Orographic Shading Effect on Water/Sediment Heat Exchange in Two Dams of Guanajuato River, Mexico

详细信息    查看全文

• 作者：Jofre-Melé ; ndez Rodolfo^a ; ^{rod_jm25@hotmail.com} ; Ramos-Arroyo Yann^a ; Botello-Rionda Salvador^b
• 关键词：Orographic shading ; heat exchange ; sediments
• 刊名：Procedia Earth and Planetary Science
• 出版年：2017
• 出版时间：2017
• 年：2017
• 卷：17
• 期：Complete
• 页码：873-876
• 全文大小：1055 K
• 卷排序：17

文摘

Heat fluxes in dams affect the concentrations of dissolved oxygen and the liberation of potentially toxic elements (Fe, Mn, As and sulfides) from sediments. Sediments/water column heat exchange in dams traditionally is neglected by numerical models because it represents a few percent of heat exchange processes; however these exchanges become important in small reservoirs located at hilly areas. The present work attempts to focus on the importance of orographic shading in small dams (<1 Mm3). Two dams, Esperanza and Santana, located at Guanajuato river basin, Mexico, between two physiographic provinces with very irregular relief were investigated. Hydrodynamic model for reservoirs, CE-QUAL-W2, was used to detect orographic shading effects in dams studied. A heat diffusive model was developed with finite element method to calculate atmosphere/water surface and sediment/water column heat fluxes. Results show that the percent of sediment/water column heat flux is 85% for Esperanza dam and 96% for Santana dam, while heat fluxes in atmosphere/water surface interface were of 15% and 4% for Esperanza and Santana dams, respectively. With this, the importance of heat fluxes in this interface are revealed, also the increase of these flows in relation to bigger dams in lower relief zones was quantified.