Date of Award

12-1991

Document Type

Thesis

Degree Name

Master of Science

Department

Department of Aeronautics and Astronautics

First Advisor

Philip S. Beran, PhD

Abstract

The AFIT Total Variation Diminishing Euler Code (ATEC) was modified to include a thermal nonequilibrium model to investigate high temperature effects associated with vibrational relaxation in a transonic turbine cascade. Incorporation of this model into ATEC and creating ANTEC (AFIT Nonequilibrium TVD Euler Code) was accomplished in three steps. Steady-state solutions obtained with ANTEC were compared with those obtained with ATEC for various inlet and exit conditions. The Courant-Friedrichs-Levy criterion was held constant to ATEC; however, it required variation for ANTEC. Blade temperature profiles, temperature difference contours in the vicinity of the trailing edge and the value of the ratio of specific heats (๐›พ) along the blade were analyzed. Even when corrected for high temperatures, the assumptions of a calorically perfect gas and thus a constant value of ๐›พ are inaccurate due to the temperature dependent nature of specific heats at constant pressure and at constant value. Maximum temperature differences of -741 K and 539 K were found near the trailing edge for the highest temperature case, with differences being most noticeable through the expansion at the trailing edge on the pressure surface and across the shocks from both surfaces. The vibrational relaxation model showed limitations at low temperatures.

AFIT Designator

AFIT-GAE-ENY-91D-25

DTIC Accession Number

ADA244049

Comments

The author's Vita page is omitted.

Additional Files
shaw_298.pdf (115 kB)
SF298 for AFIT-GAE-ENY-91D-25
Download

Share

COinS