluczowe

PL

modelowanie numeryczne; tarcie; parametry cieplne; termowizja; pomiary temperatury

EN

numerical modelling; friction; thermal parameter; thermography; temperature measurements

• Wydawca: Wydawnictwo PAK
• Czasopismo: Pomiary Automatyka Kontrola
• Rocznik: 2011
• Tom: R. 57, nr 10
• Strony: 1210--1213
• Opis fizyczny: Bibliogr. 10 poz., rys., wykr., wzo

Twórcy

autor

Piątkowski T.

autor

Polakowski H.

autor

Małachowski J.

autor

Damaziak K.

• Wojskowa Akademia Techniczna, Instytut Optoelektroniki, Wydział Mechaniczny,ul. Gen. Sylwestra Kaliskiego 2, 00-908 Warszawa,

Bibliografia

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