@techreport{oai:jaxa.repo.nii.ac.jp:00045385,
 author = {KUMAKAWA, Akinaga and SASAKI, Masaki and SATO, Kazuo and ONO, Fumiei and SAKAMOTO, Hiroshi and YATSUYANAGI, Nobuyuki},
 month = {Oct},
 note = {ロケット燃焼器の熱負荷低減及び長寿命化を目的として燃焼器を2台試作し、液酸/ガス水素、液酸/ガスメタンおよび液酸/RJ-1Jを推進剤とする水冷却高圧燃焼試験に供した。試験は最大燃焼圧力12MPa、最大熱流束120MW/m2の範囲で実施した。液酸/ガス水素、液酸/ガスメタンの燃焼試験において、熱負荷はニッケル層無しに比べて約20～30％低下し、ニッケル層の遮熱性の有効性が示された。このニッケル層の熱抵抗は計算値よりもはるかに大きい値であった。試験後の断面観察からニッケル層の厚さ方向には巨視的な破壊には到らないマイクロクラックが多数生じており、これが熱抵抗増加の主因子と考えられた。ニッケル層の熱抵抗は厚さが異なるにも係わらず、燃焼静圧と良い相関性を示し、燃焼静圧の増加とともに減少したところから、この推定が正しいことを裏付けた。液酸/RJ-1Jの燃焼試験では、カーボン層の堆積特性に壁材質あるいは壁温の相違、水素添加の有無及び噴射器エレメント形式の相違が大きく影響することがわかった。また、同一燃焼圧力、混合比の条件下では、カーボン層が堆積した場合の熱流束の値は、堆積がない場合の約50％の値まで低下することがわかった。各ニッケル層は約30回、累積燃焼時間600秒の燃焼試験に供されたが,脱落、剥離等は観察されず,その耐久性及び遮熱性の有効性が示された。, The chamber walls of two water-cooled calorimetric combustors of different chamber length were electroplated with nickel of diffenrent thickness to investigate decreasing the temperature of the substrate copper wall and prolonging thrust chambers life. Combustion tests were conducted using liquid oxygen (LOX)/gaseous hydrogen, LOX/gaseous methane, and LOX/RJ-1J propellants. The maximum chamber pressure was 12 Mpa and the maximum heat flux reached 120 MW/m2. For both the LOX/hydrogen and LOX/methane propellants, heat flux values measured at the throat section of the nickel plated chambers were 20-30％ less than those measured for the bare copper chamber walls. This infers that subcritical microcracks observed within the nickel layer functioned to relax the layer′s thermal stress and to cause a higher thermal resistance than expected. On the other hand, the test results of the LOX/RJ1-J propellant showed that the wall material and/or temperature, the presence of hydrogen, and the injection pattern of propellants all affected the characteristics of carbon deposition on the chamber wall. It was also experimentally revealed that at the same mixture ratio the heat flux values in the presence of carbon deposition were lowered by 50％ compared to those in the absence of carbon deposition. Both nickel layers survived approximately 30 firing tests having a total duration of 600 s. The durability and reliability of the nickel plating were verified, there by showing that a thin layer of nickel plating is useful for decreasing the heat load of high pressure thrust chambers., 資料番号: NALTR1126000, レポート番号: NAL TR-1126T},
 title = {Characteristics of Heat Transfer to Nickel Plated Chamber Walls of High Pressure Rocket Combustors},
 year = {1991}
}