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Title: A mechanism of wave drag reduction in the thermal energy deposition experiments

Abstract

Many experimental studies report reduced wave drag when thermal energy is deposited in the supersonic flow upstream of a body. Though a large amount of research on this topic has been accumulated, the exact mechanism of the drag reduction is still unknown. This paper is to fill the gap in the understanding connecting multiple stages of the observed phenomena with a single mechanism. The proposed model provides an insight on the origin of the chain of subsequent transformations in the flow leading to the reduction in wave drag, such as typical deformations of the front, changes in the gas pressure and density in front of the body, the odd shapes of the deflection signals, and the shock wave extinction in the plasma area. The results of numerical simulation based on the model are presented for three types of plasma parameter distribution. The spherical and cylindrical geometry has been used to match the data with the experimental observations. The results demonstrate full ability of the model to exactly explain all the features observed in the drag reduction experiments. Analytical expressions used in the model allow separating out a number of adjustment parameters that can be used to optimize thermal energy inputmore » and thus achieve fundamentally lower drag values than that of conventional approaches.« less

Authors:
 [1]
  1. Physics Department, Old Dominion University, Norfolk, Virginia 23529 (United States)
Publication Date:
OSTI Identifier:
22490952
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COMPUTERIZED SIMULATION; CYLINDRICAL CONFIGURATION; DRAG; ENERGY ABSORPTION; PLASMA; SHOCK WAVES; SIGNALS; SPHERICAL CONFIGURATION; SUPERSONIC FLOW; TRANSFORMATIONS

Citation Formats

Markhotok, A., E-mail: amarhotk@phys.washington.edu. A mechanism of wave drag reduction in the thermal energy deposition experiments. United States: N. p., 2015. Web. doi:10.1063/1.4922434.
Markhotok, A., E-mail: amarhotk@phys.washington.edu. A mechanism of wave drag reduction in the thermal energy deposition experiments. United States. doi:10.1063/1.4922434.
Markhotok, A., E-mail: amarhotk@phys.washington.edu. Mon . "A mechanism of wave drag reduction in the thermal energy deposition experiments". United States. doi:10.1063/1.4922434.
@article{osti_22490952,
title = {A mechanism of wave drag reduction in the thermal energy deposition experiments},
author = {Markhotok, A., E-mail: amarhotk@phys.washington.edu},
abstractNote = {Many experimental studies report reduced wave drag when thermal energy is deposited in the supersonic flow upstream of a body. Though a large amount of research on this topic has been accumulated, the exact mechanism of the drag reduction is still unknown. This paper is to fill the gap in the understanding connecting multiple stages of the observed phenomena with a single mechanism. The proposed model provides an insight on the origin of the chain of subsequent transformations in the flow leading to the reduction in wave drag, such as typical deformations of the front, changes in the gas pressure and density in front of the body, the odd shapes of the deflection signals, and the shock wave extinction in the plasma area. The results of numerical simulation based on the model are presented for three types of plasma parameter distribution. The spherical and cylindrical geometry has been used to match the data with the experimental observations. The results demonstrate full ability of the model to exactly explain all the features observed in the drag reduction experiments. Analytical expressions used in the model allow separating out a number of adjustment parameters that can be used to optimize thermal energy input and thus achieve fundamentally lower drag values than that of conventional approaches.},
doi = {10.1063/1.4922434},
journal = {Physics of Plasmas},
number = 6,
volume = 22,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}
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